Hot/Cold air vents/returns

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emory

Member
Hearth Supporter
May 30, 2007
56
Milton, NH
Fired up the wood stove for the first time the last couple nights and I'm so happy that all the work to get this running has paid off. The stove runs great and heats up the basement quite quickly, went from 55-70 degrees in less than a hour. The only problem now is that the air is not flowing to the upstairs, even though the staircase is open with no door. Tried using a window fan on the ceiling to blow air up the staircase as a temporary solution but that didn't really do anything. Basically the upstairs stayed relatively unchanged all night, around 62-64, and the basement cooked, 75+.

I had a feeling this would be the case, the previous homeowners stated that they heated the entire house from the basement. However, the stove they had, VC Vigilant, was totally junk and there was no way it worked efficiently enough. Add on the fact that there are no cold air returns anywhere on the main floor.

The house is a newer, well insulated Ranch. The stove is located in the basement.

Is there a way to calculate the best place for air vents/returns so that I can get a good convection current flowing?

I've attached a diagram of the floor layout and specified where I was thinking of putting the vents.

The main vent would be in the kitchen area, underneith the sink where the kickboard is with a 90 degree vent. This would be slighly off centered from where the stove is below.

Then have two return vents in the guest and master bedroom.

Any opinions/feedback would be grealy appreciated before I start cutting holes in the floor. :)
 

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My guess would be the vents in the two bedrooms would bring the cold air down and force the hot air up the stairs. Maybe a small fan in those vents would also help. But this is just a guess, all houses act differently and it can be real tricky getting the heat up from a basement.

If you plan on cutting floor vents look into fusible fire safety vents that will close automatically in case of fire, and make sure you have smoke/carbon detectors.
 
Hi Emory,

Sorry to hear you predicament. Please do a search on this forum for air vents, returns, cutting holes, stove in basement, etc. A lot has been written about that in the past and that is still really useful information

You will see that heating a house with a stove in the basement is almost impossible. Very few people get that to work. Then, most ask the exact question you did (cut registers in the floor) and the response is :DONT DO IT. Firstly, as the inspector will say, it is illegal for fire hazards sake. Secondly, it really does not help. Some people tried running their forced air fan, others cut holes (illegal) and saw no improvement, etc.

I have a similar house with similar features and the only thing that has helped is to have a fan that blows the air from the stove room to the house. It is a vornado. I mounted it above the stove and directed it to the stairs. That should work in your case too. And that is all you are allowed to do legally. Another fan in the living room blowing towards the kitchen/hallway might help too.

Don't be discouraged. It took me 5 years playing with fans to get the optimal air distribution, so it will take you some time too.

Carpniels
 
I have a little 75 CFM fan on the door jam blowing the warm air up. What that actually does is induce the cold air to flow down the stairs. I have a split level so it is really only have a flight of stairs. It is really more about getting air to circulate than it is to provide multiple pathways for heat...I think...
 
carpniels said:
Hi Emory,

Sorry to hear you predicament. Please do a search on this forum for air vents, returns, cutting holes, stove in basement, etc. A lot has been written about that in the past and that is still really useful information

Thanks, I've done a bunch of searching and read a ton of threads before posting. Reason I presented my scenario is they all seem to digress into either:
A) It's impossible
B) You're gonna kill your whole family with CO2
C) You're gonna burn your house down

I've lived in two other homes previously with a wood stove in the basement that worked fine. My current home has many decent size holes in the floor for plumbing to the kitchen and bathroom so I fail to see how others will result in an even more accelerated fire.

I've got CO2/Smoke detectors and I plan on putting fire safe vents in.

I was just surprised, with such a large open staircase into the living room how the heat was contained to the basement so well....
 
It's not impossible to heat your home from a basement and not illegal to cut holes in your floor to help circulate air. If it is illegal I have yet to see the law stating it. I've done it in 3 different houses and it worked every time. It works better in smaller homes that have open floor plans and centrally located stoves and stairwells. You can't be greedy and expect the upstairs to be the same temp as the downstairs, your going to have a difference of 5-10 degrees. And yes it's a good idea to have smoke/carbon detectors whether you cut holes or not, and make sure you have a properly installed stove.
 
My current home has many decent size holes in the floor for plumbing to the kitchen and bathroom so I fail to see how others will result in an even more accelerated fire.

My suggestion to you is the draft stop all those hole you see..

It’s not impossible to heat your home from a basement and not illegal to cut holes in your floor to help circulate air. If it is illegal I have yet to see the law stating it

Then I guess your inspector was ok with it or you never bothered to pull a permit to do so How are you going to find codes if you never looked


Today all purges pipes wires ect have to be drafts stopped and or fire blocked. One is not supposed to cut into natural containment structures.

