Insulation help

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faultymechanics

Burning Hunk
Oct 15, 2020
200
New Hampshire
Hey all,

My daughters room is significantly colder than other rooms in the house, especially upstairs. She is surrounded by exterior kneewalls at land directly over an open porch.

I climbed inside the wall today expecting to see zero insulation and discovered that fiberglass and rigid foam was there.

It appears the foam was nailed together and never sealed up tightly. I dont know the condition or installation quality of the fiberglass but I'm just trying to figure out what is the best move to improve her rooms temperature.

Do I lay another layer of foam over the current setup(foil facing this time, if you notice none of the current stuff is foil facing, yikes)?

Do I rip out everything there and get r15 rockwool and new foil faced foam(my original plan before I found out it was insulated)?

Videos of the space linked below:

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So the floor of the room is over an open porch? If so, is the floor insulated? As for the plastic film, that should be on the inside before the fiberglass insulation. Doubt the room is very air tight the way it is insulated now.
 
So the floor of the room is over an open porch? If so, is the floor insulated? As for the plastic film, that should be on the inside before the fiberglass insulation. Doubt the room is very air tight the way it is insulated now.
If by "floor of room" you mean the actual conditioned part of the room my daughter is in, it is not insulated as it is over our living room. Attached to her room is an inaccessible kneewall that is over the outdoor porch. That floor is not insulated.

The only thing insulated within the kneewall cavity are the walls against my daughters room(which was seen in my terribly shaking and nausea inducing video).

I'll put the photo below of a crude drawing explaining the setup from a 2d perspective.

[Hearth.com] Insulation help
 
I vote start over. Clear it all out. Air seal with canned foam. Then batt insulation. None of my attic has vapor barrier. I would probably just use 2” polystyrene glued to the studs. Tape the seams. Focus sealing the stryro to the top and bottom of the knee wall
 
I vote start over. Clear it all out. Air seal with canned foam. Then batt insulation. None of my attic has vapor barrier. I would probably just use 2” polystyrene glued to the studs. Tape the seams. Focus sealing the stryro to the top and bottom of the knee wall
Kinda where I'm thinking, and I'm planning to use rockwool.

i'm wondering, could I flip flop your order. Could I do the rockwool and then construction adhesive(or screw I guess) rigid foam across the studs and then tape the rigid foam seals and spray foam the bottoms and tops shut, or something to that effect?

Would it make any sense to take the fiberglass batts that I remove and put them on the floor over the porch ceiling? I am hesitant to do anything like that because I don't want to make a warmer space vs outside the roof and create condensation.

Hope is to get whatever the job is, done on Sunday.
 
i'm wondering, could I flip flop your order. Could I do the rockwool and then construction adhesive(or screw I guess)
The thinking goes air sealing as close to the conditioned space as possible keeps the warm humid air from escaping cooling and condensing in some unventilated space. If you do a decent job from then attic space and then seal all wall/ceiling penetrations from the inside as well, a vapor barrier in the attic just traps moisture between the paint of the room wall and the barrier. Exactly where you don’t want it. I would not rely on plastic sheeting to air seal. The wall. My 2 cents. If you were concerned I could make and argument that you should use 1” vapor barrier pink board that is cut to fit tight between the studs. Barrier to the house then seal all edges with foam to the studs then ad batt insulation. That is how you do rim joists. It’s a pain if it was not built to consistent dimensions. I would be equally concerned with insulation and air above the the ceiling of that room too.

Fiberglass is fine IMO.
 
The thinking goes air sealing as close to the conditioned space as possible keeps the warm humid air from escaping cooling and condensing in some unventilated space. If you do a decent job from then attic space and then seal all wall/ceiling penetrations from the inside as well, a vapor barrier in the attic just traps moisture between the paint of the room wall and the barrier. Exactly where you don’t want it. I would not rely on plastic sheeting to air seal. The wall. My 2 cents. If you were concerned I could make and argument that you should use 1” vapor barrier pink board that is cut to fit tight between the studs. Barrier to the house then seal all edges with foam to the studs then ad batt insulation. That is how you do rim joists. It’s a pain if it was not built to consistent dimensions. I would be equally concerned with insulation and air above the the ceiling of that room too.

Fiberglass is fine IMO.
So if I'm understanding you correctly. My options really are, batts between studs and nothing else, or rigid foam and spray foam between studs and then batts. Any concern about thermal bridging between studs if I go either of those routes.

Plan was for rockwool because we live right next to a main road.

Really appreciate your input and insight.
 
My options really are, batts between studs and nothing else
No, either batts or foam between, then you could add styrofoam over the top. The styrofoam (the white little beads) boards are vapor permeating if they don’t have the barrier. It definitely would help with bridging.

How is the room heated?
 
No, either batts or foam between, then you could add styrofoam over the top. The styrofoam (the white little beads) boards are vapor permeating if they don’t have the barrier. It definitely would help with bridging.

How is the room heated?
Oh you mean actual styrofoam, not rigid foam insulation over the top?

