Timber window sills and sashes usually become rotten due to -
Insufficient paint cover .
Adjacent pointing missing or damaged allowing water to get between the wooden sill and the buildings sandstone or concrete sill.
Where the sill meets the pulley style, water attacks the end grain joints, as demonstrated in the video clip above.
Glazing putty missing or damaged allowing water to attack the glazing rebate, spreading through the entire rail.
Excessive condensation build up internally, attacking the sash rails from within and effecting their tennon joints integrity.
Replacement sills
If your sill or sash is beyond repair with resin then it is time to fit a new one. We can supply and fit new sills to match the exact size and profile of your existing window.
Sills are available in softwood or hardwood, hardwood giving a longer life span. However most people opt for softwood. This is mainly due to cost and also because hardwood comes from a rain forest somewhere in the world which is not really sustainable, compared with managed pine forests.
Replacement top or bottom sashes
Single glazed sashes come in all shapes and sizes. We can remake anything that is required, even curved - bowed on plan sashes. If your sash requires astragals (glazing bars, separating panes of glass) we can replicate the pattern required. We will glaze and putty the sash, usually with toughened glass, and fit this back into your sash box so that the profiles and mouldings match the rest of the window, blending new with old.
We prefer not to try and fit double glazing into the new or old sashes due to the following reasons,
Slim line double glazing is still not an exact science. The cavity remains very small not offering much thermal advantage.
Double glazing makes the original sash heavier, requiring the weights to be changed, increasing expense.
The heavier glass puts more strain on the windows tennon joints.
The putty bead holding the glass in place is reduced, due to the glass being thicker, making glass less secure.
Some listed building areas do not permit the fitting of double glazing.
