Thermal Performance – Part L
To comply with the 2010 edition of Part L of the Building Regulations, each floor’s thermal performance needs to be assessed individually in accordance with EN ISO 13370: 1998.
Determining the U-value of the Floor
1. Calculate the internal perimeter in metres of the external walls (P)
2. Calculate the internal area in metres of the floor (A)
3. Calculate the P/A ratio
4. Use the graphs to select the thickness and type of TETRiS required to achieve the desired U-value
Type and thickness of TETRiS required
Credits can be gained from four of the nine assessment categories detailed in The Code:
Category 1 – Energy [Ene 1]
15 Code credits are available for improving the DER over the TER. eg. ground floor U-values improved from 0.25W/m2 K to 0.16W/m2 K.
Category 3 – Materials [Mat 1]
Adopting a construction listed on the BRE website: www.thegreenguide.org.uk, which incorporates one of Cellecta’s insulation products can result in up to 15 Code credits being awarded.
Category 6 – Pollution [Pol 1]
1 Code credit is awarded when all the insulation materials in the elements listed below only use substances that have a global warming potential (GWP) of < 5, eg. TETRiS ecoblocks:
- Roofs: including loft hatch
- Walls: internal and external, including lintels and all insulation products
- Floors: including ground and upper floors
- Hot water cylinders, pipe insulation and other thermal stores
- Cold water storage tanks
Category 7 – Health and Well-being [Hea 2]
Incorporating one of Cellecta’s high performance acoustic treatments will also result in points being awarded. Contact our helpful technical team for further information.
The TETRiS system has been awarded a BRE Green Guide rating and gains 3 Code credits (element number 820140051).