Underside Of Garage Roof Decking

The unfinished garage ceiling has 2x4 joists on 24 centers.

Underside of garage roof decking.

Essentially condensation occurs at night when the temperature inside a building is warmer than outside. Adding a sloped sheet metal roof under a deck to make a dry place to store outdoor stuff like the wheelbarrow or kids toys. The skeleton of a roof is formed with rafters or trusses generally spaced 16 inches or 24 inches apart from the center of one rafter to the center of the next. Plan to space the 2x4 purlins parallel to the house and 3 ft.

Special framing and moisture protection measures can provide mounting points for overhead light fixtures and ceiling fans. Most unvented attics incorporate spray polyurethane foam spf on the underside of the roof deck and attic walls. Under deck ceiling systems provide an all in one drainage and ceiling finish that is particularly suitable for areas beneath a deck that are high enough off the ground to provide a sheltered outdoor living space below. If the span under your deck is 12 ft for example the purlin at the outer end of the deck should be 3 in.

Warm wet air rises and meets the cold roof and cools. Position the foam board between the rafters and push it upward until it fits snugly against the underside of the roof deck. The portion of interior ceiling i am concerned with faces west so i thin it would make a difference to the garage temps if i. I am wondering if it is okay to hang insulation up against the inside of the roof in the garage.

Lower than the purlin along the house 12 x 1 4 3. That excess moisture ends up as drops of condensation on the roof. Picture a cloud of moisture floating overhead between the rafters. My question is about the unfinished interior of the garage.

To provide drainage the panels should slope toward the outside edge of the deck about 1 4 in. 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.