Attic space enclosed rafter or joist space above normally occupied and conditioned interior space assemblies as an economical arrangement of roofing and insulation materials.
Flat roof insulation requirements.
We recommend having at least 20 r value worth of material for optimal energy efficiency.
Any type of roof from tpo to epdm can be either hot or cold.
It depends on where the insulation is installed.
A note to consider before construction.
It is top quality and the most cost effective product for your flat roof.
The insulation may be fully or partially bonded to the vapour control layer or laid loose.
There must be a slope of 1 80 part h of the building regulations regarding drainage state that water should drain to one or two edges waterproofing should extend up the adjacent walls at least.
The international code council icc is a non profit organization dedicated to developing model codes and standards used in the design build and compliance process.
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.
The international codes i codes are the widely accepted comprehensive set of model codes used in the us and abroad to help ensure the engineering of safe sustainable affordable and resilient structures.
Hot roofs have the roof deck then insulation then the roofing material.
See the department of energy s doe ranges for recommended levels of insulation below.
A qualified roofing contractor will be able to advise on this but here are some of the main guidelines.
In most cases there will not be a loft in a building that features flat roofing.
Applicable roofing assemblies designers may view unvented attic i e.
Where insulation is mechanically fixed the fixings must be of sufficient length to.
How much ventilation does a flat roof need.
If insulation is installed below the flat roof deck this is called a cold roof.
Insulation requirements for roofs are therefore spread across ibc chapters 12 13 and 15.
Consider geography budget and use for the roof to determine the best option.
This means that your approach to insulation will differ from a standard pitched roof.
A cold roof or hot roof.
Laying flat roof insulation as a rule any roof with a pitch below 10 is classified as a flat roof.
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.
For a 1 inch board equivalent of 6 r value.
While expensive the best insulation is polyiso rigid foam.
From there the flat roof system you choose will determine the materials you apply.
Cold roofs have insulation beneath the roof deck which is beneath the roofing material.