Flat Roof Pitched Roof Detail

Figure 20 9 shows how a flat roof could be repre sented on the roof plan.

Flat roof pitched roof detail.

No upstand then you would have a ply layboard going up the pitch of the roof the equivalent of 150mm vertically. Often the flat roof has a slight pitch in the rafters. But now flat roofs often are constructed with fewer layers because of improved waterproofing technology. Roof deck providing the base for the waterproof membrane and in some cases the insulation.

The most important thing to know about a flat roof says tom is that it s not flat to prevent water from pooling and eventually invading the home flat roofs are always built on a slight incline at least 1 8 inch per foot. Some observers suggest it s harder to replace a flat roof than a traditional pitched shingle roof because of the labor required to remove its layers especially on older flat roofs. It has a slope of 2 3. The flat roof is economical to construct because ceiling joists are elimi nated and rafters are used to support both the roof and ceiling loads.

This could mean flat roofs may not raise the same red flags they used to. The high end of the ply layboard will have a cocking fillet fixed to it so that it provides a kick for the bottom course of roof tiles. Instead the roof must be done with a modified bituminous membrane e g. Flat roofs are hard to replace.

Can metal roofing be used on a low slope pitch roof. It appears to be flat but it needs a slope to allow the water to drain from the roof. When a flatty joins a pitched at eaves level i e. Many slope in several directions like squashed hip roofs toward scupper holes that connect to downspouts.

Armourvalley or other materials like epdm pvc or tpo covering. Figure 20 8 shows the materials commonly used to frame a flat roof. What pitch is a flat roof. Definition of roofs slopes flat roof a flat roof is defined by having a roof pitch below 15 degrees or a fall of 1 in 40 and can comprise of different products pitched roof a pitched roof is defined by having a roof pitch above 15 degrees or above fall of 1 in 40.

A flat roof isn t actually flat. The fall should never be less than 1 80 and preferably about 1 40. Flat roofs and pitched roofs exist side by side as equal partners. 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.

If flat roofs are to work well they have to have a slope known as a fall to shed rainwater. Waterproof membrane to prevent water penetrating the structure and interior of the building. A flat roof usually consists of the following.