Even worse the ones that advocate it urging and encouraging others to f0llow their misguided non permitted actions.

Is it any wonder my insurance goes up because of actions or others misguided disregard foe safety.

The best way to get heat out of a basement is not to install the stove there in the first place. Install the stove in the space that requires the heat.

Unfortunately fueable link dampers do not restrict the flow of Carbon monoxide the last place I would want to increase that risk is in a bedroom when I sleeping.

Does none need code to apply common sense?

Where is the lowest negative pressure zone in a home? ( the basement) Why would anyone install a stove there in the first place? Just think how much better it would opperate when taken out of that negative zone. For that matter, heating w equipment should not be installed in un conditioned areas According To Hud and Energy star homes.. So now they are mechanically removing air from a negatively challenged area to begin with. Think about that for a moment?

I repeat some will disregard safety to move heat Its there life their home , But I take exception to them advocating to others to follow these unsafe dangerous practices.

Really if they were smart,they would keep to themselves And not broadcast to the world that maybe the are not so smart at all.
 
elkimmeg said:
My current home has many decent size holes in the floor for plumbing to the kitchen and bathroom so I fail to see how others will result in an even more accelerated fire.

My suggestion to you is the draft stop all those hole you see..

It’s not impossible to heat your home from a basement and not illegal to cut holes in your floor to help circulate air. If it is illegal I have yet to see the law stating it

Then I guess your inspector was ok with it or you never bothered to pull a permit to do so How are you going to find codes if you never looked


Today all purges pipes wires ect have to be drafts stopped and or fire blocked. One is not supposed to cut into natural containment structures.

Even worse the ones that advocate it urging and encouraging others to f0llow their misguided non permitted actions.

Is it any wonder my insurance goes up because of actions or others misguided disregard foe safety.

The best way to get heat out of a basement is not to install the stove there in the first place. Install the stove in the space that requires the heat.

Unfortunately fueable link dampers do not restrict the flow of Carbon monoxide the last place I would want to increase that risk is in a bedroom when I sleeping.

Does none need code to apply common sense?

Where is the lowest negative pressure zone in a home? ( the basement) Why would anyone install a stove there in the first place? Just think how much better it would opperate when taken out of that negative zone. For that matter, heating w equipment should not be installed in un conditioned areas According To Hud and Energy star homes.. So now they are mechanically removing air from a negatively challenged area to begin with. Think about that for a moment?

I repeat some will disregard safety to move heat Its there life their home , But I take exception to them advocating to others to follow these unsafe dangerous practices.

Really if they were smart,they would keep to themselves And not broadcast to the world that maybe the are not so smart at all.

I knew you would bash me on this. That's ok, opinions are like azzholes, everybody has one. How is this such an unsafe dangerous practice? Just because I have a floor vent doesn't mean I'm going to die from it. Burning wood is a risk all by itself. Hell, life is a risk. If I had a fire it's more likely to spread up the open stairwell than a little floor vent. If your so worried about carbon monoxide, fire and smoke then don't burn wood period! A properly installed woodstove, and maintained smoke/carbon detectors will give you the warning you need in case something were to happen.

Actually I have looked for the code and laws and found nothing. Also asked stove shops and even a local inspector, they all say it's ok. I've asked you this before, if you can reference the code number I'll look it up. Last time we beat this horse you referenced a code that had nothing to do with this subject.
 
Actually I have looked for the code and laws and found nothing. Also asked stove shops and even a local inspector, they all say it’s ok.

Since you have looked at every code them would you mind posting the language in one and two family dwellings concerning draft stopping and fire blocking openings.

In real life If I fail an inspection the onus is on the installer to provide codes or documentation that supports their installation
U you mind tipping over your cards and tell us all haw safe the practice is your are advocating backed by code language and not hearsay from installers that can't find their big toe from their elbow After you produce the draft stopping code I will b provide the official International code cometary discussing the topic
 
Why don't you just save me the time Elk, and show me where it says "one shall not cut holes in floor to install vents to circulate air" Trying to interpet these codes just gives me a headache.
 
