# Air sealing satisfaction.



## TradEddie (Jan 23, 2013)

I've been doing on-going air-sealing around my house as time allows for more than a year, with limited measurable success, but tonight, with 10F outside to help locate problem areas, I hit some electrical outlets in the bedrooms.  The first I could get through a crawlspace, and the fiberglass all around the box was totally discolored from filtering the exiting air. The second was only accessible from the front, but the receptacle box was completely filled with dust.

I have often wondered if I'm achieving anything with this, but tonight I saw for the first time unequivocal evidence of the quantity of air I'm losing through leaks like these. Hopefully eventually I'll be able to see the benefits in my heating bills too.

TE


----------



## midwestcoast (Jan 24, 2013)

Nice to get some satisfaction out of a tedious job.  Every little bit helps.
Maybe you've already hit these, but the big game for air sealing is usually found high and low. Attic and basement. This is where air pressure is driving air out (attic) and in (basement). Not as noticeable as in the living space, but there can be lots of air moving out of sight.
Attic hatch, chimney, plumbing stack, pipe chases, can lights, soffits, cantilevered floors, missing headers, sill plates, utility feeds all can be big leaks.  In my house I had open joist bays running from under my 2'nd story floor straight into a side attic.  Hmmm,   why is this floor always so cold?


----------



## TradEddie (Jan 24, 2013)

I've been hitting all of those areas, a few minutes here and there, as much as two kids any my own other hobbies allow. I just wish I could notice an improvement to show for all that work. Sure, I can see better IR temperatures around the sealed areas, but with last year's mild winter, no noticeable reduction in heating bill. Downstairs receptacles are somewhat satisfying because you can feel the draft entering, but upstairs I was happy to see signs of exfiltration after several nights of sealing receptacles in other rooms.

I'm leaving the attic to last, its a poorly ventilated, cramped cape crawlspace, with 35 years of mice droppings, carpenter ant infestations, mold, exfiltrated dust and general unpleasantness.

TE


----------



## semipro (Jan 24, 2013)

I've been working on sealing up air leaks too and came to the conclusion that I was wasting my time sealing them up from the inside.  If I sealed one hole it only seemed to increase the flow at other areas like interfaces between the chimney and walls. It was obvious much air was making its way into my walls from outside (along with moisture). 
I spent some time researching and it seems that you should create a single air-seal envelop either at the sheathing or the inside walls (e.g. airtight drywall).  In my case it was easier to establish this envelope at the outside (house wrap, foam, tape, caulk).
I think the point is that you need one "good" air barrier and that creating partial ones both inside and outside is not nearly as effective.


----------



## TradEddie (Jan 24, 2013)

semipro said:


> I think the point is that you need one "good" air barrier and that creating partial ones both inside and outside is not nearly as effective.


I have the same suspicion that sealing one leak merely increases the flow through others, partially negating the benefits, but unless I spend thousands of dollars to rip apart my entire exterior, sealing inside is my only option. It costs next to nothing, except for time. Despite its age, my house appears to have insulation upgrades by previous owners, so I'm already in the area of diminishing returns, just trying to correct the glaring errors and problems.

TE


----------



## woodgeek (Jan 24, 2013)

TradEddie said:


> I've been hitting all of those areas, a few minutes here and there, as much as two kids any my own other hobbies allow. I just wish I could notice an improvement to show for all that work. Sure, I can see better IR temperatures around the sealed areas, but with last year's mild winter, no noticeable reduction in heating bill. Downstairs receptacles are somewhat satisfying because you can feel the draft entering, but upstairs I was happy to see signs of exfiltration after several nights of sealing receptacles in other rooms.
> 
> I'm leaving the attic to last, its a poorly ventilated, cramped cape crawlspace, with 35 years of mice droppings, carpenter ant infestations, mold, exfiltrated dust and general unpleasantness.
> 
> TE


 
I spent the last 3 years doing a DIY seal on my attic floor. Overall, I think I am down the equivalent of ~200 gals of oil just from the attic seal (about 20% of original demand). (Also got ~100 gal reduction just from cleaning the metal weatherstrips on my 50 yo windows, putting vinyl vstrips on the horizontals and shimming the locks so all the strips are actually engaged).

So, if the attic work was say 10 rounds in the attic of a couple hours each, after each round I could expect a couple % savings benefit. I could see this sort of gain as I went by (OCD alert) timing my heater cycling (with a stopwatch) and data fitting (a line to duty cycle versus outdoor temp). So, if you are willing to be crazy metering your energy usage, you can get the satisfaction.

OTOH, maybe you haven't hit the big stuff yet. As semi said, a lot of the benefit comes at the end, since air can find other paths. I thought I was done several times, and then discovered leaks (and top plates) that I had missed before. At some stage, looking at snow melting on your roof is VERY handy. If your roof holds snow longer than every other house in the neighborhood, then maybe you can call 'er done. The snow thing is prob the easiest way to confirm that you are getting a benefit.

EDIT: AAh, I see you are saving the attic to last.  I wouldn't.  Its low hanging fruit.  Sealing my (interior wall and gable end) top plates took ~25 tubes of caulk (think ~200' of bead).  So, my advice is get a good gun (power?) and good PP.  I started out with (nice) paper masks, and was clearly still breathing too much chit.  Upgraded to a valved filter respirator and it was much more comfortable and totally protecting.  I just wore old clothes (and changed+showered immediately afterwards) but you could also pick up a tyvek suit if you prefer.  IOW, like a lot of DIY the tool/gear makes the job go a lot easier.

My rim joists are all hidden by drywall in finished space....


----------



## TradEddie (Jan 24, 2013)

I've thought it before, but you may be my long lost twin! I've considered correlating duty cycle with outdoor temperatures, I just can't think of a good cheap way to do it, and I won't sit with a stopwatch. I have all the necessary toys at work, so its frustrating to think about using inferior methods at home. I have been tracking my overnight temperature drop in hopes of seeing improvements.

I'm confused about how sealing top plates helps, or perhaps I don't know exactly what you mean. Can you explain? If I have no unsealed drywall penetrations, how does it help? Is it preventing air flow through the stud bays that cools the walls without actually having a leak to/from conditioned space? The areas of my attic that I know I need to hit are the vent stack and electrical penetrations, but otherwise I don't have much.

TE


----------



## woodgeek (Jan 24, 2013)

Capes can be really difficult. I have a 1960 'side by side' split level. During construction, the house was framed before drywalling, and the attic floor joists sit on 2x4 plates that run at the top of all the interior and exterior walls. The drywallers would leave a small gap between the 2x4 and the sheetrock, to allow expansion. That leaves a 1/16-1/8" gap between the drywall and the plate (on both sides) connecting the attic space to the wall cavities. Multiplied by the perimeter of the house and the length of the interior walls, this little gap adds up to a few square feet of opening (!), easily dwarfing the opening from things like ceiling j-boxes or recessed lights (in my case). How does air get into the drywalled cavity....through the hardwood floor, around the bottom plates (which also have a gap) and other details.

