What are R Values
All insulation types are measured as an “R” value. The “R” stands for thermal “resistance”. Since warm air moves towards cold air (that’s wind!) it is a measure of how much a product resists heat moving through it. The higher the “R” value the better the insulating qualities. Therefore an R1.3 is lower in performance than an R1.6. The R1.6 has greater resistance to heat moving through it than the R1.3. Our recommendation is to go for as high an “R” value on your product of choice as you can, whilst taking a common sense approach towards “bang for buck”. We can offer you some practical advise on this.
Be aware that insulation R-Values can be measured in two ways. One as a measure of the product as a stand alone item and the other as a ‘system measurement’. The system measurement looks at how the product is installed and adds together components such as trapped air space, size of enclosed gap, house construction etc. Note that foils can only be measured this way as they work on reflection so the material itself offers very little thermal resistance. Looking at how a product will work in your home as a system is very important to getting the right result. A product may have a high R-Value but is this delivered in full to the your house once installed?