Sash windows, repair don't replace!

[Dumsey]

Great, thank you. I think I need to replace the front threshold so I will get some to help bed in the new wood. I’ve never done anything like that before but this thread is giving me the confidence to give it a go

 

[Feltwell]

So, onto preparing the sashes. I like to work outside with a router, as there's so much mess generated, and there's always the problem of how to hold the sashes.

For laying them flat I have a good cheapskate option for a work table - an old pallet sat on a couple of saw horses, with a bit of ply or OSB screwed to the top. It works a treat - the pallet means you can always clamp things down to it round the edges, and having a bit of weight to it keeps it steady. Handy to screw bits of wood to the top to act as stops to push the sash against as well. I keep this old pallet round the back of garage , it get used a surprising amount, I like working outside!



If you're needing to run a router down the edge of the sash then 2 Workmates or similar is the best way to support it, on a couple of battens on the ground:-



Tomato plants and numerous kids toys and other junk are optional!

First off, choose how you want to attach the sash cord to your sash. You can of course just pin the cord on in the same way it was originally, but it's a mighty fiddly job to do that when your sash goes back in - definitely a 2 person job. Mighton do a simple product I quite like called the Grabba:-



It goes on the side of the sash, but you do have to rout out a bit of the old cord groove wider & deeper for it:-



When you come to hang the sash back in the window, the cord just threads through the Grabba and it clamps it tight - makes adjusting the cord to length very easy, and makes taking sashes in and out an easy 1-person job.

These only work though if you're happy to use modern Nylon sash cord - which doesn't stretch to any great degree and doesn't rot, both of which the original waxed cotton cord did. This is nylon cord:-

https://www.mightonproducts.com/6mm-sash-cord-20m-roll

If you can't live with the aesthetics of that then you'll need to pin the cord when you put the sashes back in the frame. Another option is to switch to chains, never tried that myself but another user on here was a great proponent of them.

The sashes themselves will be draftproofed on the vertical sides by the beads that you'll need to buy, but to complete the job fully you'll need to fit weather stripping to the top of the top sash, the meeting rail and optionally to the bottom of the bottom sash.

There are lots of different options for weather stripping - look at the websites for Mightons and Reddiseals and you'll see them. My personal choice for the top of the top sash, to seal it against the frame, is to rout a 2.5mm groove and fit a bubble seal:-



There are lots of different sorts of bubble seals from both Mightons and Reddiseals, I use Reddiseals usually. An offset leg one like I show above enables you to position the bubble near to the inside edge of the sash, minimising the gap between that and the weatherstripping in your parting bead that will seal the edges.

If you didn't want to use a router then you could just a fit a self adhesive foam seal - won't last as long but will do the job.

I like to fit a bubble seal to the bottom of the bottom sash as well, near the outside. It's not strictly necessary as there will be a seal from the staff bead there, but it helps stop water blowing under the bottom of the bottom sash.

The meeting rail - I like to fit a brush seal to the outside of the top rail of the bottom sash - that way it's hidden from the inside at all times, and only visible from the outside when the window is open. I rout a plain 8mm groove and fit a self adhesive pile carrier:-



I used to fit a carrier with a leg which gripped into the timber, thinking that self-adhesive wouldn't last - but then I realised that when you paint over the pile carrier, the paint seals it in very well to it's groove. In this pile carrier I fit brush seal, usually to suit a 5-8mm size, after it's been painted.

Again if you didn't want to rout a groove you can get self adhesive brush pile, I'm not sure how long it would last with a window pushing it sideways as it's open and closed though. You could also just leave these seal out completely - seems a shame though when you're going to all the effort for the rest of the window.

The last bit of preparation prior to glazing and painting is to check the fit of your sashes back in your window. The seals do push the sashes in a little, so you may need to take a little off the bottom of the bottom sash or the top of the top - which is simpler, as it's square. Ideally of course you do this before you machine the grooves, experience will tell you what tolerance to allow for whatever seals you intend to use. You want to make it so the 2 surfaces in the middle that your catch goes across are level with each other.

If the sashes are too small then the easiest way to go is to cut the sash back before gluing a strip of timber on. The edge of the sash is rarely square, cutting it back gives you a good square edge, stops you having to use too thin a piece of timber and it enables you to correct any side-to-side difference - so for example if you need to add 2mm on one side and 5mm on the other to make your window align properly, cut back 8mm and 5mm respectively and add a 10mm piece of wood.