Room is heated via forced hot water through a single baseboard heater about 6ft long. we have a pellet boiler to heat that. The rest of the upstairs is plenty warm but her room is significantly colder. We use a sensor in her room to base the thermostat temp and it ends up boiling the other rooms and launching our heating bill to the moon.
 
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This is how our house is constructed. Are the exterior side walls of the room insulated? How about the ceiling? It looks like this should suffice as long as the other walls and ceiling are insulated. When we move into our house, none of this was insulated at all!

What is the heat source in the bedroom? Is this with ducted forced air heat or hydroponic heated baseboard? It might just be insufficient to make up for the heat loss of the room.
 
This is how our house is constructed. Are the exterior side walls of the room insulated? How about the ceiling? It looks like this should suffice as long as the other walls and ceiling are insulated. When we move into our house, none of this was insulated at all!

What is the heat source in the bedroom? Is this with ducted forced air heat or hydroponic heated baseboard? It might just be insufficient to make up for the heat loss of the room.
As far as I know, all the exterior side walls of the room are insulated similarly to the video.

Hydroponic baseboard. Ive definitely wondered if it needs more baseboard in the space but thats $$ and very intrusive of a job to complete on a sealed and finished house.

The other aspect is there is another similarly sized guest room upstairs with the same sized baseboard and it cooks in that room.

I suppose i could also double up the rigid foam.
 
If you can rent or borrow a FLiR to examine heat loss in the room, that would help.
How many sq ft is the room, how tall is the ceiling, and what is the length of the baseboard?

If the heat in is not adequate, then increasing the heat output is sometimes the better option. The baseboard heat could be changed over to panels for higher output in the same space. Runtel and Buderus makes them.
 
If you can rent or borrow a FLiR to examine heat loss in the room, that would help.
How many sq ft is the room, how tall is the ceiling, and what is the length of the baseboard?

If the heat in is not adequate, then increasing the heat output is sometimes the better option. The baseboard heat could be changed over to panels for higher output in the same space. Runtel and Buderus makes them.
So I have an approximate square footage from when we had the wood floors refinished. Was about 120sqft. Ceiling is about 10ft but knee walls make that inconsistent throughout.

The closet in her room with the door closed becomes an ice box.

Baseboard is probably 6ft long. I can triple check when home.

So those panel heaters just make more efficient use of the hydro heating?
 
So I crawled inside and pulled some of the rigid foam back. It does seem like they did a decent job of putting in the fiberglass, nothing dropping.

That being said, from what I'm reading and what has been said here, they should have put the rigid foam on the inside against the interior wall, sealed it and then added the batts, is this correct?

If i buy new rigid foam to redo this, do we think the fiberglass batts can be reused? After reading more im certainly afraid of leaving it and continuing to trap moisture between the walls and the rigid foam.

Additionally there were some spots with blown in cellulose and I was wondering if it looked the way it did due to age, or from absorbing moisture? I live in Northern NH so it gets to subzero temps around here if that matters.

[Hearth.com] Insulation help


Also this rigid foam is non foil facing...has me concerned regarding fire safety since it appears someone did this insulating work with this foam in almost every knee wall upstairs.....

Also may be worth noting in the above photo, that is where the porch ceiling ends and it becomes a space above a conditioned area. Im assuming thats why there are batts between the rafters and blown in cellulose.
 
So I have an approximate square footage from when we had the wood floors refinished. Was about 120sqft. Ceiling is about 10ft but knee walls make that inconsistent throughout.

The closet in her room with the door closed becomes an ice box.

Baseboard is probably 6ft long. I can triple check when home.

So those panel heaters just make more efficient use of the hydro heating?
Basically, they increase the surface area for a higher per linear foot output. A 6' baseboard heater is fairly small, about 600 btus. A 20" x 48" Buderus panel puts out about 9 times as much heat. Sounds like a smaller one would work ok. One way to test would be to put a 500w heater in there for a bit and see how that works. That's about 1700 BTUs. If good then a much smaller panel will work. If not, try a 1000w heater. That would be equivalent to about a 12" x 48" Buderus panel.
 
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Basically, they increase the surface area for a higher per linear foot output. A 6' baseboard heater is fairly small, about 600 btus. A 20" x 48" Buderus panel puts out about 9 times as much heat. Sounds like a smaller one would work ok. One way to test would be to put a 500w heater in there for a bit and see how that works. That's about 1700 BTUs. If good then a much smaller panel will work. If not, try a 1000w heater. That would be equivalent to about a 12" x 48" Buderus panel.
I did measure and it's 8' of baseboard.

Plan this weekend is to remove current insulation. Replace with r15 rockwool then cover across back with foil faced 1.5" r9 foam. Tape all seams and spray foam any openings above, below or around any irregularities.

Ill test the temp over the week and if it's still colder ill look into those radiators for her room.

Fingers crossed improving the airseal and going from (at best) r16 to r24 will make a difference.