How to insulate my roof… no attic
I live in a house built in the 60s. It is a California Modern design (or so I’m told). It has very low roof pitch with 2 simple gable end roof sections. Inside it has exposed beam / vaulted ceilings. When you look up inside the house, you see 4 X 10 beams every 6 feet running as rafters would and then you see tongue and groove 2 X 6 roof decking running between the beams.
Bottom line is: there is no attic, there is no insulation whatsoever. There is only rolled roofing, felt, and one layer of 2 X 6 between the sun/rain etc… and the living room. It’s in Atlanta and when it’s over 85 degrees, the AC runs continuously.
The interior is beautiful… the beams and 2 X 6s are stained and polyeurethaned. I can’t insulate from the inside. It would ruin the look and the ceilings are already low.
I need to build up the roof from the outside. I’m very open to all suggestions…
Here’s one suggestion from a friend.
Remove existing rolled roofing. This will expose 2 X 6 tongue and groove. Glue and screw down 1/2 inch OSB. Lay 2 X 4 parallel to ridge sleepers every 2 feet with 1 1/2 inch foam board between them. Lay another layer of 1/2 inch OSB over the 2X4s and foam board and then either put roofing down… or add another set of 2 X 4 sleepers perpendicular to ridge on 16 inch centers with no foam board to create a ventilation space from soffit to ridge.
Comments / Suggestions are appreciated.
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