1 Sample Specification – Draughtproofing existing sash windows
When specifying draughtproofing for existing sash windows please consider the following wording to avoid the risk of a poor quality imitation system being used:
An approved draughtproofing system meeting the highest requirements (Class 3) of BS6375 Part 1, 2004 in relation to air leakage which tests to 600Pa – the equivalent of 71mph winds.
The system must incorporate a two piece parting bead to facilitate removal and re fitting during future painting.
The replacement parting bead section must be available in a variety of colours to suit the chosen paint colour for the windows.
The draughtproofing system shall incorporate a Sash Removal System including cord brake and housing, to allow sliding sashes to be removed internally for future painting and maintenance.
Energy performance of the windows to be no less than 80% of that achieved by a double glazed unit.
2 Sample Specification – New sash windows
When specifying new sash windows please consider some or all of the following:
- New sash windows by W. & J. Bolger Ltd.
- Frames & sashes to be manufactured in Accoya® wood
- Windows to be guaranteed for a minimum of 50 years against rot
Windows to be manufactured to traditional details including pulleys, cords and weights, fork jointed meeting rails, and having all dimensions and mouldings to exactly match the original windows / neighbouring properties / to exactly replicate all details found in typical properties from the same period / to exactly match architects details.
Spiral or spring balances will not be allowed.
Pinned on meeting rails will not be allowed.
New windows to incorporate Ventrolla or equal approved. (see above).