My woodstove is in the basement and it actually works pretty well for us. We have a 2000 sq foot two story house built in 2003 that is well insulated (including basement insulation). The stove, a huge, ancient Fisher clone, is centrally located in the basement with two cold air returns from the first floor and an open airway up the stairs to the first floor. No vents or other holes in the floor. The returns are two baseboard registers near the center of the house with ducts that go down to about an inch or two of the cellar floor. I installed the old stove last winter as a test because everything I'd read on this board and others told me it wouldn't work. However, when the stove was going the house was a comfortable 68 degrees on the first floor and 65 or so on the second (which I actually prefer for sleeping purposes), no matter how cold it was outside. On warmer days and in the Spring I'd fire the stove up in the morning and that would be sufficient. Through the cold days (and it can get very cold in Central NY) we kept the fire going 24/7 and that kept us warm.
I have to say that I think the main form of heat generated in this system was not convection (warm air circulating through the house) but radiant heat coming from the floor and other parts of the house that were heated by this method. I say this only because of what I feel by walking around the house, not by any real testing. When I look for air currents I can see that the flame from a lit match will bend over at the outlet of one of the air returns, but only rarely from the other and that I can feel some air flow in the stairway but neither seems like a huge volume of air. However, when you can feel that the flooring on the first floor is as warm as when the OHW radiant heating system is turned on.
At some point we plan to get a wood fired boiler to tie into the radiant system, but presently I think it will be more cost-effective to upgrade the stove to something a little more effcient than the Fisher.
 
R602.8 Fireblocking required. Fireblocking shall be provided
to cut off all concealed draft openings (both vertical and horizontal)
and to form an effective fire barrier between stories, and
between a top story and the roof space. Fireblocking shall be
provided inwood-frame construction in the following locations.
1. In concealed spaces of stud walls and partitions, including
furred spaces and parallel rows of studs or staggered
studs; as follows:
1.. Vertically at the ceiling and floor levels.
2. At all interconnections between concealed vertical and
horizontal spaces such as occur at soffits, drop ceilings
and cove ceilings.
3. In concealed spaces between stair stringers at the top and
bottom of the run. Enclosed spaces under stairs shall
comply with Section R311.2.2.
4. At openings around vents, pipes, ducts, cables and wires
at ceiling and floor level, with an approved material to
resist the free passage of flame and products of combustion.
5. For the fireblocking of chimneys and fireplaces, see Section
R1003.19.


2.3. Return-air inlets shall not be located
within 10 feet (3048 mm) of any appliance
firebox or draft hood in the same
room or space.
3. Rooms or spaces containing solid-fuel burning
appliances, provided that return-air inlets are
located not less than 10 feet (3048 mm) from
the firebox of such appliances.


M1801.5 Mechanical draft systems. A mechanical draft system
shall be used only with appliances listed and labeled for
such use.

M1801.9 Fireblocking. Vent and chimney installations shall
be fireblocked in accordance with Section R602.8.
M1801.10 Unused openings. Unused openings in any venting
system shall be closed or capped.

3. Connectors serving appliances operating under a natural
draft shall not be connected to any portion of a mechanical
draft system operating under positive pressure.

3302.2 Penetrations of fire-resistance-rated assemblies.
Installations in hollow spaces, vertical shafts and
ventilation or air-handling ducts shall be made so that the possible
spread of fire or products of combustion will not be substantially
increased. l penetrations through
fire-resistance-ratedwalls, partitions, floors or ceilings shall be
protected by approved methods to maintain the fire-resistance
rating of the element penetrated.
 
elkimmeg said:
3302.2 Penetrations of fire-resistance-rated assemblies.
Installations in hollow spaces, vertical shafts and
ventilation or air-handling ducts shall be made so that the possible
spread of fire or products of combustion will not be substantially
increased. l penetrations through
fire-resistance-ratedwalls, partitions, floors or ceilings shall be
protected by approved methods to maintain the fire-resistance
rating of the element penetrated.

90% is totally irrelevant since the user is not fabricating a concealed draft chamber; nor are they affecting direct connections of combustion air and return air feeding the appliance.

The above paragraph is the only one that comes close to saying what you're saying, assuming you are penetrating a floor rated for fire resistance, and assuming this is not out-of-context. Not sure my first floor could be considered rated for fire-resistance - as far as I know, it's all completely combustible - no drywall on the ceiling in the basement. Not like the case of a wall and fire-resistant door between house and garage, for example.

Even if you accept that a bottom floor is built to a fire-resistance specification, it's far from clear that the "substantially increased" term does not allow it - all open to interpretation. If someone installs a floor grate with a heat-fusible link to close a damper, or a smoke alarm triggered normally-closed damper to close, I see no issue with it.

-Colin
 
It is quite convient to dispute presented documentation, when you supply none to the contrary

In order for it to be a fair debate ,I would expect you have codes. statistical studies,or recognized data, to prove compromising

containment barriers make one safer in their homes. At this point I get to equally analyze what you present
 
Elk, how does code deal with split levels? How about large openings like stairwells connecting floors that have no doors? Seriously, this is how our house is setup.