So, I did have to do a plumbing chase and a masonry chimney chase, and sealed a lot of wiring holes (coming up through the top plates), but the major thing for me was ~30' of open stud bays (along the split level) and 200' of top plate cracks.

In capes, IIRC, the kneewall spaces are supposed to be tough....lots of open bays to the second floor joists. To seal cavities, I bought kitchen-sized garbage bags, but a 14" length of FG bat in it, folded it over double and stuffed it in the cavity...the batt holds it in, the bag prevents airflow. PRob not perfect, but easy and fast in a cramped space. In a cape, I might want to call in a pro or get some pro advice about the roof venting.

Recent studies show <1% of air leakage is through electrical boxes in most homes. One earlier study reported 20%, but that was wrong.


----------



## TradEddie (Jan 24, 2013)

I'll look at the top plates whenever I go up there, but I'd sooner pay the propane bill than pull all that FG to airseal inch by inch. My kneewall crawl spaces were/(are?) a mess, when we moved in, the access doors were held in place with magnetic clasps, and there was at least a 1/2" gap on top of each door. Some 1x2s were placed up under the roofline to try open a channel to the main attic.Needless to say, that was a moldy mess in there. The crawlspaces are floored, so no access to seal the bays running under the upstairs rooms. I put down batts on the floor, paper face down, foam spacers to the main attic, and an insulated plywood inner door pulled tight against the frame. Better than nothing but not ideal.

There were so many other disasters I could list, the fireplace is located in a completely uninsulated brick wall to the garage, with wooden mounting brackets for the mantel penetrating that brick wall...

The odd thing is that the house was built in 1977, but had R13 in the walls, which seems good for the time, and presumably sometime after that, R-5 foam and Tyvek was added outside, yet those huge gaps in the access doors were never looked at...

TE


----------



## woodgeek (Jan 24, 2013)

Yup.  Airsealing was really neglected in the 70s and 80s....noone had any idea (in the US anyway).

Depending on your layout and flooring, your situation can be hard to predict.  I remember finding a 'airsealing guide for cape houses' document on the net once, you might google around to see what you can find. There are some common airsealing faults in that layout. I wouldn't worry about top plates much in your case....really a big issue for ranch-ey type houses with big flat attic floors.

i would worry about open stud bays and open joists.  So, if you are in the knee crawl, you are sitting on the joists for the second floor, and there is conditioned space to one side.  If the crawlspace is unconditioned, you have insulation on the vertical wall and the floor.  IF its conditioned, the insulation is on the roofline.  In etiher case, I would worry about those joists running under your second floor.  I would want them to be sealed, so the (second) floor cavity is not connected to the knee crawl.  But I think many builders leave that open, or hope that a FG batt will block airflow.  IF they're open, the 'batt in bag' method is a pretty fast and easy way to plug them.

I would be more worried if the second floor is permeable (i.e. hardwood boards) than impermable (e,g, plywood subfloor and carpet).

Of course, you can get a cheap blower door test done to estimate how much of a problem you have in the first place.


----------



## midwestcoast (Jan 24, 2013)

Yeah, mine's a 1950 built Cape. I didn't seal all my top plates, just the areas where I saw evidence of filtration. Had bigger fish to fry. I also did a lot of reading to figure out how the house was framed & what I could do to tighten it up.
 It was HELL just getting access to my side-attics (space behind the knee walls) since no access was provided.  I have 2 large & 2 small. I cut a hole in a downstairs closet ceiling and hoisted myself up into one and for another I had to crawl down the ceiling of a stairwell, face first, building a ladder as I went, k.  In both cases I found the open bays and no insulation above the ceilings at all. I used the FG folded in a bag to seal the open joist bays, but also put a squirt of Great Stuff along the edges.  The 2 small side attics I couldn't access, so I just drilled some 2" holes and filled those suckers up more than half way with cellulose, then I took off the shoe molding, drilled little holes in the floor & sprayed Great Stuff Big Gap to seal the Joist Bays. It seemed to fill them after 2 to 3 rounds.  Went through a lot of that foam.


----------



## EatenByLimestone (Feb 17, 2013)

I've been taking advantage of the strong wind today and have been sealing up a storm.  I'm beat, but my upstairs is much tighter.  I cheated and am using a plastic window seal over an open hatch to a knee wall.  I'll do the actual sealing of the area behind the knee wall when I can pull all of the junk out of there.

I sealed up some big leaks.  It's sassyfying.

Matt


----------



## GaryGary (Feb 17, 2013)

I've been working on a diy blower door.

Its an old furnace blower mounted on a piece of plywood that is sized to go in a window.  You mount it in the window with the exhaust facing out and plug it in -- makes a lot of breeze.

I've tested it in my shop, and on high speed it can pull more than 50 Pa in my not so well sealed shop.  Plan to try it in the house in the next couple days.

I measure the pressure difference from house to outside with a $10 ebay Dwyer Magnehelic pressure gage that goes 0 to 0.2 inches of water -- so, its basically full scale at 50 Pa.  These gages are really nicely made and seem to always be available on ebay.  Working on a simple way to measure the flow rate so that I can estimate an actual Air Changes per Hour number.

I picked up the blower motor at the local Habitat Restore for $15, but also got one some time back for nothing from a furnace installer.  Most of them have 4 speeds.

I like the idea that I can now take my time finding leaks and actually see the change in pressure drop and flow.

Gary


----------



## semipro (Feb 17, 2013)

I've been looking for a fixer upper fog machine on eBay. I plan in to use it inside the house to locate air leaks. You fill the house with smoke them pressurize it with a small fan then go outside to look for the leaks


----------



## begreen (Feb 18, 2013)

EatenByLimestone said:


> I've been taking advantage of the strong wind today and have been sealing up a storm. I'm beat, but my upstairs is much tighter. I cheated and am using a plastic window seal over an open hatch to a knee wall. I'll do the actual sealing of the area behind the knee wall when I can pull all of the junk out of there.
> 
> I sealed up some big leaks. It's sassyfying.
> 
> Matt


 
Way to go Matt. That's a good feeling.


----------



## woodgeek (Feb 18, 2013)

GaryGary said:


> I measure the pressure difference from house to outside with a $10 ebay Dwyer Magnehelic pressure gage that goes 0 to 0.2 inches of water -- so, its basically full scale at 50 Pa. These gages are really nicely made and seem to always be available on ebay. Working on a simple way to measure the flow rate so that I can estimate an actual Air Changes per Hour number.
> 
> 
> Gary


 
Why not a length of (big) round duct, with a anemometer, or a pitot tube and a second dwyer to measure the velocity at the end?


----------



## GaryGary (Feb 18, 2013)

woodgeek said:


> Why not a length of (big) round duct, with a anemometer, or a pitot tube and a second dwyer to measure the velocity at the end?


 
I've attached an about 2 ft long rectangular duct to the fan outlet and measured the flow velocity with a Kestrel anemometer.  The problem is that there is a whole lot of variation in velocity across the section.  There is about a 3 to 1 difference from highest to lowest measurements as I move the Kestrel around.  Its also not the velocity profile you would expect in a duct -- its higher on the two edges parallel to the blower shaft with much lower velocities in the center -- just too close to the fan I guess.

