Concrete Floor U Values

Uninsulated u value u 0 21 0 25 0 36 0 50 0 62 0 73 0 83 0 92.

Concrete floor u values. The jablite u value calcutator gives instant access to multiple u value calculations for jablite insulation products in wide range of applications. Welcome to the jablite u value calculator for floors walls and inverted roofs. Reference table for u values u value is the coefficient of transmission i e the transmission of heat through the materials which compose the building s envelope or outer shell. Air gaps in insulation mechanical fasteners penetrating the insulation layer precipitation on inverted roofs.

U value has an inverse relationship to r value. Dt temperature difference o f k. A reasonable r value for a normal concrete slab can be estimated using an r value the thermal resistance per inch of thickness between 0 1 and 0 2 and multiplying it times the slab thickness. 8 2 equivalent r values for concrete walls and rofs.

There are a few good u value calculators online that if you are short on time are worth. For example a building with material with an r value of r 11 converts to an u value of 0 09 1 r or 1 11 0 09. Average heat transmittance mum relative humidity value of roof. While the values do vary for each particular material and method of construction the following table gives general figures for some common modes of construction.

The corrected u value u c is obtained by adding a correction term u. A wall area ft 2 m 2. Corrections to u values of roofs walls and floors annex d of bs en iso 6946 provides corrections to u values to allow for the effects of. U value requirement windows whole window u value 1 4 w m k.

The above formula shows that only floor plans with p a ratios less than 0 1253 will meet the new building regulations without additional insulation. U values of typical building methods u values overall coefficient of heat transmission indicate the heat flow through materials the higher the figure the higher the heat loss. Dew point temperature of value of floor room air at design maxi uo. Using the figures above we can calculate the effective thermal resistance of the uninsulated floor m k w this is the reciprocal.

U value requirement floor 0 13 w m k. The overall heat transfer coefficient the u value describes how well a building element conducts. U overall heat transfer coefficient u value btu hr ft 2 o f w m 2 k. For a 6 inch slab r value would be between 0 6 and 1 2.

For example a wall with a u value of 0 25 would have a resistance value ofr 1 u 1 4 25 4 0. U value requirement semi glazed doors 1 2 w m k. U c u u. This easy to use interactive tool is designed to help calculate the thermal performance of varying combinations of insulation and blocks including aircrete and aggregate blocks.

Calculating the inverse of that 1 r would give you a u factor in the range of 1 67 to 0 83. U value requirement roof 0 13 w m k. The heat transmission through a building wall or similar construction can be expressed as.