Flat Roof U Value 2016

Providing you with instant calculations all day everyday with step by step options and hints and tips along the way the no jargon u value calculator takes you through your construction build up until each element is included.

Flat roof u value 2016.

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. As with the chart the roof build up includes paving slabs a water controlling layer insulation 7 5mm holt melt waterproofing and a 200mm reinforced concrete deck. 0 25 column a is for extensions where the existing dwelling s walls and roof u values are worse than 0 70 w m k in the walls and worse than 0 25 w m k in the ceiling. U value has an inverse relationship to r value.

Column b is for other extensions upgraded existing thermal elements non exempt conservatories and conversion of unheated. If you have a target u value in mind then the calculator will give you the thickness of insulation needed. Flat epdm roof description. 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.

For the majority of flat roofs built up in a series of material layers each of a consistent thickness and performance the most appropriate calculation type is the combined method detailed in bs en iso 6946. Ecotherm s u value calculator is simple to use easy to tweak and provides an instant u value. R value state local al alabama 2015 alabama commercial energy code 2 r 25 3 r 25 state. U value of a flat roof.

The following table shows two different insulation options for an inverted roof in order to achieve a u value of 0 15w m 2 k. A lower u value indicates better insulation properties hence u value requirements usually specify a maximum value. State applicable energy ashrae zone minimum r value state local ms mississippi ashrae 90 1. Epdm rubber roof covering 19mm ply 50mm ventilated air layer protect vp400 plus lr membrane sip at specified thickness protect vc foil ultra insulating a vcl 25mm service void 50mm gyproc thermaline super.

State only ca california 2016 building energy efficiency standards 2 r 25 3 r 25 4 r 30 5 r 30 6 r 30 state local co colorado 2012 iecc. Check our library of roof u value calculations. Then simply adjust the thickness or the u value until you are happy and the calculator will do the rest. The thermal transmittance or u value of the complete roof system is calculated in accordance with established international standards.

Column b is for other extensions upgraded existing thermal elements non exempt conservatories and conversion of unheated.