I also have this very nice antique Alnor Velometer from ebay -- its basically a pitot tube with an analog pressure meter that reads out directly in velocity.  Has several probes and ranges.  Just as an aside, these are available on ebay for about $100 and in addition to being a nice piece of history, they are quite functional -- I'd guess they would be north of $2K if still offered today. 

In my anal engineer way, I did a 75 point velocity survey yesterday with the Velometer, and I can used it to get (I think) a good average velocity and flow.  The flow on high speed is about 2500 cfm.  I think I can use this survey and a single pitot tube reading to correlate this to other conditions.

I would like to work out a simpler way to do this, and a way that someone with just a Kestrel or the like could make descent measurements.  
If there was some way to even out the flow in the duct so that the velocity profile was more constant, that would be a big help -- any ideas?

Gary


----------



## woodgeek (Feb 18, 2013)

On the commercial blower doors, I thought the used a longer, collapsible flex duct to even out the flow.

Might find something like that as a 'play tunnel' at a big box toy store....?


----------



## semipro (Feb 18, 2013)

Gary,
You could build a venturi to measure flow. (image below).
Radial vanes place before the venturi could be used to create a straighter flow if needed.


----------



## GaryGary (Feb 18, 2013)

Sorry about polluting this thread with the blower door idea -- should have started a new thread.

So, thinking out loud about a simple way to get the blower flow out of the house at the standard blower door test depressurization of 50 Pascal...

The specs below are for a Fasco blower sold by Grainger -- I think the blower I have is quite similar.

When you look at the flow rates vs pressure drop for each speed, the flow rate drops very slowly as pressure drop is added. So with no load on high speed, the blower door does 2400 cfm, and with 0.3 inches of water (75 Pa) pressure drop, the flow is only down by 20 cfm to 2380 cfm. So, for the range of pressure for a blower door test (0 to 50 Pa), the blower flow rate is essentially constant (I think).

So, to determine the flow rate at 50 Pa (as is used in a standard blower door test), could I run the blower at high speed and note the house depressurization on by Dwyer gage (say its 75 Pa), then go down to low speed and note the new Dwyer gage reading (say its 20 Pa) -- then I could interpolate between the two readings to estimate the flow at 50 Pa?

So, in this example, with 2400 cfm at high speed and 1200 cfm at low speed, the flow at 50 Pa would be 1200 + ((50-20)/(75-20))(2400-1200) = 1855 cfm. Knowing the volume of the house, I could then calculate the Air Changes per Hour (ACH) at 50 Pa and be able to compare it to other standard blower door tests.

This assumes that all 1/2hp furnace blowers put out the same flow rates, and I'm sure this is not strictly true, but this Fasco is close to the 2500 cfm that I measured on my used 1/2 hp blower.

Gary

Edit: the blower data is easier to read at the Grainger catalog page at the link below.
*Item*
Blower
*Type*
Double Inlet Forward Curve, Direct Drive, With Motor
*Speed*
4
*Wheel Dia. (In.)*
10-5/8
*Wheel Width (In.)*
10-5/8
*CFM Range*
2400 to 230 @ 0.000-In SP to 1.700-In SP
*CFM @ 0.000-In. SP*
2400, 1800, 1450, 1220
*CFM @ 0.300-In. SP*
2380, 1760, 1420, 1185
*CFM @ 0.400-In. SP*
2350, 1750, 1410, 1180
*CFM @ 0.500-In. SP*
2335, 1720, 1395, 1170
*CFM @ 0.600-In. SP*
2300, 1675, 1365, 1150
*CFM @ 0.700-In. SP*
2210, 1650, 1300, 1080
*CFM @ 0.800-In. SP*
2130, 1550, 1220, 1010
*CFM @ 0.900-In. SP*
1900, 1390, 1125, 925
*CFM @ 1.000-In. SP*
1720, 1225, 1010, 790
*CFM @ 1.10-In. SP*
1440, 1030, 845, 620
*CFM @ 1.200-In. SP*
1160, 840, 650, 465
*CFM @ 1.250-In. SP*
955, 735, 570, 380
*CFM @ 1.30-In. SP*
750, 635, 490, 300
*CFM @ 1.40-In. SP*
540, 435, 340, 245
*CFM @ 1.500-In. SP*
430, 325, 240, 120
*CFM @ 1.600-In. SP*
320, 215, 150, -
*CFM @ 1.70-In. SP*
230, 100, -, -
*CFM @ 1.80-In. SP*
-, -, -, -
*Max. Inlet Temp. (Deg. F)*
104
*Max. Ambient Temp. (F)*
104

Catalog page: http://www.grainger.com/Grainger/ww...=true&toolbar=false&CatPage=4513&Catalog=main


----------



## woodgeek (Feb 18, 2013)

you could put a damper between the house (exhaust) and the blower inlet.  Then close down the DIY damper until the house pressure was -50 Pa.  Then you could read the pressure across the blower (which could now be different from 50 Pa due to the damper).  If you had a table of cfm versus pressure drop, you could convert to cfm.  And you would not have to assume that a house pressure was linear in cfm.


----------



## TradEddie (Feb 19, 2013)

Wow, if I had the spare time to do that, I would just work a couple of hours overtime and pay someone to do it properly. I have considered a homemade blower to try locate leaks, but actual quantitative results, that's professional work.

Slightly back on topic, my continued efforts have yielded mixed results. One unexpected "problem" is that I fixed two serious leaks in the room containing my thermostat, now the thermostat kicks in less often, so the rest of the house is noticeably colder!

Also, like most people burning wood, my biggest problem is heat distribution, and sealing leaks may make that even worse too.

Thanks for everyone's tips.

TE


----------



## EatenByLimestone (Feb 19, 2013)

Do you guys think that the orange Great Stuff will do a safe job around the chimney?  It's not used for the woodstove.  It's used for the NG boiler and traditional fireplace.  I doubt that even when the NG boiler is on it gets hot.  Other than that I don't know what could be used to seal the space around the chimney.  I have kaowool I can stuff in the crack, but it certainly won't stop the air from moving.  

Matt


----------



## GaryGary (Feb 20, 2013)

TradEddie said:


> Wow, if I had the spare time to do that, I would just work a couple of hours overtime and pay someone to do it properly. I have considered a homemade blower to try locate leaks, but actual quantitative results, that's professional work.
> 
> Slightly back on topic, my continued efforts have yielded mixed results. One unexpected "problem" is that I fixed two serious leaks in the room containing my thermostat, now the thermostat kicks in less often, so the rest of the house is noticeably colder!
> 
> ...


 
I actually had my utility come and do a blower door test -- it was near to useless.

First they decided that the free blower door test would not be free because I had solar hot water -- try and figure that one out.

So, I paid a bit over $200 to have a couple guys rush around the place and do a pretty skimpy test.  They were rushed and there was just not enough time to really look for leaks and get a good idea what was going on with airflows and leaks.  
Then the written report never came through in spite of several phone calls.

