Basement Wood Stove: Insulating Basement

[MTBSully]

Installed a nice Vermont Castings wood stove in my unfinished basement last fall. It seemed to help a bit, but not as much heat came upstairs as I would have liked. My guess is that this is mainly due to the large unfished concrete walls that are absorbing the heat. My plan for this fall is to insulate the walls so there is less heat loss.

I plan to use foam board insulation. Looking for tips and suggestions on materials/products to use. I've watched a few videos on how to do this and it seems pretty straight forward. Apply glue to the back of the board, and apply it to the wall up to the edge of the foundation. The joists currently have BAT insulation but i beleive there is foam behind them. I'll have to double check.

My basement wall for reference. it seems the best option is to insulate around the sewage pipes and fill in the cracks with expanding foam.


Appreciate any tips/suggestions from anyone who has completed this project.

 

[EbS-P]

Installed a nice Vermont Castings wood stove in my unfinished basement last fall. It seemed to help a bit, but not as much heat came upstairs as I would have liked. My guess is that this is mainly due to the large unfished concrete walls that are absorbing the heat. My plan for this fall is to insulate the walls so there is less heat loss.

I plan to use foam board insulation. Looking for tips and suggestions on materials/products to use. I've watched a few videos on how to do this and it seems pretty straight forward. Apply glue to the back of the board, and apply it to the wall up to the edge of the foundation. The joists currently have BAT insulation but i beleive there is foam behind them. I'll have to double check.

My basement wall for reference. it seems the best option is to insulate around the sewage pipes and fill in the cracks with expanding foam.
View attachment 300026

Appreciate any tips/suggestions from anyone who has completed this project.

Code says you can not have exposed foam insulation. That may or may not matter to you. Comfort board is allowed to be exposed. Do you have any plans to finished the basement in the future? Do you really want to heat the basin the winter?

 

[CenterTree]

Are the basement walls dry year round?

In order to cover over the foam boards on the walls, you could use furring strips (instead of gluing the foamboards). Then you will have something to nail/attach future drywall to. Tapcons for the furring into the concrete wall. Buy a decent hammer drill.

Plan for any wiring.

Also, include the top/horizontal part of your sill plate when installing foam board. You can use the GreatStuff cans to seal that area with small sections of foam boards cut to fit. I believe the rim-joist area is one place where insulation is OK to not be covered with drywall. Someone can correct me if I am wrong.

Maybe just "box out" around those drain lines? Would be a pain to replace any of those with spray foam locking them in.

 

[stoveliker]

Boxing the drain lines outside of the insulation envelope - does that carry risks of freezing? (don't know how cold you get there).

Foam in Joist bays should still be covered with drywall (or other noncombustible). It's important to insulate those well, as that'll otherwise be by far the coldest part of your basement outside structure, leading to condensation and rot.

 

[BrownT10]

I recently did a section of my exposed concrete walls. I glued foam board to the wall and then went over it with gypsum board. I put tapcon screws into the wall, pretty easy with a good hammer drill. I did this in a part of the basement that will never be finished. I will slowly do more area in the vicinity of the stove to reduce heat loss out the exposed walls.

 

[tlc1976]

Could it be that there isn’t enough air exchange to get the heat to the upper floor reliably? I know usually it’s against fire code to cut openings in the floor, but maybe some fans at the stairway to push the cold air down and get the heat to rise?

 

[CenterTree]

Some houses can be hard to get heat to rise from a basement install. Sometimes the most you can get is a nice warm upper level floor.

Our basement install heats the basement good, but little travels upstairs. Those concrete walls are a culprit too.

NOTE: Not sure of YOUR situation, but if you have forced air heat, make sure you do not have any return air ducts near your wood stove.

 

[hockeypuck]

heating from an uninsulated basement is alot of wasted heat. You could put a wood furnace in and run some duct work to certain points in the house. If you are not planning on finishing the basement or it has some water issues, might be the better bet. You just have to insulate the ducts.

 

[MTBSully]

Basement is dry year round. I had wanted to install the wood stove on the first floor, but there is simply no good area to put it with the current layout of my house.

