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Cape Attic Insulation

I have a two story Cape and the second floor is very cold even when heated. I have replaced the windows. There are two bedrooms with walls that back the easment(attic) on either side of the house. The walls are insulated from the attic with the paper on the insulation facing the attic and are covered with card board. Is this a problem? Should I replace this insulation and cover with plastic?


Re: Cape Attic Insulation

Here are a couple of photos of the upstairs in my place that is gutted for renovating.
They might be helpful for illustrating.

The reason it may be cold up there depends on how much insulation (R value) is placed in the walls ... in the ceiling ... and is there insulation in the floors separating the cold zone and the living space. Insulation should run from the cold area in the floor joist bays and past the under side of the wall into the room a few inches .... if there is no blocking there.

The paper faced insulation you currently have is actually installed backward. The paper backing is supposed to be a vapor barrier ( weak in my opinion) but it's supposed to be toward the warm (room) side of the wall. Whatever you do ... don't cover this insulation with plastic on the cold side. It would trap moisture inside the insulation severally degrading the performance of the insulation and could encourage mold.

Re: Cape Attic Insulation


If the wall insulation (faced fiberglass batts) is installed backwards (paper facing toward cold attic space).........then there's a good chance that the FG is getting damp/wet from condensed moisture accumulating from the warm side of the wall. This would/will substantially lower it's R-value.

Also, FG batts are not an effective air barrier. Air movement inside/thru the FG would also substantially lower its R-value. You likely need something more substantial than cardboard as an air barrier/wall covering on the attic side.

What comprises the ceiling in these bedrooms? Is the ceiling plane actually the bottom of the rafters........ or is there a flat horizontal portion of ceiling?

If the latter, what comprises this flat portion of ceiling? Drywall or ??? Have seen some less than stellar arrangements and materials used in attic spaces. Such as........ceiling comprised of 1/4" paneling and translucent light panels with hanging flourescent light fixtures mounted above. To top it off, a ridge vent was installed in the roof. The warm air from the house naturally leaked around the lighting panels and was sucked right out the ridge vent. The harder the wind blew, the more the suction. Sometimes the suction was so intense that it tossed the lighting panels onto the floor. :eek: His heating and cooling bills dropped over 50% once we corrected the disaster.

Is there insulation in the ceiling? What type and how thick? (If FG batts again....is the paper-facing toward attic or toward roof?)

Type of heat is? Is there adequate delivery of heat to this attic? (Might be impossible to determine until the attic is known to be properly sealed up and insulated)

Are the walls of the house balloon-framed? If so, are/were those stud bays blocked off at the attic floor with something other than the FG batts? (For now....particularly interested in the ones at the gable ends of the house because those are walls in the bedrooms, yes?)

Re: Cape Attic Insulation

goldhiller ... thanks for filling in the gaps with your post. ;) :)
I was pretty vague .... that's what happens when you try and do it in a hurry.:o

Re: Cape Attic Insulation

Should I put plywood or drywall on the attic side? What R value insulation should I use between the walls.

Re: Cape Attic Insulation

Depending on how old the insulation is that's in the walls .... the modern bats of insulation are higher density ... so for 2x4 walls they have approx. R15. Since heated air rises most heat loss is through the ceiling. So if you have an R15 in the walls it may be adequate .... though it doesn't hurt to put more there.

If the existing insulation is in good shape and not compressed , ratty , or damp with moisture you can use sheets of rigid foam to cover the insulation on the attic side. What this will do is add a thermo break to the wood studs which will prevent the cold transferring through to the room ... plus it will provide an increase to the overall insulation performance to the wall.

Hope this helps.:)

Re: Cape Attic Insulation

from the photo's, it looks like you have gutted the upstairs. Have the back side of the roof deck done with 5" of closed cell spray foam. I live in a city where the majority of the homes are cape cods and they all have ice hanging off their gutters.

The spray foam will kill the ice, and will make the upstairs much much much more comfortable, and you energy bill will be alot smaller.

Trust me. Foam is the way to go.

also have the gable ends foamed too!

Cape's are the darnest to heat and cool upstairs because of their design. If you can get a foam cap on your home, you will a much happier home owner now that you have it open.

7 out of 10 customers homes I visit are capes.... they su*k to insulate unless you have everything open like you do now. Do it right, and you will much better off when you get the walls closed and utilize the upstairs.

Closed cell foam is about R-7 per inch so in a 3" gable R21 can be hit, and in a 6" roof rafter R-35 can be done. The foam is more expensive, but you will be glad you did when your done. No more ice on the gutters, a comfy upstairs, and lower energy bill. The foam will pay for itself over and over again.

Re: Cape Attic Insulation

I have 4 gable windows on this Cape(2 on each side 1 front, 1 back) Do the gable vents on Capes need to be left completely open all year round or can I leave the windows open 2 inches to allow air to circulate through the attic? Should I place insulation on the outside wall since the windows are open?

Re: Cape Attic Insulation

best thing to do is give me a call, and email me some pic of your upstairs the more the better, and i can give you the best resolution to your issue. Cape Cod's are a pain to insulate unless they have the upstairs gutted. If you have that done, Spray foam the entire thing, roof, gables, etc. you will be happy that you did.


Re: Cape Attic Insulation

I've been reviewing the posts on insulation. Thanks for the great information.

I have a cape as well, but I'm not planning on gutting the attic area. The current insulation is fiberglass batt- some old some newer. It sounds like the closed cell foam is the way to go if they can do it from the enclosed attic space.

? How much space should they need to apply it?
? Can they insulate the outside ends of the space between the attic floor and the ceiling without damaging the ceiling? Sounds like it should go from the outside edge and extend to the kneewall?
? How thick does it need to be? Connecticut a mile or so in from the shore.
? Can you give me a rough idea of how much this should cost? (Connecticut)


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