Optimum Roof Overhang

With composite siding such as boral s truexterior siding over a ventilated rain screen and with properly executed flashing at the windows and doors the walls on the fhb house will be able to handle rain just fine.

Optimum roof overhang.

Those larger than 2 feet wide have to withstand very high uplift so they should be engineered. Oversized overhangs can increase the risk of roof or truss uplift. They are essential for framing and shading windows reducing splashback and getting rain to fall far enough away from the foundation. An important component of passive solar design is calculating building openings doors and windows and roof overhangs.

24 dec 2012 02 45 pm. Optimum overhang dimensions for energy saving 295 sun fig. But are they really necessary. Jonr senior member posts 5341.

Because the sun travels a higher path in the sky in the summer than in winter the overhang blocks. If the building element bears more than about 30 off true south the effectiveness of an overhang as with any solar feature begins to decrease significantly. Borst engineering construction llc competence integrity and professionalism are integral to all that we do. Roof and overhang systems should be designed to resist wind uplift especially in hurricane prone regions.

The size of the window width and height and the window s relationship to the roof the space above the window influences the direct. There isn t general rules to size an overhang. Doing so keeps basements and crawlspaces dry and it also helps to. Figure 2 illustrates how this is possible.

Roof overhangs should be no more than 2 feet wide. Roof construction and materials considerations roof decking. How roof overhangs work. Roof overhangs might look relatively routine but there is a lot of design thinking that goes into creating the optimal dimensions for each one.

The optimum depth varies with the latitude and the type of climate. Geometry of overhang separated from top of window. You can use the free software sketchup to draw the house and it will draw sun shadows for any date time at your location. For high wind resistance use 7 16 inch or 19 32 inch plywood or osb roof decking attached with nails not staples.

Roof overhangs at the eaves and rakes protect the walls below from rain and sun. Overhangs are most effective for south facing elements in the northern hemisphere and at midday. Borst passive solar roof overhang design calculator.