Surface Temperature Of Roof

If the roof considered in figure 2 had a white instead of black surface i e.

Surface temperature of roof.

Y 2 qi to. The temperature of a vegetative roof at its surface is actually cool to the touch on most days it s in total shade with a conventional roof surface protected under a dense canopy of vegetation. Plot the calculated temperature gradient values for top surface of each material on the roof assembly drawing. On a hot sunny day the temperature on the surface of a traditional black roof can be more than 50 degrees fahrenheit 10 degrees celsius warmer than the surrounding air temperature source.

The difference between the maximum temperatures of black and white vertical surfaces is about 50 f degrees compared with 60 f degrees for horizontal surfaces. Ts to a id is hso a absorption coefficient of outside surface. Also primary importance of venting is to avoid ice damage by keeping roof surface sub freezing in high snowfall areas. An approximate equation for the sol air temperature ts of the outside surface of a given wall or roof is.

The results suggest that roof sheathing plywood and roof truss lumber temperatures which are the primary factors that influence thermal degrade of fr treated materials are primar. In hot weather for easiest handling temperatures should be below 90 f. A 0 4 instead of 0 9 the surface temperature would be 130 f instead of 190 f. You will be cover.

Z where 3 q heat flux heat flow towards inside is positive t temperature. Those are the recommended temperatures if you really need a need roof as long as you get 2 or more days above 30 f. Draw a line from the winter interior dry bulb design temperature to the next value and continue to connect the dots until you reach the winter exterior design dry bulb temperature. Sheathing temperatures recorded were 168 f 76 c for black shingled roofs and 147 f 64 c for white shingled roofs.

Department of energy. Inside air temperature was steady ranging between 23 and 24 c. The biggest temperature difference was about 9 degrees fahrenheit which occurred around noon.