Flat Roof Insulation Requirements

There are two types of flat roof.

Flat roof insulation requirements.

From there the flat roof system you choose will determine the materials you apply. There are many different types and installation methods out there along with a lot misinformation about which products offer the greatest energy savings. Here we share the most common mistakes people make when installing flat roofing insulation. Continuous insulation zones ashrae 90 1 ashrae 189 1 igcc ibc iecc 2004 2007 2010 2013 2016 2009 2011 2014 2012 2015 2009 2012 2015 0 25 1 15 20 2 15 20 25 3 15 20 25 4 15 20 302535 5 15 20 302535 6 15 20 3035 7 15 20 3540 25 8 20 3540 25 minimum r value non residential above roof deck.

Different types of roofing insulation exist including blanket insulation blown insulation and rigid insulation. 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 material is placed on top of the roof rather than in between the ceiling and the decking. A cold roof or hot roof.

U value of a flat roof to comply with part l of the building regulations 2010 all roofs to rooms except those in unheated buildings should be thermally insulated to a maximum u value of of 0 18 w m k. If insulation is installed below the flat roof deck this is called a cold roof. Insulation can also help to limit condensation and contribute to acoustic insulation depending on the type of insulation used. In this case ventilation is required and the roof can still become wet with condensation which may cause materials to decay.

Hot roofs have the roof deck then insulation then the roofing material. Cold roofs and warm roofs. 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. With a flat roof however this becomes a major concern.

Any type of roof from tpo to epdm can be either hot or cold. Cold roofs have the waterproof layer placed directly onto the roof deck and the insulation inside the roof just above the ceiling. Consider geography budget and use for the roof to determine the best option. The type that is right for your flat roof insulation job depends upon the state of the roof expert opinion on the best type and your budget.

Cold roofs have insulation beneath the. It depends on where the insulation is installed. Insulation is placed in between the joists underneath the roof surface above. Both these variants require different approaches to insulation which will be covered in this guide.

A note to consider before construction.