Flat Roof Target U Value

The target u value for flat roofs on existing buildings other than dwellings are shown in table 4 below.

Flat roof target u value.

The u value calculator covers all the main ways of building walls flat roofs pitched roofs and floors using kingspan insulation products. If you have a target u value in mind then the calculator will give you the thickness of insulation needed. 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. 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.

When used in conjunction with spray applied foam any external weatherproofing must be of low vapour resistivity e g. Then simply adjust the thickness or the u value until you are happy and the calculator will do the rest. Walltite is applied directly to the underside of the plywood decking between the roof joists. 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.

Unsure what level of thermal performance you require. Get a u value calculation from our free online u value calculator or our technical department. The quick free and easy way to find out the insulation thickness and the u value you need for your building project. 0 18w m k 140mm of walltite.

Check out our guide on what performance is required for the uk insulation building regulations. Existing buildings do not require a target co2 emissions rate however they do require a target u value to meet for building elements walls floors and roofs. Using a target based methodology for new buildings in standard 6 1. Insulation for walls including cavity walls solid walls and timber or steel framed walls.

Flat roof or pitched roof insulation between rafters or roof with integral insulation. 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. Ecotherm s u value calculator is simple to use easy to tweak and provides an instant u value.