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Improving the insulation in an attic room

I have a raised dormer divided into 2 rooms. The larger of the 2 I'm trying to insulate better. It should be noted it has no heat as in forced air. There were some baseboard heaters but I removed them after a bad ice dam. I'd like to avoid electrical heating because of cost.

The room is about 25'x15'. Ceiling going from 6' to about 9'. There are a few nooks and crannies.

The back part of the attic is quite cold even during this relatively mild winter. As far as insulation it has some in the back walls, wall on front of house(both in 2x4 construction)Very large sky light which I know is a problem too. Temporarily I stuffed it up with r-30 and taped it off but it didn't seem to help any.

I'm by no means an expert on insulation. However I don't think the lack of generated heat is the only problem.

What i'm trying to determine is if I could do a better job at making the room warmer? I have to think the back wall with the rest of the attic and all it's cold is the big problem. Would it help any if I added more stud framing and doubled up on the insulation. I'm talking about going so far as 2x6 framing with r-30.

There is also an entrance to the attic through a back closet. I filled the cavity up with r-30 but it didn't really help.

I'm in SE Massachusetts. Records aside our lows can be around 0 degrees or a few below. The room can be extremely unbearable when it drops below freezing outside. In the summer it's just the opposite. The room can feel like an oven in the high 90's.

Is it even worth the fight? Or are attics impossible without a lot of heating? I'm just trying to get the room comfortable or manageable. I may isolate the room more from the other and the stair well but I really wish to keep the size. primary use will be as a recording studio. Guitarist don't like cold hands.

Re: Improving the insulation in an attic room

I'm having trouble visualizing the room, but before you start heating the room, make sure that the roof will not warm up and create ice dams. Make sure the underside of the roof is well vented.

Make sure you have plenty of insulation on top of the ceiling, r30 or more. For any slanted walls that are the underside of the roof, remove the sheetrock, Check the insulation that it has 2" of space between the top of the insulation and the underside of the roof for airflow. Staple the flanges to the edges of the rafters, not the sides. The cover the rafters with 2" rigid foam boards. This will sharply reduce the heat loss through the rafters and keep the roof colder.

For all the side walls, remove the sheetrock and use 1" or 2" foam boards on them. Regular r11 wall batts with 1" foam should be enough. Weatherstrip all windows and any doors that exit to a cold space. With all this, you should be able to heat the room with a 1500 watt electric heater, and you will only need to turn it on when you are using the studio.

Re: Improving the insulation in an attic room

I'm pretty sure there is venting in the ceiling going through each channel. You can see them in the attic. So I don't think I'll be taking all the sheet rock off. I can peak in and see if they used the right kind of insulation.

Adding foam sounds good but you still need to add some sheet rock or sound board or something. Foam wouldn't sound too good. You also need a solid mass. I'm just talking about sound reflection.

The roof was treated with some rubber like stuff and haven't had an ice dam since.

I sure hope the right kind of insulation was used in the roof. It would explain a lot of things if I found r-9 in there. Always said it was 50 degrees on the thermometer. I did the sheet rocking on the front face. It definitely made the room warmer.

Thanks for your advice. Think I'll look into that foam. I'm also looking to treat the floor with some special foam which might help as well. The stuff weighs 2 lbs per sq foot. Fiendishly expensive but blocks 85% of sound. I figure it'll insulate as well. I'm also thinking of summer with heat rising and a room that can get hot enough to prevent my computer from working.

Re: Improving the insulation in an attic room

I did mean to sheetrock over the foam. They make longer sheetrock screws for this, up to 2" longer I believe, so that limits the total thickness of the foam to 2". I suggested the rigid foam sheets as an alternative to furring out the studs for cost and efficiency. I wouldn't use it on the ceiling though as it is cheaper to add insulation over the top of the joists.

You want to cover the tops of the joists though to cut losses from the conduction of the wood. The wood has a lower R value than the insulation and makes up about 10% of the total ceiling area. The loss through the wood is greater than the 10% due to lateral conduction by the sheetrock on the ceiling. It conducts heat around the insulation. Cover the joists with insulation and you break this path.

That is also the reason for using a foam board between the wall studs and the sheetrock. Same under the slanted part of the wall/roof.

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