This is such a frequent topic that it would be really helpful to know the actual code(s) covering penetrations between floors. I have been an advocate for fire-dampers in any between floor penetrations, but this comes more from experience in commercial applications. I'd like to know that this is residential code compliant. Is it?
 
elkimmeg said:
It is quite convient to dispute presented documentation, when you supply none to the contrary

In order for it to be a fair debate ,I would expect you have codes. statistical studies,or recognized data, to prove compromising

containment barriers make one safer in their homes. At this point I get to equally analyze what you present

You're not presenting documentation that is relevant. As Todd and others have said - if you're going to be so adamant about this point and scare people that they're somehow violating things, you need to show the code that clearly says in context of this application that you cannot cut holes in floors and install registers/returns in a house. Otherwise, you need to leave it at "my personal feeling is..." and not "code says..."

Code about direct connections to flues/air supplies of combustion appliances aren't at all relevant to this case.

-Colin
 
Bad attempt to dodge thee issue of are you safer with the holes cut through natural containment structures?

That is the question plain and simple, either you have valid argument or you do not

I can tell you studies prove containment saves lives and afford valuable exit time I don't need codee to present common sense and documented studies


http://www.fireengineering.com/articles/article_display.html?id=196217

Over the past 30 years, the three national model building codes have called for increased use of sprinklers while steadily rolling back requirements for fire-resistant components such as walls, floors beams, trusses, girders, dampers, doors, cables and columns, concrete, fireproofing, fire duct wrap, firestop systems, fire rated glazing, and fire rated wall and ceiling boards. These components and materials help control the spread of fire, limit the damage to a burning building and surrounding structures, and allow sufficient time for occupants to escape and firefighters to do their work before the structure collapses.
 
That's an interesting read, thanks for the link. The article seems to be much more towards commercial installation and doesn't answer the question. What is the residential code regarding penetrations between floors, specifically for floor vents?

The article does bring up a good point, but left me wanting to know - Why are there so many more fire related deaths in the US as compared to Europe and other industrialized nations? Is it fire containment, sprinklers, better construction techniques, better regulations and enforcement or just better common sense? What are they doing differently?
 
elkimmeg said:
I can tell you studies prove containment saves lives and afford valuable exit time I don't need codee to present common sense and documented studies

The safest house is one that has no heating system and no electrical system that could ever fail. But I don't think most of us are going back to rustic cabins and sleeping bags.

What you're really saying in all of this is that there is no clear residential code and you're going on your own opinion. That's fine and we're all entitled to that - but please don't try to scare people that they're in violation of "code" that you cannot produce.

-Colin
 
LEt me ask the question again are people safer with holes cut into natural containment' structures and If so please provide supporting information;

Many complain there are too many codes at this point the same are complaining I have not yet provided enough Do we really need a code for common sense? there is not code to tell you not to stick your finger in a light socket but common sense should tell you not to do so By the time I done I can provide enough evidence that your safety is reduced by eliminating natural containment in your home. Code also provides if removing part of a structure that alike member must be replaced and that it restores the original structure or integrity of what was removed

during rough frame inspections my job is not only to determine whether the structure meets code but also to inspect fire blocking draft stopping to prevent verticle movement and containment of potential fires. IF I do my job correctly, the people living in that home can sleep easier But here on hearth.com members want want to cut holes in natural containment structures and negate all diligence I have done. Perhaps they could shed some light to help me understand why I should look the other way when it comes to containment. Perhaps they should petition and suggest Fire stopping and draft stopping not be part of the residential code. I all for making my job easier. Hell I would never again have to check ASTM E -136 standards because who b gives a -----

I'm sitting in the fire academy in Marbrough ma watching films or how fires spread and having the film stop with a time lapsed registered on the screen watching just how fast these very purges should have been inspected and split c screen the difference of the correct fire stopping and draft stopping I saw what is being studied and researched with my own eyes.

Let me clue you seconds saves lives naturally NY soapstone can provide contrary imfo. as I asked numerous times yet he avoids the question time and time again. If he is so sure than educate me an all of us containment seconds do not save lives. NY I man enough to admit mistakes and when I wrong then learn form it and move on Tell of the forum members they do not increase any risk orr safety tell them containment is over rated tell them valuable seconds mean nothing Continue advocation safety reductiion.
 
OK, so the short answer is there is no residential code dealing with this type of vent. Correct? And for the hundreds of thousands of homes in the US that have open staircases, lofts, etc. they are in violation of all common sense and reason. Fair enough.

