Flat Roof Deck Slope

The slope of a roof or pitch is determined by how many inches the roof rises over 1 foot or 12 inches.

Flat roof deck slope.

The minimum pitch for a roof is 1 4 12 which translates to 1 4 inch rise to 12 inches of run. Roof coating and membranes serve a vital purpose for buildings and enclosures with flat roofs. Asphalt shingles require a minimum roof pitch of 2 12 or greater. To put it in perspective the angle of this slope would be around 30 degrees.

Metal roof shingles require a minimum roof pitch of 3 12 or greater. Flat roofs which aren t perfectly flat require a small slope to allow for water runoff. There are roof coating. Low pitched roofs are generally difficult to maintain and you need special materials to prevent leaks.

Roof deck framing unlike for decks at ground level doesn t entail a ledger attached to the rim joist of a house. Along with the benefits of a flat roof come unique challenges. However you can only use this pitch with built up roofing or specialized synthetic roofing. Clay and concrete tile requires a minimum roof pitch of 2 1 2 12 or greater.

Of course the best designed flat roof has the correct amount of pitch to drain the water off naturally. Let us recap on the minimum roof pitch required for each type of roofing material. The deckseal self adhered roofing system is an excellent solution for low slope applications 1 4 12 to 2 12 on residential re roofing jobs. They just require more thoughtful construction and maintenance.

Membranes and coatings are designed to create a strong seal to prevent leak when water begins to build. Your building and location can help determine which drain will fit your roof needs. Instead a pair of beams rest on supports called sill plates to create a frame for the deck. Generally such roofs have a pitch ranging from 1 2 12 to 2 12.

An example for a steep sloped roof is 8 12. The owens corning deckseal roofing system offers numerous advantages over competitive low slope products. Flat roofs are incredibly versatile and many homeowners choose to transform their flat roof sections into roof decks. Although sloped roofs are generally easier to maintain and provide more reliable insulation flat roofs are advantageous in their own ways.

A deck on a sloped roof requires a different approach to the framing underneath the joists. The different types of coverings can be overwhelming and confusing so here is a breakdown of the basics for each one.