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U Value Insulation information

1st October 2010: There are now different requirements for Replacement, Extension and New Build frames and doorsets.
Understanding that there IS a difference we have to know the project type to give the best quotation & price compliant product.

U-VALUE AND WHAT IT MEANS TO YOUR PROJECT

The following information summarised from Building Regulations Documents L2A (New Dwellings) 2010 & L2B (Existing Dwellings) 2010.

Fitting (a) Limit for new fittings in new dwellings (b) Limit for replacement fittings in an existing dwelling
Pedestrian doors with more than 60% of their external face area glazed 2.2W/m2K 1.8W/m2K (or exempt if fitted into existing door frame)
Other pedestrian doors 2.2W/m2K 1.8W/m2K (or exempt if fitted into existing door frame)

The following is general advice given by Jeld Wen:

What does it mean to our customers?

Part L 2010 Doors

Replacements & Doors in extensions (to existing dwellings)

  • Maximum U-Value = 1.8 W/m2K where glazed area of door is less than 60% and fitted into a new frame. Exempt if fitted into existing frame.
  • Maximum U-Value = 1.8 W/m2K where glazed area of door is greater than 60% and fitted into a new frame. Exempt if fitted into existing frame.

New build: Determined by Building Design

  • U-Value (range) = from 1.1 up to 2.2 W/m2K (weighted average). We recommend that you consult with your architect for clarification.

Non Thermal Break (between a house and a heated porch)

  • Exempt as insulation in this situation is not a requirement. The insulation comes from the porch door/windows.

New build: Determined by Building Design

U-Value (range) = from 1.1 up to 2.2 W/m2K (weighted average).

Summary (for doors)

Is it a replacement? – Maximum U-Value of 1.8 W/m2K

Is it an extension to an existing building? – Maximum U-Value of 1.8 W/m2K

Is it a new build? – The customer must provide the U-Value but maximum allowable 2.2 W/m2K as set out in Table 3 of Approved Document L2A

N.B. Please note that while every care has been taken to ensure this information is correct, changes to requirements do change. We recommend that you confirm with your local building control officer before sourcing a door to ensure that it complies with your requirements.