Oh well, my wife is not going to like the open staircase being boarded up at all.
 
Stairways were the first component's in homes to be required smoke detector coverage. Now also vital positioning of Carbon Monoxide protection.. As studies s expanded smoke detector coverage was expanded to bedrooms. Every home changing hands in this state must have both Smoke and CO coverage tested and inspected by the fire dept The reason for coverage is stairways are natural convection paths. But BE green if you want to feel safer by all means boarding them up will add to the protecction.

but use the right material here is a did you know that ceiling just cut into the 1/2" gysum provides 30 minute containment protection. In fact that gypsum is also one of the approved materials for fire blocking that 3/4" plywood is also an approved material for fire blocking this code. I will cut and past later when I fire up the lap top to back up that info.

That's right the very material cut to make holes,, are vital components of the natural containment structures.


So I'll ask of you BEgreen to provide info where safety is not compromised by cutting into natural containment structures?


Why is you ask me to provide info yet no one can answer that simple question to support the practice of cutting natural containment areas?

In life there are compromises , and for convince stairs are one. If I am interpreting what you are saying, because we have stairs it is ok to further decrease our safety?

That just like saying 15 wrongs makes ok for the 16th wrong. Again a very weak argument

I will continue to research for code language they might be within the volumes of our fire codes NFPA.
 
As you already know, there is likely noone that can provide support that people are safer with holes cut into their containment structures. Obviously, a house with holes in the floor will be safer--at least to a degree. How much of a degree is questionable. Is a house with passive vents in the floor unsafe? In terms of safety, is the difference significant? A person isn't "safer" burning a woodstove in their house, versus simply having a natural gas furnace. Further, I suppose one might also be able to argue that a house with a heat pump is safer than a house with a gas furnace. The same might be true for electric vs. gas hot water heaters. I think the issue comes down to the degree to which having holes in floors, or floor vents, make a house less safe? Is a house with floor vents substantially less safe than a house without them. That is, is there is a significant difference with regard to safety between these two scenarios when other safeguards are present (i.e., smoke/carbon monoxide detectors)? Does the amount of flame spread increase that much when a house has passive floor vents? It seems this issue is being made black and white, when it clearly cannot be categorized as safe vs. unsafe unless there are actual studies conducted.

elkimmeg said:
LEt me ask the question again are people safer with holes cut into natural containment' structures and If so please provide supporting information;
 
Elk, you're the code expert. I am asking you for the specific code so that when I recommend putting in a fusible link damper for an in between floors I can back it with some code. If this isn't covered in residential code, just say so instead of beating around the bush. No one is asking you to defend your personal opinion as long as you state it that way.

However, when there's a 10 x 12 foot stairway opening in the house, it becomes a moot point, especially when the opening is 100% code legal. Mine will remain open, (but I did change the batteries in the detectors last week, right on schedule).
 
there is code that states th penetrations holes in this case have to be isolated Meaning the rest of the concealed stud cavity cannot be left open it needs to be fireblocked. this is interpetations and I'm trying to be objective Another point I am referencing parts of the NFPA I never ventured in before because this issue is both a fire containment issue plus a building code issue.

Even penetrations in a floor un-rate floor assembly must maintain the original integrity A fusable link damper will provide protection further more according to the NFPA 92 it should be set 50 degrees over ambience and no more than 177 degrees Most are in the 130 to 140 degree range. Another issue is the degrees of the heat being transfered Floor joist return plemtums are allowed to only for return air less than 100 degrees. This gets a particularly tricky, in that engineered joist adhesives start melting around 170 degrees or so. once the glues start to melt there goes the structural integrity of the engineered joist. Common construction grade 2/ stock can withstand hundreds of degrees of heat.

the main issue I have,is if someone want to take it upon himself and reduce his home and family safety , then he suffers the consequences (Hopefully disaster never happen)
what I take issue is, advising, encouraging for others to follow this unsafe practice. I feel that at least someone, has to warn them that a price could be paid

I did not take all this effort, if I did not believe it worth all the factors being considered. Another factor is very little engineering is involved there a bit more to moving air then just cutting holes
Supply without returns is useless. Another factor is trying to heat in an unfinished basement located in the lowest negative pressure zone High pressure always gravitates to low pressure so
those floor vents have to overcome a pressure flow even before any warm air can pass threw. Another interesting issue is the cellar floor should be insulated no wonder it is cold above there over 15% of heat loss occurs due to the lack of proper insulation of either the floor or foundation Wood stoves are area heaters they belong in the space that requires the heat.

No more research tonight I split ans stacked more tha a cord today I think I will finally look at the other post and see If I can help someone that wants help
 
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