Flat Roof Insulation Requirement

Insulation ratings are measured in r values per inch of thickness.

Flat roof insulation requirement.

Insulation is required to minimise heat losses in the winter and control excessive solar gains in the summer. Insulation for flat roofing is used to make a structure more energy efficient and minimise heat loss. There are two types of flat roof. Laying flat roof insulation.

Recommended home insulation r values. See the department of energy s doe ranges for recommended levels of insulation below. In this case ventilation is required and the roof can still become wet with condensation which may cause materials to decay. Another major performance issue with insulation and energy savings is its air sealing capability.

Achieving a u value of 0 20w m meaning your roof will be better insulated than your walls will need 120mm thickness of rigid foam or 200mm of mineral wool or natural insulation. The required u value will depend on the location of the project england scotland or wales type of building domestic or non domestic and the application floor wall or roof. With a flat roof this issue does not arise but the u value constraint and the amount of insulation needed is just the same. Insulation r values vary based on the type thickness and density of the insulation material.

There are many options available to fulfil this requirement as you will find out below. Cold roofs have the waterproof layer placed directly onto the roof deck and the insulation inside the roof just above the ceiling. R value is a measure of insulation s ability to resist heat traveling through it. A common differentiating criteria between different types of insulation is the amount of r value they provide when correctly installed.

Cold roofs and warm roofs. Insulation level are specified by r value. The tables below show the suggested u values in england wales and scotland. An r value tells you how well a type of insulation can keep heat from leaving or entering your home.

Flat roof insulation. What is flat roofing insulation. The higher the r value the better the thermal performance of the insulation. Typical recommendations for exterior walls are r 13 to r 23 while r 30 r 38 and r 49 are common for ceilings and attic spaces.

As a rule any roof with a pitch below 10 is classified as a flat roof.