This home made blower door will cost a tenth of what I paid for my useless test, and it will tell me a lot more about whats going on, and it will tell me if the leak sealing I do actually has a positive effect, and which leaks were most significant.  I think there is real value in having the blower door available over the full time you are working on leaks -- that could be months working on it a bit at a time.

They tend to make the whole blower door thing out to be rocket science, but its very simple stuff, and the furnace blower based blower door only took a couple hours to build.  Figuring out how to calibrate it took a while, but only one person has to do that.

Gary


----------



## kingquad (Feb 21, 2013)

EatenByLimestone said:


> Do you guys think that the orange Great Stuff will do a safe job around the chimney? It's not used for the woodstove. It's used for the NG boiler and traditional fireplace. I doubt that even when the NG boiler is on it gets hot. Other than that I don't know what could be used to seal the space around the chimney. I have kaowool I can stuff in the crack, but it certainly won't stop the air from moving.
> 
> Matt


Use metal flashing and fire rated silicon caulking to seal the space around your chimney.  I wouldn't trust foam.  I think there are some free articles over on finehomebuilding on how to do this.


----------



## GaryGary (Feb 26, 2013)

hi,
I finished up the homemade blower door project and put up a few pages on it:
http://www.builditsolar.com/Projects/Conservation/BlowerDoor/BlowerDoor.htm

It works well -- I just need to get busy and start using it on my house now.

Thanks for the suggestions on the flow measuring issues.

Gary


----------



## milleo (Feb 26, 2013)

Wow nicely written, that should help lots of people out, right now I walk around in my bare feeties to find my air leaks Lol.


----------



## woodgeek (Feb 26, 2013)

GaryGary said:


> hi,
> I finished up the homemade blower door project and put up a few pages on it:
> http://www.builditsolar.com/Projects/Conservation/BlowerDoor/BlowerDoor.htm
> 
> ...


 
Very nice explanation....I like the ^0.65 power law! Coincidentally....I scheduled my first energy audit today for March 14th.


----------



## TradEddie (Feb 27, 2013)

I never really thought about the numbers before, but now I suppose my plan to use my old insert blower (200cfm?) to depressurize and look for leaks isn't going to work as well as I thought.
One thing to watch, those magnahelic gauges are only as accurate as their calibration, and I wouldn't trust the accuracy of one I bought online without verifying it against something else first.

Thanks for the ideas.

TE


----------



## semipro (Feb 27, 2013)

One relatively simple way to get strictly relative readings of air tightness might be to use a fan like the one Gary used and monitoring the change in amperage as improvements are made.  Centrifugal fans (squirrel cage) actually pull less current as flow decreases.

Gary,  could you try opening a window and measuring amperage while yours is running to validate?


----------



## TradEddie (Feb 27, 2013)

Another way to gauge relative tightness, and which wouldn't depend on calibration accuracy would be to record the ultimate pressure reached by the fan at any given speed setting, more tightness, lower pressure. You could close doors in the house sequentially, block the bottom with a towel and see which rooms made the biggest difference, focus on those first.

TE


----------



## GaryGary (Feb 27, 2013)

semipro said:


> One relatively simple way to get strictly relative readings of air tightness might be to use a fan like the one Gary used and monitoring the change in amperage as improvements are made. Centrifugal fans (squirrel cage) actually pull less current as flow decreases.
> 
> Gary, could you try opening a window and measuring amperage while yours is running to validate?


 
Hi, 
I'll try to remember to include measuring the amperage when I get to doing the house with the blower door, but its going to be a couple weeks as we are away for a while.

I just found out about the less current at lower flows today, and along with it that furnace blowers are actually designed work into some pressure load (the back pressure from the duct system), and that some of them may draw too much power if they have no pressure load on them at all.   I measured the amperage on mine and it was indeed somewhat above the motor nameplate amperage, and if I added a little resistance it dropped down to the nameplate value.  I'll probably just add a little resistance to keep the amperage down toward the nameplate value.  Added a note to the writeup alerting people to this.

Eddie: That is one thing I like about the old fashioned water or oil manometers is that they really can't go out of calibration (unless gravity changes).  I think that Dwyer oil manometer that only costs $34 new from Dwyer would do a good job.

Gary


----------



## semipro (Feb 28, 2013)

GaryGary said:


> I just found out about the less current at lower flows today, and along with it that furnace blowers are actually designed work into some pressure load (the back pressure from the duct system), and that some of them may draw too much power if they have no pressure load on them at all. I measured the amperage on mine and it was indeed somewhat above the motor nameplate amperage, and if I added a little resistance it dropped down to the nameplate value. I'll probably just add a little resistance to keep the amperage down toward the nameplate value. Added a note to the writeup alerting people to this.


I and others have been using these fans for shop ventilation as they're quiet and usually free since you can get them from old air handlers.  You can restrict either the inlet or outlet to get the proper amperage. 
We use one for a whole house fan and I built that restriction into the fan enclosure.


----------



## RustyShackleford (Feb 28, 2013)

kingquad said:


> Use metal flashing and fire rated silicon caulking to seal the space around your chimney. I wouldn't trust foam. I think there are some free articles over on finehomebuilding on how to do this.


What about using foil duct tape ?   I wonder if it can withstand the heat of chimney pipe ?   I doubt it'd melt, but maybe the adhesive drys out and it becomes brittle and falls off ?


----------



## kingquad (Mar 1, 2013)

RustyShackleford said:


> What about using foil duct tape ? I wonder if it can withstand the heat of chimney pipe ? I doubt it'd melt, but maybe the adhesive drys out and it becomes brittle and falls off ?


You're correct. The adhesive wouldn't hold up.


----------



## woodgeek (Mar 1, 2013)

I've had an ongoing problem sealing my block-off plate to the masonry.....so I googled around and ordered this 'flue tape'...

http://www.amazon.com/gp/product/B00004Z4DS/ref=oh_details_o00_s00_i00?ie=UTF8&psc=1

rated to 600°F, better than the black silicone!  I'll let you know if its junk.

In a hidden attic setting, I would still stick with sheet metal and black silicone (and I did).


----------



## kingquad (Mar 1, 2013)

In my old house, I secured the flashing to the chimney with tapcons.  Then, I ran a large bead of silicon around the edges.  I never had any problems.


----------



## RustyShackleford (Mar 1, 2013)

woodgeek said:


> ... ordered this 'flue tape'...
> 
> http://www.amazon.com/gp/product/B00004Z4DS/ref=oh_details_o00_s00_i00?ie=UTF8&psc=1
> 
> rated to 600°F, better than the black silicone! I'll let you know if its junk.


That looks like the shizzle, but remarkably similar to the foil duct tape; please let us know !

What is "black silicon" ?   The high temp silicon caulk that I got is red - from the auto parts store, to install a BK thermostat to replace mine with the reverse-wound coil.



> In a hidden attic setting, I would still stick with sheet metal and black silicone (and I did).


I have sheet metal around mine now, but maybe a 1/4" gap.   I'm afraid the silicon would droop through (I'd apply it from the attic).   So something temporary while it cures - maybe that tape that woodgeek found.


