Flat Roof Pitch Design

The pitch of a roof is arrived at by dividing the vertical rise and its horizontal span or what people in the roofing industry would refer to as the slope.

Flat roof pitch design.

Flat roof design guide. Flat roof slope the slope of a roof or pitch is determined by how many inches the roof rises over 1 foot or 12 inches. Flat and low sloped roofs look striking on a wide variety of architectural models especially on contemporary house designs. Flat roofs are built with a slight pitch of at least 1 8 per foot so water can drain either to centralized drains scuppers or a gutter system.

Some local codes take it a step further allowing a slope of only of an inch per foot. The smallest pitch of a roof is 0 5 12. Regardless of how new or modern a house is there is a good chance that it will be topped off with a flat roof now but if you can t picture how great they look we. From there the flat roof system you choose will determine the materials you apply.

A common choice for flat roofing material is epdm rubber as it is highly durable waterproof and can be made from recycled materials. There are different kinds of roofs and all these have particular specifications for their installation. Normally 1 80 0 72 is the recommended minimum angle for a slope and this is universal across the vast majority of flat roofing systems regardless of the materials that they incorporate. Flat roofs are typically designed with a pitch of 10 degrees or less.

In order to ensure a finished surface with zero fall a design fall of 1 80 should be used and a detailed structural analysis should account for construction tolerances settlement and for. Roof pitch in layman s language simply refers to the steepness of the roof. In fact many residences have sections of flat roof on porches balconies garages and room extensions which appear so attractive. It should come as no wonder then that these are experiencing a serious comeback right now.

This means that the rise of the slope goes up or down 8 inches for every 12 inches. On larger roofs it s probably cheaper to use tapered foam insulation on top of the roof sheathing. An example for a steep sloped roof is 8 12. A completely flat roof is a poor design as water and snow will collect on it eventually leading to your roof collapsing in from the weight of it all.

According to the international code council the minimum slope for water runoff is inch per 12 inches. This modest slope can be achieved in a number of ways.