hey, thats sounds good. now when you say place styrophom between the floor joists, should it be placed directaly up against the subfloor? Meaning, could I tack it up there somehow?
Cold floors/crawlspace
- Thread starter Henz
- Start date
-
Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.
We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.
We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil. -
Super Cedar firestarters 30% discount Use code Hearth2024 Click here
- Status
Adirondackwoodburner said:
Yes. Basically I was re-stating what Rhonemas already said, just in my own words. But I just happen to have the same design going on at my house.
The styrofoam would be placed right up against the subfloor. I simply took some long finish nails and held them up temporarily, then used spray foam on the borders which really locked it in. Then there is another layer of styrofoam on the bottom of the joists, hence creating a dead air space inbetween the two layers of styrofoam.
OK, I would love to be able to do that..I can do the tacking to the underside, but the attaching to the bottom of the joists..HA...what joists..these are all different sized hand hewn beams..some only half the size of the others..I should jsut create an entire new brace system at the same time./
There are insulation products that come in rolls too. I'm thinking of that silver bubble wrap stuff. Expensive, but may be the trick for you. Besides that, those 4x8 sheets come in various thicknesses. The thinner stuff is quite flexible. Maybe put up in layers?
Just tossing some ideas out.
Just tossing some ideas out.
YEAH, ITS ALL GOOD! ANOTHER VARIABLE IS THAT THE ONLY WAY FOR ME TO GET INTO THIS PARTICULAR SPACE IS THROUGH A 2'X3' ACCESS PANEL
I used R-19 fiberglass and have no problems. I think it's a good solution for the following reasons:
1) I have 6 mil poly on the floor so moisture is not a problem
2) I used "faced" insulation so I have some vapor barrier
3) fiberglass protects the faced portion so no additional covering is required over the craft paper faced side (flamable foams/styrenes require coverings, thus further preventing wood inspections/construction)
4) my crawl space is vented so, again, moisture is not a problem
5) fiberglass is cheaper than foam (I did 1200 sq ft of crawl with R-19 for $364 after rebates), doesn't require special tools to install, can be done by the "week-end warrior", works fairly well, doesn't burn, mold or mildew and can be easily removed for inspection or to do additional construction
6) Also, a few strategically placed tins of Decon take care of any rodent problems!!
1) I have 6 mil poly on the floor so moisture is not a problem
2) I used "faced" insulation so I have some vapor barrier
3) fiberglass protects the faced portion so no additional covering is required over the craft paper faced side (flamable foams/styrenes require coverings, thus further preventing wood inspections/construction)
4) my crawl space is vented so, again, moisture is not a problem
5) fiberglass is cheaper than foam (I did 1200 sq ft of crawl with R-19 for $364 after rebates), doesn't require special tools to install, can be done by the "week-end warrior", works fairly well, doesn't burn, mold or mildew and can be easily removed for inspection or to do additional construction
6) Also, a few strategically placed tins of Decon take care of any rodent problems!!
Sorry to dig up this month old thread, but...
I have an uninsulated tongue and groove plank floor above a dirt vented crawlspace. The 5/4 tongue and groove floor decking is supported every 5 or 6 feet with 4x12" floor joists running perpendicular. The T&G decking sets on top of a sill plate on the perimeter so no rim joist.
The crawlspace is accessed through a 2x2 foot concrete pit with a 2x2 foot opening to the crawl. This is to show that I can't just pull a sheet of foam down there. Maybe a 2' wide strip.
Caulk all the openings to the heated space, and resinstall the vapor barrier. OK. Then I have these huge joist cavities with planks above. I have heard that the T&G needs to be exposed to air so it can breathe, is this true? There is no vapor barrier on the concrete stem walls and certainly none beneath the sill plate extending to the outside like all the provided details show so I am not sure if I should just insulate the foundation and seal off the crawlspace.
I would like to use fiberglass beneath the planks since I can get the rolls into the crawlspace but the bays are so wide that I would have to hold the FG up with something else. I would expect the vapor barrier to face the T&G deck but I honestly don't remember seeing a vapor barrier on my previous homes between the FG and the subfloor.
What is the best solution?
Thanks
I have an uninsulated tongue and groove plank floor above a dirt vented crawlspace. The 5/4 tongue and groove floor decking is supported every 5 or 6 feet with 4x12" floor joists running perpendicular. The T&G decking sets on top of a sill plate on the perimeter so no rim joist.
