If you have original sash windows, they’ve probably been in place around 100 years and in many cases, they’re still working just fine. They’ll continue to do so as long as you check them regularly and deal with any problems as soon as you spot them. You can download our quick and easy Annual sash window check to help you stay on top of any maintenance issues and save you money in the long run.
With replacement timber sash windows you can keep the beautiful look but also benefit from modern features such as acoustic glass, glazing and weather seals.
But if you’re happy with your windows, we won’t suggest you replace them if they can be fixed. We don’t repair sash windows but we’ve compiled a list of the most common problems and what you need to do. If you’re local to us and want a recommendation for someone to fix your windows, get in touch.
Problem |
Your options |
|
Rot |
|
| Rotting timber / Rotting staff bead / Rotten sill / Rotting bottom rail (bottom sash) / Rotting meeting rail (top sash) | Over time your timber might start to rot. Depending on the extent of the damage it should be filled and made good. If that won’t address the issue, splice in new timber to replace the rotten section. In some instances, you’ll need to replace the section of frame. |
| Rotting sill | We absolutely do not endorse the replacement of a sill. If the sill is replaced the but the window frame is rotten, you are storing up problems for the future. Depending on the extent of any rot we would advise replacement of the window in its entirety. We’d also suggest a trusted expert to carry out the work. |
|
Flaking |
|
| Flaking pointing | Hack out existing cement pointing bead and replace. |
| Flaking putty | Hack out putty and re-putty, then decorate |
| Flaking paint | A decorator will sand back or remove the oil based paint, fill any cracks, prepare the timber and redecorate |
|
Condensation and mould |
|
| Condensation on inside of glass (single glazed window) | Start by ventilating the room. If this doesn’t fix it, consider replacing the sashes or re-glazing existing sashes with double-glazing (if possible) |
| Black mould on inside of woodwork, especially around the glass | This is caused by condensation. Ensure the window is ventilated and don’t leave curtains /blinds closed in front of window during the day. Clean off with mould-remover. |
|
Sash issues |
|
| Broken sash cord | Re-cord the existing sashes |
| Rattling sash(es) | Adjust staff bead (bottom sash)
Fit weather seals (top or bottom sash) |
| Sash weights catching | Is something screwed into the box, such as plantation shutters? You need to remove any obstructions. You might need to remove the sash pocket to see better. |
| Sash weights knocking /rattling when window is opened or closed | The wag-tail may have moved (or wasn’t fitted) so the weights can knock. Or, as above, an obstruction in the box may be causing the weights to catch. |
| Sashes not lining up /closing easily | The solution depends on the cause. Start by removing any paint or dirt build-up on sill under bottom rail. Ensure sashes are square and plane them if necessary. If needed, replace hardware or pack out hardware if mid-rail is bowed or move the catches. |
| Damp patch under window | This is probably caused by water coming in through failed pointing, between a poorly sealed bottom sash and sill, or down the inside face of box lining. Get an expert to look at the damage to see if it can be repaired but you will probably need a replacement window. |
| Cracks in joints externally | This is usually caused by old oil-based paint that has hardened. A decorator will sand back, fill, prepare and redecorate the timber. |
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