You should of course see the manufacturer provided technical data sheet for the r value of specific products.
Roof insulation u values.
Recommended home insulation r values.
R value is essentially a product s resistance to heat flow which means that the higher the product s r value the better it is at insulating the home and improving energy efficiency.
R values represent resistance to the flow of heat.
We provide u value calculations to show compliance with current building regulations standards and best practice.
These r values are a sum meaning this should be the total r value once you add up the entire depth of insulation.
The higher the r value the better the thermal performance of the insulation.
The lower the u value the more insulation there is in a building element e g a floor ceiling or wall.
Therefore the less heatloss.
U values are the direct opposite representing the amount of heat that escapes through a material.
Knowing what r value and u values mean is key to following energy codes and to selecting products that best suit the climate zone you are building in.
For more information see our articles and how to videos below.
R value of various materials.
These can be supported with a detailed report.
A standardized insulation rating system ensures consistency with insulating materials rated in r and u values.
Insulation level are specified by r value.
The higher the r value the greater the resistance and the insulating value.
Reference table for u values u value is the coefficient of transmission i e the transmission of heat through the materials which compose the building s envelope or outer shell.
For a very good introductory overview article on r value see r values over at the website of.
Adversely u value measures the rate of heat transfer.
Consequently the higher the u value the more heatloss you have in the home.
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.
Column b is for other extensions upgraded existing thermal elements non exempt conservatories and conversion of unheated buildings.
The table below shows what levels of insulation are cost effective for different climates and.
Find your zone on the map and then use the above insulation r value chart to determine the level of insulation you need to properly insulate your attic walls floors and crawlspaces.
Here s a handy r value table that covers most types of roof coverings building insulation and a few other materials.
Notes to the table above.
U value has an inverse relationship to r value.
For example a building with material with an r value of r 11 converts to an u value of 0 09 1 r or 1 11 0 09.
U values are important because there are certain standards according to the building.
R value is a measure of insulation s ability to resist heat traveling through it.
The easiest way of getting a u value calculation is by using our free online u value calculator.