The crawlspace is accessed through a 2x2 foot concrete pit with a 2x2 foot opening to the crawl. This is to show that I can't just pull a sheet of foam down there. Maybe a 2' wide strip.
Caulk all the openings to the heated space, and resinstall the vapor barrier. OK. Then I have these huge joist cavities with planks above. I have heard that the T&G needs to be exposed to air so it can breathe, is this true? There is no vapor barrier on the concrete stem walls and certainly none beneath the sill plate extending to the outside like all the provided details show so I am not sure if I should just insulate the foundation and seal off the crawlspace.
I would like to use fiberglass beneath the planks since I can get the rolls into the crawlspace but the bays are so wide that I would have to hold the FG up with something else. I would expect the vapor barrier to face the T&G deck but I honestly don't remember seeing a vapor barrier on my previous homes between the FG and the subfloor.
What is the best solution?
Thanks
I dont think that your gonna get any additional responses other than what is previously posted..You and I ahve the same exact problem..I thin that I am gonna caulk all of the seams and definately use rigid foam to insulate the crawl-space walls first. this will give me dead air space under my rooms where the crawl space is located. I am not going to actuallly insulate the floor directaly. I also only have alike a 2.5x2" access panel..I am gonna simply cut the 4'x8' sheets to fit through and then use alot of insulation tape to seal every seam.
- Nov 21, 2005
- 827
Boy, that sounds like a beauty. Honestly, about every thing I can come up with, will probably cost you about as much as having a professional going in there and covering the area with insulating foam, which will fill and expand into every crack & seam. Otherwise, it looks like
1.) Caulk the gaps in the groove floors
2.) Toe nail in some 2x3's or 2x4's to bridge the 5' gap and make sure they're flush with the bottoms, and there's no more than a 24" gap
3.) Cover the bottom with either 2" XPS foam, or 5/8" plywood and caulk/fill the seams. Either one you can cut to 2' wide
4.) Rent a blown cellulose machine and fill in the 12" space with it. I don't recommend not filling the dead space with cellulose but, there's good reasons not to. If you don't, any air penetrations will seriously hinder your insulation value.
Phew, what a job. I'd get a quote from a professional that can spray polyurethane insulating foam as that's not a job you probably want to do, and in the end I think the price will be comparible.
1.) Caulk the gaps in the groove floors
2.) Toe nail in some 2x3's or 2x4's to bridge the 5' gap and make sure they're flush with the bottoms, and there's no more than a 24" gap
3.) Cover the bottom with either 2" XPS foam, or 5/8" plywood and caulk/fill the seams. Either one you can cut to 2' wide
4.) Rent a blown cellulose machine and fill in the 12" space with it. I don't recommend not filling the dead space with cellulose but, there's good reasons not to. If you don't, any air penetrations will seriously hinder your insulation value.
Phew, what a job. I'd get a quote from a professional that can spray polyurethane insulating foam as that's not a job you probably want to do, and in the end I think the price will be comparible.
yeah I hear you there. I might try that route too. I wounder if they can spray that stuff directly onto the inside layed up stone foundation too???
In reading more about the non-ventilated crawlspace I am starting to like the concept. Ducting would be in a somewhat conditioned space and it would be much easier and cheaper than trying to fill all those big bays with insulation. The trick will be keeping it dry. All of the documents listing the "proper" way to seal the crawlspace all start with the vapor membrane beneath the sill plate. If I am able to seal up to the sill plate on the inside, do you think that I will be allright?
I would be insulating the inside of the stem wall and footing.
I would be insulating the inside of the stem wall and footing.
AWB I had the same issue. Cold floors, drafts coming up through the floors. Now we have a new foundation, caulked all the way around very carefully, then 1.5" styrofoam (milder climate) glued to the inside of the foundation and finally 6" fiberglass between the joists in the rim joist pocket at the ends. I thought about going with the spray foam on the walls, but it was a lot more money and this was something I could do myself. My sons and I did it all over a couple weekends. I am treating this as a conditioned space so all vents were sealed, caulked and insulated as well. The results are that the crawlspace doesn't go below 60 degrees even when well below freezing outside and the floors are much more comfortable.
thats basically what I am going to do..Insulate the inside of the rock foundation. that is my main air seepage..I can see through the dam nthing anyways..Plus the 3' open are isnt that good either!