----------



## semipro (Mar 1, 2013)

RustyShackleford said:


> I have sheet metal around mine now, but maybe a 1/4" gap. I'm afraid the silicon would droop through (I'd apply it from the attic). So something temporary while it cures - maybe that tape that woodgeek found.


How about using the orange high temp spray foam?


----------



## woodgeek (Mar 1, 2013)

RustyShackleford said:


> That looks like the shizzle, but remarkably similar to the foil duct tape; please let us know !
> 
> What is "black silicon" ? The high temp silicon caulk that I got is red - from the auto parts store, to install a BK thermostat to replace mine with the reverse-wound coil.
> 
> ...


 
Yeah...just hi temp silicone...various colors I guess.  I left a smaller gap at my chimney and the silicone just sat there.


----------



## jebatty (Mar 2, 2013)

Perhaps I'm a little old school. Between the living room wood stove that heats our entire 1500 sq ft house, a large wood fireplace (which has a chimney damper), 2 bathroom and 1 kitchen exhaust fans, and 1 electric dryer, all of which move inside air to the outside, my house can't be too tight on air leaks. Maybe small leaks scattered around are better than a tight house and a heat recovery unit with variable fresh air supply based on air exhaust levels. A '56 house on which I have done a lot to make it tighter than it was, but I tend to measure "tightness" by how much wood we have to burn in the winter to keep the house warm and whether or not I need to crack a window to get good stove draft. For our cold climate, 4 cords of aspen/pine for the wood stove during a typical northern MN winter seem a pretty good measure of both fairly low heat loss and acceptable air infiltration for fresh air supply. The only time a window needs to be cracked for the wood stove to draft well is when outside temps get into the high 20's and above, and then only sometimes, probably when other exhaust fans are operating, although I don't pay too much attention to exactly when I need to crack a window. We don't notice drafts in our house, so I would guess that air leaks are small and scattered.


----------



## woodgeek (Mar 2, 2013)

Indeed. There are a lot of indications of air infiltration to those who pay attention. Myself, I use a humidifier index....I can keep my house at 30%RH in the dead of winter (not MN cold, 20s) using a 2-3 gallons of water per day.  Before I tightened up, couldn't bump the humidity at all. 

I just keep thinking about the guy who owned my 1960 house previously....he clearly must have known that his house was an 'energy hog' (i.e. >1000 gallons oil/yr) and went berserk weatherstripping all the doors and windows to get them airtight, all the while with huge openings in his attic sucking all the heat out of the house.

By the same token....why mess around with indoor air quality?  You can prob get a pro to come out and blower door your house for free from your utility...and (s)he will tell you whether you still have room for improvement, and where that might be, or alternatively, that you might want to add some ventilation for health.


----------



## EatenByLimestone (Mar 2, 2013)

I finally got upstairs into the knee wall to get a look at the canyons around the chimney so I could figure out what to do.  I'm not crazy about cutting flashing and screwing it to the framing, but without getting up there to look at it I don't know what I might do to seal it.  One of the things that bothers me about the idea is that Al flashing really doesn't retard heat loss.  

After getting up there I think I've figured out a way to do it without the flashing.  All of the talk about the foil tape above helped me get there.

I was looking at the cracks thinking if I had something that I could stuff in the cracks that was fire safe I'd only have to lay a thick bead of caulk over it and it would be sealed without dealing with tin snips.  I remembered that I had some kaowool blanket left over from a few stove insulations and tweaking sessions.  That will insulate, but not stop the air flow.  The caulk should lay on top of it to stop air flow.  Now for the foam tape stuff.  I also have foil backed kaowool blanket that is still wrapped around about 4 feet of extra chimney liner I have.  I can stuff that along the roof with the radiant barrier down so it will reflect the heat back into the house.  It also gives a nice spot for me to seal around with the fireproof caulk.  The 3M stuff I picked up also says it expands a bit.

While at Lowes I walked past the insulation section and Roxul had a representative there.  I decided to pick his mind and asked about chimneys.  He had only been working there for 3 weeks so he didn't have any ideas to help.  *rolls eyes*  At least he was honest and gave me the customer service number to call.  He seemed like a pretty good kid, just new on the job.  My 3 year old was making him nervous by grabbing for his display rocks.  Yes, he had rocks for props.  Maybe he thought she was going to break them.  I had her sit on the floor where she wouldn't make the guy nervous.  He said his other job was doing birthday parties for kids.  *shrug*


Matt


----------



## EatenByLimestone (Mar 2, 2013)

I finally got upstairs into the knee wall to get a look at the canyons around the chimney so I could figure out what to do.  I'm not crazy about cutting flashing and screwing it to the framing, but without getting up there to look at it I don't know what I might do to seal it.  One of the things that bothers me about the idea is that Al flashing really doesn't retard heat loss.  

After getting up there I think I've figured out a way to do it without the flashing.  All of the talk about the foil tape above helped me get there.

I was looking at the cracks thinking if I had something that I could stuff in the cracks that was fire safe I'd only have to lay a thick bead of caulk over it and it would be sealed without dealing with tin snips.  I remembered that I had some kaowool blanket left over from a few stove insulations and tweaking sessions.  That will insulate, but not stop the air flow.  The caulk should lay on top of it to stop air flow.  Now for the foam tape stuff.  I also have foil backed kaowool blanket that is still wrapped around about 4 feet of extra chimney liner I have.  I can stuff that along the roof with the radiant barrier down so it will reflect the heat back into the house.  It also gives a nice spot for me to seal around with the fireproof caulk.  The 3M stuff I picked up also says it expands a bit.

While at Lowes I walked past the insulation section and Roxul had a representative there.  I decided to pick his mind and asked about chimneys.  He had only been working there for 3 weeks so he didn't have any ideas to help.  *rolls eyes*  At least he was honest and gave me the customer service number to call.  He seemed like a pretty good kid, just new on the job.  My 3 year old was making him nervous by grabbing for his display rocks.  Yes, he had rocks for props.  Maybe he thought she was going to break them.  I had her sit on the floor where she wouldn't make the guy nervous.  He said his other job was doing birthday parties for kids.  *shrug*


Matt


----------



## EatenByLimestone (Mar 2, 2013)

One side is caulked at the top and bottom. I have KW stuffed vertically between the chimney and framing but it isn't caulked yet. Either the wind stopped blowing or I got a leak. Now to do the easy side.


Update:  The chimney is done.  5 tubes of firecaulk were used.  That stuff is expensive!  I did 2 seals.  One at the roof/ceiling of the kneewall and one at the floor to stop air from coming up from below.  2 more cans of foam were used sealing additional cracks and crevices in the front kneewall.  I noticed that it was a bit cool by the chimney when I went in there this morning compared to the rest of the floor.  It was much warmer in there when I put the insulation back in the framing when I got done.  I haven't stapled it back up though.  The staple gun jammed and my kneed hurt a bit from kneeling so long.  I'll get everything finished tomorrow.   

By the way, does anybody know a tape that sticks well to kraft faced insulation seam?  

Mat


----------



## EatenByLimestone (Mar 9, 2013)

Update:

The 2 areas that lost the most heat were the chimney and the interior wall area that was drafting into a small unheated space above a room.  We had about 6 inches of snow Friday, followed by a sunny ~50F day today and both areas are still showing lots of snow.  SUCCESS!

