The popular perception about the good old-time sash windows is that they are rattling, letting draft in, loose and sometimes even impossible to close fully. While this might be true in some cases, those are usually related to the poor maintenance of the sash windows in question. If kept properly, even an original 19th-century sash window can provide the same quality and security as modern double-pane units that cost significantly more to purchase, install and maintain. It is not necessary to be a professional handyman to do the repairs which we are about to discuss – with the right tools, attitude and enough dedication you will be able to get the most out of your sash windows.
One thing you should keep in mind is that you can always purchase a set of brand new aluminium sash windows from a trusted local company, like Colin’s Sash Windows. If, however, you are into DIY home projects and you would like to preserve the spirit and character of your house while keeping it comfortable and adequately insulated, keep reading.
Fixing old sash windows is not that hard
Fixing sash windows involves a few basic steps that you will need to follow:
- Removing the sash
- Freeing the glass
- Cleaning the joints
- Applying epoxy
- Priming the sash
- Bedding the glass
- Inserting points
- Tooling the putty
- Re-hanging the sash
Be advised that the whole process may take several days to complete, so set aside enough time on your schedule before you commence with the repair of your sash windows. It might be a good idea to look at the weather forecast too and take it upon yourself to do all those things only if there is a low chance for heavy rain or wind in the week to come.
|Why is it necessary?
|Work wet – mist all surfaces and wipe them down with paper towels while working.
|You will remove any lead-residue without risking inhaling it.
|Isolate a work area at least two and a half metres from any other surface.
|Avoid the risk of contaminating items and surfaces in your home with lead.
|Designate work clothes you wear only in the containment area.
|Hinder spreading of unwanted particles in your property.
|Purchase proper gear – hat, goggles, and a respirator.
|Protect yourself from any lead residue on your sash windows.
|Main a good workplace hygiene
|Avoiding eating, drinking, smoking in the containment area, as well as washing yourself thoroughly every time you leave it will eliminate health hazards.
*If your property was built prior to the 1980s, chances are that there are traces of lead-based paint on the windows
Hanging the windows down and removing the glass
Start by removing the stops on the lower sash – you will have to either unscrew them or pry them off. Proceed by pulling off the lower sash and taking off the cords and chains on both sides. Go on by doing the same with the ones on the upper sash. Do not forget to put every item you take apart in a bag and label them to avoid confusion when putting everything back together.
You might need a heat gun (set on medium) to deal with old, hard putty. Once it softens, you can use a specialised knife to remove it and pry the glass off the frame. Take a look at the joints. If your sash window is old, chances are that there are pieces of soft or rotten wood inside that you will need to remove using a rotary tool.
Fixing the problems
The next step is to restore the joints you have just cleaned. To do that you will need an epoxy primer that you will need to apply on a brush and let it stay for some half an hour (read the label for more precise timing). Mix the primer with the second part of the filler and restore the original shape of the joint by carefully and evenly spreading the epoxy on the inside. Set aside the sash and leave the epoxy to fully dry for at least 24 hours.
Use grit-paper to hand-sand the sash. Of course, do not forget to carefully wipe any residual dust. Once you are done, it is very important not to forget to apply a coat of oil-based primer on the wood to seal it. Otherwise, you risk turning the sash permanently brittle – a very real risk in the damp British weather.
I'm the founder of Colin's Sash Windows. I disrupted the sash windows market in the UK in 2014 by introducing fixed prices for uPVC sash windows in the UK. Before this they were generally only available at very high prices through window installers. Today our business is one of the market leaders in supply only windows, doors and roofs in the UK.