BeGreen said:
Begreen: I see no mention of vapor barrier in your setup. Did you simply glue the XPS directly to the stem wall and leave the poly vapor barrier on the ground or did you do something else? Thanks so much.
- Nov 21, 2005
- 827
If you're adventerous you can get the "kit" yourself. Here's a company that sells the 2 system spray area foam system to homeowners. If you notice, the tanks have to be 75-85F but you can spray at any time. Just, make sure if the tanks cool below 75F time to warm them back up. Price looks pretty good from a quick glance, since I'm not thinking about purchasing I didn't put much effort into analyzing it. They even have videos for basement/crawl spaces, after watching them I may get that system for my rim joist/sill plate areas.
http://www.fomofoam.com
http://www.fomofoam.com
Your rock foundation doesn't leak in spring? Wouldn't that be a factor?
Since it's a crawl space no code requirement for covering the flammable Styro?
Since it's a crawl space no code requirement for covering the flammable Styro?
Highbeam said:
Yes, XPS is glued directly to the cement foundation walls. I put a new vapor barrier down after all other work was completed.
- Dec 19, 2006
- 55
I'm not sure where you are in the Adirondacks, but if you are Southwest of Blue Mtn. Lake you might try Standard Insulation in Utica. They did a great job on insulating my home a few years ago. Sprayed Foam was an option, but we were fearful of the possibility of my son's allergic reactions so we went with an inert blown in fiberglass solution.
tutu_sue said:
Problem with this is that your floors may still be somewhat cold because the ground is at about 55 and any heat radiating down from the floors into the crawlspace still "sees" the cold earth crawlspace floor. So, while your crawlspace warms somewhat it still never comes close to room temperature...... What I did was to insulate the underside of the floors with R-19 fiberglass and let the crawlspace temp float to whatever it wants........my crawlspace never freezes and yet I have crawlspace vents open year round.....I think part of the reason is that the heat ducts run through the crawlspace and even though they're taped and insulated, that residual heat from them provides some heat to the crawlspace.
Hi,
This is my third try at a reply...
I'm an insulation contractor. Check out Spray foam. It is the best choice for your situation. It come in 1/2lb and 2lb, $.40 and R-3.8 and $1 and R-6.8 per board foot in my area.
I prefer Demilec Heatlock and Sealecton500.
My other soulutions would include air sealing all penetrations in the floor, rim jois and sill with foam board and gun foam/caulk, with either foam board applied to the bottom of the floor as suggested earlier. Or insulweb or poly with dense pack celulose.
Check out the Demilec site and fill out the form for contractors certified to install their product in your area.
Feel free to e-mail me with other questions,
Garett
ps. Anything is better than FG especialy if it is in an open cavity. FG is better than nothing.
This is my third try at a reply...
I'm an insulation contractor. Check out Spray foam. It is the best choice for your situation. It come in 1/2lb and 2lb, $.40 and R-3.8 and $1 and R-6.8 per board foot in my area.
I prefer Demilec Heatlock and Sealecton500.
My other soulutions would include air sealing all penetrations in the floor, rim jois and sill with foam board and gun foam/caulk, with either foam board applied to the bottom of the floor as suggested earlier. Or insulweb or poly with dense pack celulose.
Check out the Demilec site and fill out the form for contractors certified to install their product in your area.
Feel free to e-mail me with other questions,
Garett
ps. Anything is better than FG especialy if it is in an open cavity. FG is better than nothing.
Is SEALECTIONTM 500 spray foam similar to Icynene ?? (fyi to AWB I think this may have been the product you saw
on 'This Old House' w/ Tom Silva)
. . I am considering Icynene but realize it probably easily 3x the price of fiberglass batts. After having reinsulated the attic in my previous house (memory escapes me but it was a big project, maybe 1200 sq ft), I am ready to contract out work in current house . . spending the saved hours doing something I like... . like scrounging and splitting wood
Thanks . .as this is an old thread I'll follow up with a PM
on 'This Old House' w/ Tom Silva)
. . I am considering Icynene but realize it probably easily 3x the price of fiberglass batts. After having reinsulated the attic in my previous house (memory escapes me but it was a big project, maybe 1200 sq ft), I am ready to contract out work in current house . . spending the saved hours doing something I like... . like scrounging and splitting wood
Thanks . .as this is an old thread I'll follow up with a PM
- Status