There is a small area that is snowless about the size of a basketball a little further down.  I'm pretty sure this is a spot where the kraft paper is all ripped up.  I'll be fixing that tomorrow.  

Matt


----------



## TradEddie (Mar 13, 2013)

So here's the end result, 10 years of effort to reduce my bills.
Gallons of propane and btu/hdd/sqft, based on actual season hdd.
It's hard to sort out the various factors which can affect consumption, certainly there is variation in our use pattern from year to year depending on babies, sick days, snow days, vacations, unemployment etc., but the trend is clear and none of the improvements below are from sacrificing comfort. Wood use is not shown, but was probably steady with the old slammer and significantly reduced now.
Improvements made:


Replacing most 1970's sashes with identical or High Perf/Low E.
Air sealing and insulating rim joist where accessible.
Air sealing - utility penetrations, receptacles, kneewalls.
Installing exterior door at basement Bilco door entrance
Insulating floor of crawlspace behind cape kneewalls.
Sealing access doors of knee walls.
Insulating supply ducts in basement, sealing boots at duct, and at registers
Insulating behind brick wall to garage
The only expensive part of this was the windows, these were replaced as necessary for rot and damage, and on a priority basis. The rest was barely $50 at a time, one or two projects each year. Problem now is that all the easy jobs are done.


----------



## RustyShackleford (Mar 13, 2013)

How are people sealing electrical boxes ? There's two sources of leakage: between the edge of the box and the drywall, and through the knockouts (especially the ones knocked-out for wires to pass) into the box and thence into the house.

The first is easily dealt with by caulking. The second is typically addressed by the little foam gaskets, but these don't seem like they seal very well to me, and I've read they're next to worthless. In a small addition, I am trying to get ahead of the game by caulking around the knockouts before the insulation and drywall go up. This can't be done later, because it's a no-no to put caulk inside the box, although I suppose a little discretely applied would be fine if it doesn't use up appreciable volume in the box and if you can figure out how to actually do it.

So I'm caulking the heck out of the wires on the outside, but I'm worried that when the outlets and switches go in, all that tugging and pushing on the wires will cause the caulk to fail. I thought of installing the fixtures BEFORE the drywall, but apparently that's considered a pretty bad idea.   I've heard of something called "putty pads", but I don't know if they'd work any better or not.


----------



## TradEddie (Mar 13, 2013)

Those foam pads are useless, most receptacles allow air through the body and out the pin holes, so you'd have to plug unused outlets with those child safety covers. I used caulk rope on the knock outs where I could, would love better ideas. Wherever I could access the wire penetrations from the basement, I plugged those too.

TE


----------



## DickRussell (Mar 14, 2013)

RustyShackleford said:


> How are people sealing electrical boxes ? There's two sources of leakage: between the edge of the box and the drywall, and through the knockouts (especially the ones knocked-out for wires to pass) into the box and thence into the house.


 
Rusty, if this is new construction you are describing, you can do one of two things to address box leakage. Lessco makes a flanged polypan that goes onto the framing first, with the electrical box mounted inside that. Airfoil makes a nice box with a wide flange all around and with two narrow pockets outside the main box volume for wire sealing with a squirt of can foam after wire is run. There may be a similar product out there now; I seem to recall reading about it. With either product, the drywall is sealed to the flange with either acoustical sealant or gaskets. This seals the box and its contents on the room side of the air barrier.

I used the Airfoil boxes on exterior walls in my house, with Certainteed MemBrain as the vapor retarder. I tape-sealed the MemBrain to the Airfoil box flanges. There is NO air leakage through that assembly, for all practical purposes.


----------



## RustyShackleford (Mar 14, 2013)

Thanks for the suggestions, but I've already done the electrical rough-in (and I'm not gonna rip out my makeup to put in better boxes     I thought of pigtailing the outlet boxes, so I'm not disturbing the cables coming into the boxes much when I install the fixtures - and it's considered good policy by some anyhow.


----------



## nate379 (Mar 14, 2013)

Good question.  The boxes on teh outside wall of my house are fairly leaky.  Wouldn't foam be bad... fire hazard?


----------



## RustyShackleford (Mar 14, 2013)

nate379 said:


> Good question. The boxes on teh outside wall of my house are fairly leaky. Wouldn't foam be bad... fire hazard?


I asked about this is one of the electrical forums and they seemed to think not a problem, pointing out that when people insulate the wall stud cavities with spray foam, the outside of the box is pretty much buried in the stuff.    Putting spray foam INSIDE the box is definitely a no-no, if for no other reason than it uses up volume in the box and the NEC makes a big deal about a box having enough room for the number of wires etc.

My main concern about caulking, as I said, is that when installing the fixtures, all the stress on the wires may break the caulk loose.

Called the local specialty electrical supply house and they have weatherproof boxes - supposedly a flange and rubber seal where the cables enter (perhaps the same as discussed above ?).   They don't sound terribly expensive either, so I'm gonna go check 'em out, and maybe rip out my rough-in after all, at least on a few of the exterior-wall boxes where the only thing connected so far is the grounds.


----------



## seige101 (Mar 14, 2013)

Acoustic caulking remains flexible or a 100% pure silicone applied liberally should do the trick for you


----------



## RustyShackleford (Mar 14, 2013)

seige101 said:


> Acoustic caulking remains flexible or a 100% pure silicone applied liberally should do the trick for you


If you're responding to my concern, thanks - but, even a caulk that remains flexible could be a problem.   Typically, when connecting fittings (or jamming all the wires back in the box when you're done), you'll end up pulling or pushing the Romex (usually pushing, I find).   If the caulk plug breaks loose and decides to stick to the Romex instead of the box, you may end up with no air-sealing at the knockout, and a caulk plug attached to the Romex 1" before it enters the box.   If the caulk stays attached to the box, you're probably golden.

I've also read that silicon caulk can conceivably degrade certain plastics, so due to the safety concerns, I'm reluctance to apply it toRomex.   I've also read that the non-acetic acid containing silicon, such as GE Silicon II caulk, does not contain acetic acid and probably doesn't have this issue.   For the same reason, I intend to usee Silicon II around my glass IGUs.


----------



## seige101 (Mar 14, 2013)

RustyShackleford said:


> . Typically, when connecting fittings (or jamming all the wires back in the box when you're done), you'll end up pulling or pushing the Romex (usually pushing, I find)..


 
Electrician is my day job  They also do make a fire rated touch and foam you can cover the knockouts/cables in. You could also try fire caulk if you have concerns about it reacting to the sheathing on the romex. There are several different kinds some get hard like concrete and others stay relatively soft. Never had a problem using 100% silicone with romex. (I like to caulk the wire where it goes outside the building for water proofing and air sealing)


----------



## seige101 (Mar 14, 2013)

Also to add i have seen these boxes at the supply house recently, i have no experience using them but figured i would pass it along. http://www.alliedmoulded.com/index....egory/template/products_sub_res/categoryid/46


----------



## RustyShackleford (Mar 15, 2013)

Thanks for the link seige101. I don't think those are the boxes the place here had, because they said they actually have a rubber seal on the knockouts - the instructions for the ones you linked still specify caulking the knockouts. I'm gonna go look, and probably buy, some of these tomorrow - I'll report back.

