Repairing old wooden windows as a DIY job

[montyjohn]

Hello,
I'm close to buying a G2 listed house with mostly wooden single glazed windows and a few cheap nasty PVC windows at the rear. It's a very handsome Georgian property.

Most of the windows appear to be circa 1990's (from talking to neighbours) single glazed wooden casement windows (non sash). Unfortunately there is only one window that is what might be a historic sash with it's iconic six glass panes per casement, with old looking wobbly glass (annoyingly one pane is cracked, assume these can be sourced somewhere to look like original).

When walking around with the surveyor he was suggesting repair costs of around £1500 per window to replace rotten sections of frame (bottom of window). There are probably about 5 windows to do, with the rest just needing minor maintenance.

I'm fairly handy. I fitted my last kitchen for example, using a jig and router to create a seamless joint on the laminate worktop. You take your time and with the right tools it came out fine. Built the odd cabinet, shelves etc. I'm more mechanically minded to work on cars, welding etc, but comfortable trying anything, apart from plastering (bad memories, although I will be trying this again soon with more realistic expectations).

So I have this possibly arrogant, maybe naïve idea that with a router table (this has nothing to do with the fact I want an excuse to buy one) and a planing table (again, always wanted one) I could make replicas of the rotten parts and reassemble. I don't know how they are held together, but would probably just use a simple biscuit joint. I'd start with the 1990's windows as there is no historic value here anyway so I wouldn't feel the need to consult the CO and would do a like for like repair. When experienced and confident I would work on the historic window.

By which point, would it be that naïve to assume I could build my own windows to replace the PVC (with CO/LBC) I was thinking I would build one as an experiment, and use it as a sample of what I want to use for discussions with the CO. Built to match the only historic window. Not needing FENSA on listed building makes this all possible in theory.

I'm probably going to try some of this regardless of the responses and sound advice I get as I like learning things the hard way. You learn a lot by failing.

I was just wondering how many out there do this type of repairs themselves to get a sense of how realistic my plans are?

 

[stuart45]

I've been repairing my timber single glazed casement windows over the years when needed. I've used a combination of timber replacement and filler. If I'd had to pay someone to do the job it would be cheaper to stick new windows in. I'm a bricklayer, not a carpenter, so I'm not an expert with timber repairs. You sound a lot more knowledgeable than me, so I'm sure you'd be capable of doing the work.

 

[fernicarry]

All very feasible if you have the time and inclination and the right toys. This is pretty much the path I went down partly inspired by posts on here. If you search the forum you'll find plenty of information.

I had a small local outfit repair the cills and cases on some of my windows and tbh the quality of the workmanship was a bit meh, so the next ones that were due I decided to have a go myself. In this part of the world I can get cill sections off the shelf made to the correct profile. They would be quite involved to make otherwise. I've since graduated to making small sashes myself. Similarly to your plan I made up the stiles and rails on the router table with a profile that closely matches the other windows and then assembled them with simple butt joints relying mainly on glue and the odd pocket screw. Add plenty of sash clamps to your shopping list. I've now obtained a morticer so next time I'll do "proper" joints.

The limitation with a router table is the size of the cut you can make. I ran into this with my little fake-sliding sash when I had to put an angled rebate along the bottom edge to match the profile of the cill. I found a large panel raising cutter that was close enough to the profile but its a very big and heavy beast and is quite terrifying in operation. About on the limit of what is possible and/or advisable. Manhandling the completed sash across the table wasn't the easiest (because the cut needed to go across the bottom of the stiles) so the profile is a bit wobbly but its serviceable. A related point is that you need enough space to work comfortably around your machinery otherwise you are constatly rearranging things to do part of the job, then again for the next part etc.

Similarly with planer/thicknessers. I have the Makita one which is absolutely excellent but its bed width is only 300mm so that can rule it out for some jobs. Its still extemely useful and gets used a lot. Once you are no longer beholden to off the shelf timber sizes that opens up a world of possibiltiies. For larger jobs you can start with rough sawn timber thats an awful lot cheaper than dressed from a timber merchant so the tools may even pay for themselves!

 

[Flyfisher]

Ditto. I've always been 'fairly handy' and enjoy the challenge of such things. I consider myself reasonably competent and able to achieve a decent finish but I am painfully slow and could never make a living from such things, so it's a good job I was retired before taking on our house! One thing I have learned is to not skimp on tools. Yes, a decent router or planer/thicknesser can be expensive but the beauty of DIY is that it can save more than enough to pay for good tools and machinery, even if it's just for one job. The trade-off is your time of course, which can only be a personal decision but it certainly works for me. So if you're that way inclined I would definitely say go for it - the quiet sense of achievement alone will be worth it.

 

[stuart45]

Being painfully slow isn't such a bad thing for DIY. The problem for a lot of pros in the building trade is that on a lot of jobs there's more emphasis put on speed provided the minimum quality is met. It means that a lot of tradesmen struggle to adapt their methods when working on private properties for their own customers. My trade in particular is one where speed is a key issue in keeping your job.
Good point about the tools as well. I remember a friend complaining about a high price for repointing his house was, and asked me for a few tips on DIY. I told him where to get some really good jointing irons, but he baulked at the price and got some cheap ones from B&Q. The job ended up looking a bit rough. Partly because of his inexperience, but also because of the tools. He was saving himself a few thousand in labour, so could have spent £100 on tools, instead of £10 on scrap metal. It's like giving Ronnie O'Sullivan a broom handle as a cue and expect him to win the world championship.

 

[phillc]

I remade all of mine using hand tools, mostly sashes and a Victorian casement. You can go a long way with a set of chisels from Screwfix (and a good strop/stones to sharpen), some saws (including a little one) a plane and a plough plane. I just prefer hand tools.

Ok, I admit it, I got out the palm router to do glazing mouldings.

It's super doable. The bigger question is whether you enjoy it.

Histoglass (no affiliation) do historic glass, so you can get rolled or drawn looks from them.

The only other thing I would add: Make sure you know how your window is put together before you starting hacking bits out of it. Casements less so, but sashes come with quite a lot of reasons for being made *like that* and if you don't reproduce it properly, you end up coming unstuck.