Roof Surface Temperature Calculation

7 5 cm of cellular concrete representing the top slab and the topping 2.

Roof surface temperature calculation.

The rooftop temperature results from two different properties. Ts to a id is hso a absorption coefficient of outside surface id direct solar radiation on surface. 1 roof square 100 square feet. Our roof calculator uses base length and base width to find the estimated area.

This calculator produced by lawrence berkeley national labs lbnl allows you to compute solar reflectance index sri and roof surface temperature based on solar reflectance and thermal emittance based on astm standard e 1980. To compute solar reflectance index sri and roof surface temperature based on solar reflectance r and thermal emittance e using astm standard e 1980. Calculating the surface area of a sloped roof can be time consuming without the right tools. 7 cm dead air space ventilation and spacer blocks ignored 3.

An approximate equation for the sol air temperature ts of the outside surface of a given wall or roof is. For the calculation of surface temperature and heat flux the roof figure 1 was approximated by three homogeneous layers figure 2. Area is defined as the expanse or measurement of a given surface and there are a few methods for measuring your roof s area. The base width is the distance from one corner of your roof to the other at its base on the short side of your house.

You want a roof area calculator that provides accurate estimates to help you order materials such as shingles membrane roofing or ceramic tile. 20 cm of cellular concrete. The house base area is the area of land that the house covers and for more complex shapes can be estimated using the area calculator. The following tools estimate the area of a roof as well as the amount of materials necessary to construct a roof of a given area.

The length l times the height h of a triangle is twice its area a2. The ability of the material to reflect the sun s energy back into the atmosphere called solar reflectance and the amount of heat the material rejects instead of absorbs called thermal emittance both are measured on a scale from 0 to 1 with higher scores translating into cooler roofs. Start the project with a roof area calculator. Input r and e in blue and green cells.

Your job is to calculate and illustrate the temperature gradient through a roof assembly composed of a gravel surfaced built up roof 3 4 inch thick perlite insulation 2 inch thick polyisocyanurate insulation two ply felt and asphalt membrane vapor retarder 1 2 inch thick gypsum board and metal deck.