windows and doors
Where external wall insulation is installed but windows are kept, a reveal board and extended sill is required. This can be a proprietary woodfibre reveal board, a foam insulant reveal board for smaller depths or an insulated stainless steel window surround.
Where internal wall insulation is installed with existing windows, either a timber reveal or a plastered woodfibre board can be used.
Where new windows are installed, this is doing using a timber window box that allows the window to sit at the outside of the external wall insulation to maximise light and minimise cold bridges, forming a timber reveal inside the building.
We work with Green Building Store to install high performance new triple-glazed low-e argon filled timber windows with warm edge spacers. These are fitted in order to be air-tight and with minimal thermal bridging. Performance target : 0.8 W/m2.K.
Green Building Store also manufacture and install replacement triple glazed patio doorsets Performance target : 1.0 W/m2.K.
If new windows are too expensive, it is possible to replace the opening casements within the existing frames with triple-glazed low-e argon filled timber windows with warm edge spacers. Performance target : 1.0 W/m2.K.
Alternatively fixed glazing units can be replaced within existing frames with triple-glazed high performing glazing units. Performance target : 1.2 W/m2.K.
Red can arrange unusually shaped windows, including Oriel windows and "Manchester" windows, in triple glazing.
Where it is desirable to retain old sash windows these can also be refurbished : existing staff beads and parting beads are replaced including brush seals, with additional brush seal routed into the back of the lower casement at the central join, existing glazing replaced with double-glazed low-e argon filled timber windows with warm edge spacers. Sash cords are replaced, additional lead weights as required by the additional weight of the improved glazing.
For non-opening windows including stained glass panels or glass blocks, high performance double glazed secondary glazing units can be fitted inside as a second layer. Existing window frames are fully draft stripped and re-sealed to improve air-tightness. Performance target : 1.4 W/m2.K.
If doors are to be replaced, insulated timber external wood flush doorset Performance target : 1.1 W/m2.K.
Further information is available in the Retrofit Pattern Book