Refurbishing sash windows at home: how to repair a window sash

Today we are looking at sash window refurbishment at home. Some sash window repairs are quite simple to do at home and only require some basic tools and DIY knowledge. Of course, other sash window refurbishments are a lot more involved and may require the skills of an expert sash window restorer. Chameleon has years of sash window restorations under our belts, so we have some expert advice for you below if you’d like to tackle your sash window refurbishments yourself.

How to fix a sash window – identifying problems

A crucial part of refurbishing sash windows is identifying the problems and the issues. Here we have some common issues with sash windows that might need to be addressed. Depending on the condition of your sash windows, they may require all of these repairs or just one or two. Chameleon has covered how to insulate windows in a separate article, so the problems and repair methods for insulating sash windows won’t be mentioned below.

Sash cord issues

If your sash windows are not opening as they should, if they are binding on one side, or they are stuck open, this could be a sign of a broken sash cord. This isn’t the only issue that causes binding on sash windows, though. Sometimes paint within the frame can cause binding issues, which are much easier to repair. If the sash window is tilted to quite an extreme angle, though, this is likely an issue with the sash cord.

Wood rot

Rot can plague sash windows, particularly if the paint hasn’t been applied correctly or frequently enough. If you can see areas of flaking paint on the exterior of your window, there is a good chance that this area has some rot.

Broken glass

Broken glass in a window can be very easy to spot, but occasionally, the glass can break in the recess in the frame, making it a bit trickier to see. If you can feel a draught coming through near one of the panes of the glass, it could be caused by a broken pane, and the area should be examined closely.

How to repair a sash window

Once you have identified the issues that your sash windows have, you can begin repairing them. We are going to focus on repainting and fixing rot issues here but have other articles on the Chameleon blog about the common problems with sash windows we mentioned above.

First, you need to see how much rot your window has. If the paint is in good condition, you’ll likely only have a few areas of rot that can be easily treated. You must remove the paint first so that you can see all areas of rot.

Once this is done, the rot can be treated with a wood repair filler or wood hardener for rot treatment. These products penetrate the wood and make it hard again. Any areas of heavy rot should be removed and then filled. If the areas of decay are small, you can use a filler to replace the wood. If they are more extensive, you may need to replace the wood entirely. Again, we have double-hung window repair articles about replacing sections of wooden window frames on the Chameleon blog.

Once you have repaired any rot issues you can see, you can sand the windows, so all the repairs are flush. You can then prime and repaint the windows. Use good quality primers and paints for this job. Exterior paint is a must to ensure proper protection.

Using a sash window expert

If you feel any of the window restoration work is above your skill level, or you have a lot of sash windows to repair, it is worth seeking the help of a sash window restoration expert. Sash window refurbishment can be challenging, depending on the repairs needed. So, if you aren’t sure what repairs your sash windows require, don’t have time to carry out the repairs, or want to ensure the repairs last, seek a pro.