CONSERVATION OF TIMBER SASHAND CASEWINDOWS
Replacement of bottom rail at base of sash stile of lower sash
Replacement of base of o face of sash stile
joints at base of lower sash
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Strengthening joints
Rail and stile repairs
they may be replaced by a piece of matching crosssection. This is best done in complete lengths to ensure they are securely fixed.
profiles that exactly match the existing. Samples may have to be run using the proposed metal profile cutters before approval for use (illus 71).
Where weight boxes are provided with removable covers these may be defective or missing, and replacement should be camed out to the original profile (illus 72 and 73). This work is often done while accumulations of debris are being cleared from the base of weight boxes (see 7.3).
6.1.4 Frame repair Repairs may be made to frame members using the same techniques as used for sash repairs. It is usually possible to repair frames in-situ and this is preferable as, where timber decay is present, frames can become distorted during their removal and may become unsuitable for re-use. Special tools are required to rout out decayed or defective timber to allow new wood to be spliced into place, replicating the necessary jointing. Always ensure that decayed timber is completely removed, as any remaining rot will continue to decay behind the newly indented timber.
The decay of cills is one of the most commonly occurring defects in sash windows, as they are subject to constant wetting. The complete cill can be replaced in-situ,together with the lower parts of the outer lining and pulley stile (illus 74 and 75). Where decay is more limited, and to avoid unnecessary disruption of an otherwise sound frame, the outer half of the cill only can be replaced (illus 76). Full cill repair is complex but if correctly camed out will ensure adequate protection of the sash window. Half-cill repairs tend to
Sections of parting beads or baton rods that are damaged or decayed can be pieced-in, or commonly
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