Hot Flat Roof Construction

The 3 most common materials used for flat roof construction.

Hot flat roof construction.

Flat roofs usually come with a 10 to 20 year warranty but can last 25 years if you build the roofs right and maintain them using commonsense rules. The term hot roof is something of a misnomer as the attic space will only be a few degrees warmer than in a. It must provide adequate protection against the elements keeping the buildings structure and interior dry. No ventilation is required for these types of roofs.

There are several methods and materials for the design of the exterior surface of a warm or cold flat roof. Attics typically have an insulated floor and have ventilation. Known technically as elastomeric or plastomeric roof membrane depending on the material single ply roofs come in a few different varieties including. Flat roof types.

A flat roof must be strong durable and stable throughout its lifetime. A warm deck roof is where the insulation is placed on top of the rafters joists and the roof covering is then placed over the insulation. Yet for historic modern style buildings like this old house s cambridge tv project flat roofs are at the core of the architecture meant to reflect the broad horizontal lines of the natural landscape. All three types of flat roofing cost 250 to 350 per square 100 square feet but prices vary according to region and size of the roof.

Hot tar and gravel. The roofs can fail if the roof assembly is not properly installed or insulated or if the outside air is unable to absorb moisture faster than it is accumulated. Flat roofs aren t architecturally logical as rain and snow will shed much more quickly off a sloped roof. A roof is defined in bs 6229 as a flat roof if it has a pitch of 10 degrees or less.

The membrane roof is the latest roofing technology and is also the roof of choice in commercial construction. Cold deck roof a cold deck roof is where the insulation is placed between the joists rafters or in between the ceiling joists in the case of a pitch roof. For that reason cold flat roof construction needs to keep in mind the need for unblocked airflow. Of course you don t need to live in a modern house to deal with a flat roof.

Unfortunately the term hot roof is a misnomer as the roof really is not that much hotter than a normal roof. Most studies show anywhere from 1 to 5 maximum increase in surface temperature during the sunniest part of the day while at night the surface temperature drops faster than a regularly vented roof. A hot roof is one where there is. The term hot roof comes in because the spray foam insulation is being affixed directly to the roof sheathing which removes the need for ventilation.