Minimum Roof R Value For Tapered Insulation

This bulletin presents the theory and calculation methods used to develop tables of effective r values for tapered insulation.

Minimum roof r value for tapered insulation. For a very good introductory overview article on r value see r values over at the website of. Find out why in the seller s fact sheet on r values. Tapered roof insulation systems are designed to provide a 1 savings vary. A properly designed tapered roof insulation system not only provides the necessary r value and the support for the roof system but it helps extend the.

State applicable energy ashrae zone minimum r value state local ms mississippi ashrae 90 1 2010 2 r 20 3 r 20 state local mo missouri 2012 iecc 4 r 25 5 r 25 state only mt montana 2012 iecc 6 r 30. Slope cross sections published feb. The goal of tapered roof insulation systems is to eliminate ponding standing water on a membrane when the roof deck does not provide adequate slope. The r values shown above are the minimum r values required to meet code requirements.

Minimum insulation r value requirements non residential above roof deck. One area where effective u values are commonly misunderstood is tapered insulation for low slope roofs or at the eaves of sloped roofs. When correctly installed tapered insulation helps eliminate problems due to ponding water and can extend the longevity of your low slope roofing system. Since a tapered insulation system will increase thickness away from the low points the overall system r value will.

How does this affect r values on a tapered insulation system. It is readily available in the two most popular and efficient tapers 1 8 3 18 mm per foot 305 mm 1 and 1 4 6 35 mm per foot 3 18 mm 2. View document share this post. R 20ci r 25ci r 25ci r 30ci r 30ci r 30ci r 35ci r 35ci question.

You should of course see the manufacturer provided technical data sheet for the r value of specific products. Higher r values mean greater insulating power. R value of various materials. Standard material is johns manville enrgy 3 tapered and flat polyisocyanurate roof insulation.