The caulking I've done thus far has been with the DAP Dynaflex 230, the same stuff I'm caulking my framing joints with. But I expect you're right that the concern with silicon causing problems is silly. I still intend to use Silicon II on my expensive IGUs though - it's only like a buck more per tube, and it doesn't stink as badly.


----------



## RustyShackleford (Mar 16, 2013)

RustyShackleford said:


> I don't think those are the boxes the place here had, because they said they actually have a rubber seal on the knockouts - the instructions for the ones you linked still specify caulking the knockouts. I'm gonna go look, and probably buy, some of these tomorrow - I'll report back.


Ok, got my boxes. The boxes have a lovely flange, about 1" wide, around the perimeter, with a spongy gasket for the drywall to compress against. And they mount using angled screws that are inside the box. They're big too, 22 and 42 cu-in for the 1- and 2-gang, respectively.  Each box had a few holes, and then plastic pieces to seal the holes and/or allow wires to pass through.   There was also a little stick-on rubber seal thingy  that sticks to the box outside each hole. So the seal is far from perfect, but still a lot better than regular boxes. They are Arlington F101F and F102F, $2.24 and $7.41.

http://www.aifittings.com/products/spec-sheets/VAPOR_BOXES.pdf


----------



## EatenByLimestone (Mar 16, 2013)

TradEddie said:


> View attachment 96772
> 
> So here's the end result, 10 years of effort to reduce my bills.
> Gallons of propane and btu/hdd/sqft, based on actual season hdd.
> ...


 
That's awesome!  You're saving 1200 bucks a year from your efforts!  

The last year my father heated this house and burnt 700 gallons of oil.  I then inherited it and cut it down to 400 something by keeping it a bit cooler and doing some insulation work and windows.  I then switched to gas as I saw the writing on the wall for oil.  At that time the house was around 900 sq ft.  I've since built out the attic and added 50% to the size of the house.    

I put the up the rest of the foam and half taped the final 15 feet of the front of the house today.  I'll wait until the Great Stuff around the edges seals and then finish taping the rest of it.  We had a dusting of snow last night and I could really see the difference on where the snow melted.   All of the heat I was loosing on the front was pushed to those 15 feet.  It really made that part of the roof look bad.  By the end of today or early tomorrow any leaks on the front of the house will be from below the floor level.  I'm a bit excited to see what happens when we get 2-4"of snow Monday or Tuesday.

Matt


----------



## TradEddie (Mar 17, 2013)

EatenByLimestone said:


> That's awesome! You're saving 1200 bucks a year from your efforts!
> 
> The last year my father heated this house and burnt 700 gallons of oil. I then inherited it and cut it down to 400 something by keeping it a bit cooler and doing some insulation work and windows. I then switched to gas as I saw the writing on the wall for oil. At that time the house was around 900 sq ft. I've since built out the attic and added 50% to the size of the house.
> 
> ...


I'd more realistically put it at about $400/yr, those early years had more heating demand for sure, e.g. 2005 my wife was at home with a baby for 3 months. The very odd thing about that chart is when I realized that in 2006 we finished 400sqft of basement, adding 20% to our heated area, but it had no adverse effect on out heating bill, possibly the opposite, I'm wondering if the incidental benefit of insulating almost half of the basement perimeter and more than half of the basement floor balanced out the increased heating space. 
We had a dusting of snow/ice yesterday and it was nice to see the obvious benefits on my roof where I'd fixed some problems just a few weeks ago. I used to have a huge clear spot in the middle of the roof from an open joist bay, now blocked.

TE


----------



## semipro (Mar 17, 2013)

TradEddie said:


> We had a dusting of snow/ice yesterday and it was nice to see the obvious benefits on my roof where I'd fixed some problems just a few weeks ago. I used to have a huge clear spot in the middle of the roof from an open joist bay, now blocked


I also recently identified a trouble spot by inspecting the roof after a snow. (quite by accident actually).
The problem turned out to be a lack of insulation in a cathedral ceiling where an interior wall met the roof.


----------



## laynes69 (Mar 17, 2013)

It's amazing the amount of energy one can save by doing some detective work. We still have ways to go. At one time our home required 2- 150,000 btu oil furnaces, and after insulation and air sealing we have a heat loss of around 75,000 BTUs at 0 degrees. After this spring and summer, those numbers will hopefully be reduced.


----------



## EatenByLimestone (Mar 17, 2013)

TradEddie said:


> I'd more realistically put it at about $400/yr, those early years had more heating demand for sure, e.g. 2005 my wife was at home with a baby for 3 months. The very odd thing about that chart is when I realized that in 2006 we finished 400sqft of basement, adding 20% to our heated area, but it had no adverse effect on out heating bill, possibly the opposite, I'm wondering if the incidental benefit of insulating almost half of the basement perimeter and more than half of the basement floor balanced out the increased heating space.
> We had a dusting of snow/ice yesterday and it was nice to see the obvious benefits on my roof where I'd fixed some problems just a few weeks ago. I used to have a huge clear spot in the middle of the roof from an open joist bay, now blocked.
> 
> TE


 

I bet it did balance it out.  You stopped the cold air coming in from ground level.  I have plans to do that in the future, but other than new windows down there it isn't happening anytime soon.  I've got to fix a water issue first.  I'm going to hope and pray that gutters will solve it.  If they prove successful then I'll insulate from the outside.  If they don't I'll have to excavate down to the footer, put in a drain and then insulate all in one shot.  I really don't want to do that.  I'd rather have it dry then insulate the top 4 feet with a sheet of foam.  I don't know what I'd cover it with though.  Maybe a parge coat of some sort.  

Now I need to keep an eye on the south facing side of the house.  There are 2 short sections of knee wall there.  I don't remember them showing lots of leakage, but now that the front leaks have been plugged they might become the next largest issue.  

I wish I had an IR camera.  It's going down to 14 tonight, it would really show where the heat is leaving the house.


----------



## EatenByLimestone (Mar 17, 2013)

laynes69 said:


> It's amazing the amount of energy one can save by doing some detective work. We still have ways to go. At one time our home required 2- 150,000 btu oil furnaces, and after insulation and air sealing we have a heat loss of around 75,000 BTUs at 0 degrees. After this spring and summer, those numbers will hopefully be reduced.


 

Great job!  What kind of things are you working on now that you cut out so much leakage?

Do those big oil burners short cycle now or are you totally on wood or pellets?  

Matt


----------



## milleo (Mar 17, 2013)

EatenByLimestone said:


> I bet it did balance it out. You stopped the cold air coming in from ground level. I have plans to do that in the future, but other than new windows down there it isn't happening anytime soon. I've got to fix a water issue first. I'm going to hope and pray that gutters will solve it. If they prove successful then I'll insulate from the outside. If they don't I'll have to excavate down to the footer, put in a drain and then insulate all in one shot. I really don't want to do that. I'd rather have it dry then insulate the top 4 feet with a sheet of foam. I don't know what I'd cover it with though. Maybe a parge coat of some sort.
> 
> Now I need to keep an eye on the south facing side of the house. There are 2 short sections of knee wall there. I don't remember them showing lots of leakage, but now that the front leaks have been plugged they might become the next largest issue.
> 
> I wish I had an IR camera. It's going down to 14 tonight, it would really show where the heat is leaving the house.


