Underside Of Garage Roof Decking

Moving the air control layer and thermal control layer to the underside of the roof deck has significant advantages in cases where the hvac system is located in the attic.

Underside of garage roof decking. C 30 pieces of 2 4 lumber 97 1 4 14 pieces 6 1 2 rafters d 14 pieces of 3 4 tongue and groove plywood sheets 4 8 decking. B 2 pieces of 2 4 lumber 36 1 4 1 piece of 2 6 lumber 260 top ridge. Convert the space under a second story deck into a dry spacious patio by installing this simple under the deck roof and gutter system. The snugness of the foam itself should be sufficient to hold the strips.

Among the newest is the raintight system introduced at deck expo 2014. A 13 pieces of 2 4 lumber 144 long bottom rafters. My question is about the unfinished interior of the garage. That excess moisture ends up as drops of condensation on the roof.

This construction approach was first used in the 1970s and it has been implemented much more widely since it was first included in the international code council s icc model building code in 2007 irc section 806 4. I am wondering if it is okay to hang insulation up against the inside of the roof in the garage. A number of recently introduced under deck ceiling systems use corrugated aluminum or plastic panels designed to catch water that drains through decking and channel it away from the area below. Picture a cloud of moisture floating overhead between the rafters.

Position the foam board between the rafters and push it upward until it fits snugly against the underside of the roof deck. The unfinished garage ceiling has 2x4 joists on 24 centers. This illustration shows a sloped roof with cavity spray foam insulation sprayed on the underside of the roof deck and covered with sprayed on thermal or ignition barrier coating. Most unvented attics incorporate spray polyurethane foam spf on the underside of the roof deck and attic walls.

Adding a sloped sheet metal roof under a deck to make a dry place to store outdoor stuff like the wheelbarrow or kids toys. Warm wet air rises and meets the cold roof and cools. One of our readers rune eriksen sent us photos of his design for a home built deck drainage system and we were impressed enough to check it out. Essentially condensation occurs at night when the temperature inside a building is warmer than outside.