Can electric cables be channelled into Recticel insulation boards?
No, as this would reduce the performance of the boards. Cables can penetrate the insulation with no detriment to the cable sheathing. Any cables penetrating or lying against insulation should be oversized to cater for increased operating temperature. If in doubt, consult a qualified electrician.
Can I use Recticel insulation products in a U-value calculation?
Yes. Recticel Insulation manufactures high-performance PIR insulation products for a range of wall, roof and floor applications.
The appropriate insulation product and thickness will depend on the construction build-up, required thermal performance and project requirements.
Use the U-value calculator to explore suitable construction and insulation specifications, or contact Recticel Insulation Technical Services for project-specific advice.
How do you calculate a U-value?
A U-value is calculated from the total thermal resistance of a building element, taking into account the different materials and layers within the construction build-up.
The basic principle is:
U-value = 1 ÷ total thermal resistance
Recticel Insulation's online U-value calculator can be used to assess the indicative thermal performance of different construction build-ups without having to calculate each layer manually.
How does insulation contribute to energy efficiency
Insulation reduces the transfer of heat through a building's walls, roofs and floors. This can help buildings retain heat during colder periods and limit heat gains during warmer periods.
High-performance insulation can therefore help reduce the energy required to maintain comfortable indoor temperatures over the lifetime of a building.
What does W/m²K mean?
W/m²K stands for watts per square metre Kelvin.
It is the unit used to express U-value and describes the rate of heat transfer through one square metre of a building element for a given temperature difference.
The lower the W/m²K value, the better the thermal performance.
What is a U-value?
A U-value measures how easily heat passes through a building element, such as a wall, roof or floor. It is expressed in watts per square metre Kelvin (W/m²K).
The lower the U-value, the better the thermal performance of the building element, as less heat is transferred through it.
What is the difference between a U-value and an R-value?
U-values take into account all elements of a construction, including thermal bridges. They can only be worked out by calculation. The R-value, or thermal resistance, is a measure of the insulation board on its own, dividing the thickness (in metres) by the thermal conductivity (lambda value, W/m.K). The R-value can be used to compare how different thicknesses of products with different lambda values perform comparatively.
What is the minimum clear cavity when using Recticel Insulation cavity wall products?
As per the documentation for Eurowall® +, the clear cavity can be reduced to 10mm due to the innovative tongue & groove interlocking joint.
Eurowall® Cavity is certified for use in conjunction with a 25mm cavity. However, some warranty providers will not accept this and require a 50mm cavity, as do Scottish Building Standards. A wider cavity should be used in exposed locations.
If in doubt, seek advice from your Building Control Officer.
Where can I buy Recticel Insulation products?
Recticel Insulation's products are available via number of stores across the country.
Why is U-value important?
U-values are important because they help assess the thermal performance of a building's fabric.
A lower U-value means less heat is transferred through the building element, which can contribute to improved energy efficiency and help projects meet their thermal performance requirements.