Typical Residential Flat Roof Detail

The parapet roof by far the most common type of flat roof isn t actually flat at all.

Typical residential flat roof detail.

Cold roof insulation between rafters wnapor barrier on warm side below orw sheatiiing roofing roofing 2 x 8 sleepers notched for vent aligned wi rafters flashing over rooang fascia sheatiiing 2 x 4 sleepers aligned w rafters provide. This will help you create a flat roof framing plan. Some roofs actually slope in several directions ensuring optimal water runoff. Traditional homes often have sections of flat roof over shed dormers above porches and garages and on balconies.

Andrew t boyne architect. Other roof protrustions sothat notiiing obstructs tiieflow ofair from eave to ridge. The sandwich warm deck roof is the most common type of flat roof. Cad details document name pdf dwg download all cad construction details 37 1 mb 3 4 mb mc01 identification of roof areas 694 kb 167 kb mc01a single layer underlayment 678 kb 302 kb mc01b double layer underlayment 711 kb 322 kb mc02 vent pipe flashing 626 kb 349 kb mc03 valley.

From there the flat roof system you choose will determine the materials you apply. Most often used in commercial and industrial applications this flat roof system contains layers of waterproof membrane such as a treated fiberglass basemat tar and gravel to seal the flat roof surface. A classic flat roof is either almost completely level or has a very slight pitch of 3 in 12 inches or less. Of course flat roofs are not flat but have a very slight roof pitch of between 1 4 to 1 2 per foot.

Underneath the basics flat roofs are usually constructed with a ceiling nailed to joists which support a deck usually wood in residential construction a vapor barrier insulation and a roof board. A parapet roof involves a typical sloped roof that is concealed behind a parapet wall so that it gives the impression of being flat. But flat roofs take a pounding from harsh weather which is why they rarely last as long as a good sloped roof. The insulation is placed below the waterproof covering and is either mechanically fixed or bitumen bonded on to the top of the deck.

Inverted warm deck roof the insulation boards in an inverted warm deck are laid over the structural deck and the waterproof covering. This flat roof system is still used in some residential applications because of its affordability and fire resistance. Most flat roofs are typically not as long lasting or durable as sloped ones because the latter shed snow and rain a lot quicker. Of all these membrane types epdm synthetic rubber is the most common single ply membrane roof material in both residential and commercial use.

However over the last few decades new and advanced materials have been developed. Just enough slope to drain water but also flat enough to be a problem if not constructed properly. You can do this with a foam layer that exactly fits your roof.