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Prep for finished attic

We just purchased a cape with an unfinished attic. There is no ventilation. I would like to finish it and my idea is to put soffit vents into the knee wall area and then run baffle to the top behind the wall and ceiling insulation and install a gable vent on both ends of the house. Will this work?


Timothy Miller
Re: Prep for finished attic

Yes. If you live where there is wind blown snow you might install furnace filters on the inside of the gable vents so the snow does not blow into the attic. Also consider a ridge cap vent instead of the gables. One removes some ridge cap at the roof peak an cuts back the roof decking 1" on each side of the ridge then installs continuous ridge cap venting . This venting has built in insect/snow baffling. There is code issue for # vents per square foot of attic space the local code officials will tell you what it is.

Re: Prep for finished attic

Thanks Timothy,
Ridge cap would be a little pricey for me, since I would not do it myself, plus they just put a new roof on the year before we bought it. Glad to here the other way would work.
Thanks again

Timothy Miller
Re: Prep for finished attic

Howdy, you do not have to spend much to install a continuous ridge vent depending on the length of the roof 10 to 30' with a shingle appearance is not allot to have install . Consider getting a bid before you make up your mind. PS your welcome.

Re: Prep for finished attic

Attached is a photo of a cape several days after a snow storm.
You can see the garage is covered with snow. It is not heated. The snow on the roof of the house has melted from the heat escaping into the attic. There is an area mid roof where there is insulation that is marginally effective. The lower part has heat risng and being lost. Likewise the top.

Here is another cape where I spray foamed the roof.

The area where the snow is melted is over a stairway and the homeowner didn't want to open the ceiling to gain access. You can see how effective the foam is.

Yes, foam is expensive and you can't do it yourself. However doing it right will save you more in heating costs than it costs to do the foam. A lot of the work I do in these capes has even more to do with comfort issues. Once you finish off the attic your way, you will be stuck with an uncomfortable space. Many utilities have low or no interest loans to pay for this kind of work.

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