Gonna be colder in southern maine tonight....What is going on here? Alaska warmer than Maine...Makes no sence to me!


----------



## EatenByLimestone (Mar 17, 2013)

semipro said:


> I also recently identified a trouble spot by inspecting the roof after a snow. (quite by accident actually).
> The problem turned out to be a lack of insulation in a cathedral ceiling where an interior wall met the roof.


 
I had this happen.  My problem was made worse by having a number of outlets, a hardwired CO/smoke detector and subpanel in the wall.  I had to open up the wall, create a temporary floor across the hole by stuffing in paper towels into it, and then foam the heck out of it.  The paper towels stopped the foam from falling down into the wall cavity.  It pushed the leak over to the knee wall area so I had to seal that area also.   

Matt


----------



## milleo (Mar 17, 2013)

milleo said:


> Gonna be colder in southern maine tonight....What is going on here? Alaska warmer than Maine...Makes no sence to me!


Opps you no in Alaska or are you?


----------



## EatenByLimestone (Mar 17, 2013)

I'm in Schenectady, NY.   We're about 15 minutes west of Albany.  

Matt


----------



## milleo (Mar 17, 2013)

EatenByLimestone said:


> I'm in Schenectady, NY. We're about 15 minutes west of Albany.
> 
> Matt


Lol....It's still gonna be cold here tonight, especially for this time of year.


----------



## laynes69 (Mar 17, 2013)

Well, it's a long story. Before my father bought this home from my grandparents, it was a wreck. Before it was insulated in '79, grandpa had the furnaces installed. His bill in the 70's got as high as 700 a month with the dual furnaces. He had the walls insulated with urea formaldehyde foam by my father in '79, which cut his bill in half. When dad bought the home, half the windows were shot (rotted or cracked), so the lower ones were replaced by vinyl double hung-double pane windows, then the upper windows in '93 (we have 42 on the house). Dad also had the attic insulated in '93, but paid no attention to airsealing. Over the next 10 years, it settled to only 3" of cellulose. He had concentrated on tearing out the walls with the deteriorating plaster and installing a vapor barrier and fiberglass. What he didn't concentrate on was airsealing. 

About 7 or 8 years ago, we bought the home. I had to install a full duct system to heat the upstairs, which had a 20 degree difference from downstairs. I've torn out a few rooms, and concentrated on airsealing with fiberglass batts, vapor barrier and drywall. The rooms I've done, even at 0 degrees are warm ( we have 8" walls). I've airsealed the attic, crawling on my hand and knees inspecting the entire attic from the middle to end, and sealing any voids or cracks. I cleaned out each crack to allow for either foam or caulking to penetrate the leak. I capped 32 open cavities (balloned framed home) in the attic, and I added 12" on top of the 3" that was there. I've installed foam gaskets, insulated and sealed all hidden ductwork, and went around the base of the exterior walls looking for openings or voids. 

Currently I need to tear off our old laundry room which is rotten and squirrels have been entering. It will eventually become a 2 story addition. In the winter, it feels like an airconditioner running with a box fan. Our den is half torn out, exposed lathe and plaster and the room above it needs gutted for a bathroom. I want to build an insulated door for the basement (extremely leaky), spray foam where the walls meet the foundation and tear out some of the already replaced walls where air sealing wasn't done. I also want to finish insulating the ductwork in the basement. We had an energy audit done, and while our home was very leaky (I can smell fresh air when it's windy), the neighbors new home down the road was leakier. Not bad for a mid 19th century Victorian. I've done a ton of work, and it's payed off greatly, but like I say there's plenty more.

I forgot to add, we have a 90% efficient propane furnace that's about 25 years old with little use. Our old woodfurnace would use up to 10 cord or more and we would use half a tank (200 gallons of propane or more) a season. Since I airsealed, insulated the attic and replaced the woodfurnace with a EPA model, I've been able to heat 100% with wood. I've burned about 5.5 cords this year since September and the home averages 72-75 depending on weather. The 1200 sqft basement stays in the mid 60's while the 2 floors above remain in the 70's.


----------



## EatenByLimestone (Mar 22, 2013)

That's impressive!  I wonder how low you can get those bills?  

On Monday and Tuesday we had about 8" of wet snow.  A few sunny 40 degree days later the side I finished working on has a full coat of snow except for a few little spots right at the bottom of the roof.  Since the rafters have been sealed to the floor with foam I think the spots are from warm air moving up inside the exterior walls.  There isn't much I can do about that now.  I think my efforts are better spent on the South facing roof and then on the basement.  

Matt


----------



## semipro (Mar 23, 2013)

RustyShackleford said:


> How are people sealing electrical boxes ? There's two sources of leakage: between the edge of the box and the drywall, and through the knockouts (especially the ones knocked-out for wires to pass) into the box and thence into the house.
> The first is easily dealt with by caulking. The second is typically addressed by the little foam gaskets, but these don't seem like they seal very well to me, and I've read they're next to worthless. In a small addition, I am trying to get ahead of the game by caulking


Rusty, are you going for "airtight drywall" as an interior air barrier?
http://www.finehomebuilding.com/how-to/departments/energy-smart-details/airtight-drywall.aspx

Or, do you already have an external air barriers such as housewrap?

I guess what I'm getting at is that its best to establish one really good air barrier somewhere whether exterior, in the wall, or interior.
Trying to fix a leaky exterior air barrier by sealing inside isn't really going to help much. There are just too many places where the air can make its way in (baseboards areas, etc).
Interior air barriers only work well when done during framing and wallboard installation because all connections between materials have to be sealed somehow.

After chasing infiltration from the inside with outlet sealing etc. for years I realized that I was wasting my time. Once I started concentrating on the outer air barrier, one I could actually get to directly, I started making real improvements.


----------



## RustyShackleford (Mar 23, 2013)

semipro said:


> Rusty, are you going for "airtight drywall" as an interior air barrier?
> http://www.finehomebuilding.com/how-to/departments/energy-smart-details/airtight-drywall.aspx


Yes.



> Or, do you already have an external air barriers such as housewrap?


I have that too. But of course it's not perfect, most notably at the top and bottom. I've also tried to make the external barrier better by caulking all the framing joints before the insulation was installed. And yes, I realize it's a really bad idea to have a vapor barrier on both the interior and the exterior. In fact, here the in hot humid southland, where it's frequently more hot and humid outside the house than inside, the usual wisdom of an indoor vapor barrier is explicitly counter-recommended by the building inspector's office.   So I have neither.




> Interior air barriers only work well when done during framing and wallboard installation because all connections between materials have to be sealed somehow.


Exactly. I guess I failed to mention that this was new construction - a small addition on the rear of my house.


----------

