I’m helping with a project here at Lake Wildwood. We have a laminated timber frame constructed Lodge building that is around 40 years old. It was built with curved/arched Glue Lam. Beams, and T&G wood roof decking, with 30 yr. Dim. asphalt shingles over 3/4″ rigid foam insulation, and plywood. No air space was allowed between the roof deck and the shingles, and no ventilation of any kind, I’m not sure if, or how felt paper may have been used? It needs a new roof, the shingles are around 15+ years old and show much wear and deterioration in some areas.
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Hi,
I’m not sure if I’m in the right place, but I was looking for any information you
may have on insulating and roof venting.
I guess you could say we’re trying to get the “most bang for our buck”. We want to have the job done right to get the best performance by the most cost effective means. I was just wondering if you have any information and/or recommendations for the proper way to insulate, ventilate, and re-roof a building with this type of construction? Any help, and/or guidance would be appreciated.
Thank You,
Mark
p.s.
F.Y.I., The building is not currently air conditioned,
but may well be in the future. It has forced
air heat which is used sparingly, and a gas
fireplace. Lots of large insulated windows
and doors.
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Replies
I saw an article in the magazine a few months back ware someone built another roof frame over the existing roof sheathing and then foamed the space to get the r value they were looking for. I would search the archives for that article because it might be exactly what you want to do. Thanks Jay
You're in the right place. I'm surprised you haven't gotten more responses. This will bump you up to the top for another run.
FKA Blue (eyeddevil)
Sounds like a reasonable way to build under the conditions. I'd increase the rigid foam to one and a half use a foil faced product on the bottom on strapping to hold it foil side down off the T&G. Stacked up like this T&G, 3/4" strapping, foil-faced isocyanaurate foam foil side down, 3/4" EPS (blue styrofoam), 1/2" OSB, tar paper, 30 year shingles.
Occasional heat, occasional AC, probably not much concern about condensation on the bottom of the foam. The air gap makes the most of the foil and lets the T&G breath. For walls you would put the air space behind the siding as a rain screen and face the foil out towards the airspace. This is just for occasional use buildings that need to warm up fast. (ie pole barns and such)
Hope this is what you were looking for.
M
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"You cannot work hard enough to make up for a sloppy estimate."