I did install one vent in the floor above the wood stove, and left the basement door open which helped a little, but not much. I do not have forced hot air. Baseboard heat. The walls in the basement would become quite warm after hours of burning, which tells me they are a major culprit in stealing my heat, which is to be expected.

I will eventually be finishing the basement as time/funds permit, but for now id like to at least insulate to allow more heat to travel upstairs. For now I will temporarily finish the area behind and near the stove with fire rated concrete board. The rest I will finish out with Dupont Formular unless anyone has any other suggestions.

 

[stoveliker]

Be careful with the floor vent: you just made a hole in a fire barrier. It'll help spread the heat, but also CO, smoke, and fire. Best is to put a fire damper in there.

I have a vent too, from the basement stove area to the living room. Metal boot, metal duct, fire damper, then flexible duct down to the floor of the basement, an inline fan, and another vent register. The fan sucks the coldest air from my living room floor and deposits it on the basement floor. This pushes the warmest air near the ceiling of the basement up the stairs onto the main floor.

 

[MTBSully]

Be careful with the floor vent: you just made a hole in a fire barrier. It'll help spread the heat, but also CO, smoke, and fire. Best is to put a fire damper in there.

I have a vent too, from the basement stove area to the living room. Metal boot, metal duct, fire damper, then flexible duct down to the floor of the basement, an inline fan, and another vent register. The fan sucks the coldest air from my living room floor and deposits it on the basement floor. This pushes the warmest air near the ceiling of the basement up the stairs onto the main floor.

I had that concern when I added the floor register, it does have a damper built in. Any pictures of your setup?

 

[stoveliker]

I had that concern when I added the floor register, it does have a damper built in. Any pictures of your setup?

Unfortunately not. It's covered up.

But what I did is a boot, then 6" duct between the joists to a side wall, there an elbow followed by a fire damper. That means that from the damper at the side wall right below the elbow up to the LR register, all is metal. I.e. the damper is the "entrance" to the metal system.
From the damper down, flexible duct, then the inline fan (on a stand anchored to the concrete basement floor), then 4" more flexible duct to a boot and register in the chase I built. The flexible duct, and fan-mount only to the concrete is to minimize any vibrations from being transmitted to the floor (joists) of the living room.

 

[walhondingnashua]

I know materials aren't cheap right now, but I finished and insulated the one exposed wall I have in the basement. After some trial and error, just building a stud wall , leaving a gap behind the insulation (for some air flow on the concrete, using r13, and dry-walling over that was cheaper and turned out much nicer. Very happy with it.

 

[jimmyb]

Unfortunately not. It's covered up.

But what I did is a boot, then 6" duct between the joists to a side wall, there an elbow followed by a fire damper. That means that from the damper at the side wall right below the elbow up to the LR register, all is metal. I.e. the damper is the "entrance" to the metal system.
From the damper down, flexible duct, then the inline fan (on a stand anchored to the concrete basement floor), then 4" more flexible duct to a boot and register in the chase I built. The flexible duct, and fan-mount only to the concrete is to minimize any vibrations from being transmitted to the floor (joists) of the living room.

@stoveliker - very cool. I'm planning on copying your approach. My stove is in the middle of my basement and I'll be cutting two holes in the 1st floor on opposite ends of the house to install a 10"x4" boot in each with a fire damper, and then 6" flex duct to the floor registers in the basement. With the exception of the boot that will be in the joist bay, all of the duct and damper set up is going to be hung off the basement side of 5/8" sheetrock. Curious to know what type of fire damper you used and how it was installed? Was is a True Round or a square housing with 6" duct connection? I've read up some, and it seems like the code-compliant install of a fire damper requires it to be integrated into the framing, which I'll struggle to achieve. Any advice would be great. thanks!

 

[zrock]

I would have fired that plumber for running the popes the way they did down the wall... Personally if it was me i would frame in the walls and spray foam them this way you can get insulation around those pipes and hide them at the same time. Also with framing out the walls you will be able to rough in some electrical outlets that i do not see any, in the end this will increase value.. I would not secure anything to the wall with tap cons or any other type of concrete screw as concrete does get some moisture in it and that will transfer to the screws over time and then into your wall board.

To help move the hot air put a booster fan in the vent that you installed in the floor it will help create some circulation..