I've had to do that here - more clamps than Miss Whiplash! :shock: Probably overkill but does no harm whilst the glue goes off...….



Next up, glazing.

 

[Feltwell]

I’ve never done anything like that before but this thread is giving me the confidence to give it a go

Great, that was the idea! Please don't think I'm proclaiming myself to be an expert though, I'm not, this is just where I've arrived at through experience over time and some trial and error of what works best for me. There is definitely more then one way to do this, others may work differently.

 

[Flyfisher]

First off, choose how you want to attach the sash cord to your sash. You can of course just pin the cord on in the same way it was originally, but it's a mighty fiddly job to do that when your sash goes back in - definitely a 2 person job. Mighton do a simple product I quite like called the Grabba:-

Exactly the sort of thing found on small sailing boats - available in many different sizes from all good chandlers. I'd never have thought of using then in a sash window.
https://www.marinesuperstore.com/deck-hardware/cleats-and-fairleads/holt-clam-cleat-junior-cl203-r

 

[CliffordPope]

Another suggestion for replacing a rotten cill is to cast one in-situ in cement. Suitably shuttered, with the correct slope and rebate profiles, and painted, it is indistinguishable from a wooden one.

I offer this slightly tongue in cheek. I have done it once when I just couldn't face the fag of making and fitting a proper one.
The only person who ever noticed the difference was an aerial fitter who tried to drill through it.

 

[Feltwell]

Exactly the sort of thing found on small sailing boats

Ahh, didn't know that, being strictly a landlubber! (Shropshire not being noted for it's coastal scenery!). I'm pleased to say that Mightons may have ripped off the idea but they're not ripping off the customers, at £2.10+VAT for a pack of 4.

The only person who ever noticed the difference was an aerial fitter who tried to drill through it.

Serves him right! :twisted: I hate exposed cables, so of course I bought a house that (was) full of them. I've been gradually getting rid of them. A particular favourite was the aerial cable from the (broken) aerial on the chimney, running down over the roof tiles, down the wall of the house (but not tacked to it - oh no, just swinging gently in the breeze, totally unattached right the way back up to the chimney), then in through a window frame ( :evil: ) before waving about behind the telly.

 

[Zebra]

more clamps than Miss Whiplash!

:lol: :lol: :lol:

 

[CliffordPope]

Serves him right! :twisted: I hate exposed cables, so of course I bought a house that (was) full of them. I've been gradually getting rid of them.

The aerial is fixed to the lower end of the gable bargeboard. I suppose it could have been jiggled inside the corner of the sloping roof up into the attic, but it would then have had to be run inside the house down the walls and along a landing and through two ceilings, so it would have been exposed somewhere. An alternative to drilling through what would normally have been a few inches of wooden frame would have been through two feet of stone.

 

[Feltwell]

So, onto glazing......…

But first - the importance of getting a good relationship going with joinery shop! One nice bit of oak cill and some hardwood roll for a gable end timberwork repair that I picked up today - always easiest to cut a bit of the old out and take it in with you for them to copy, with written on it what you want!



So, glazing. If you need new glass I strongly recommend that you take the sash into the glaziers with you, rather than relying on measurements. Rebates can be narrow and sashes frequently aren't quite square. If you wanted to use putty, any decent glazier will also putty the glass in for you, though it's not a difficult job.

If you're replacing the glass you do want the sash to be in balance side to side, so if you've more than one pane wide make sure the thickness is the same in all of them. Modern float glass is alas soulless stuff, but is widely available and it's cheap. "Wobbly" glass can be obtained, but it's much harder to do so and it's much more expensive.

One specialist is Tatra https://www.tatra-glass.co.uk/restoration-glass/. There were different types of glass used in years gone by, if you're looking at a Victorian sash then it's most likely to have been machine-drawn glass. My house had better quality glass downstairs, in the "posh" rooms, than it did upstairs. Ironically the posh stuff is the flat stuff, i.e. quite close in appearance to float glass! The cheap "wobbly" stuff upstairs is what you'd now pay much, much more for.

I'm afraid I've never had the time to get restoration glass in, so I save as much original as I can and have used float elsewhere

If you've got windows going close to the ground, you may want to consider toughened or laminated glass. Toughened is heat treated so if it breaks it shatters into thousands of tiny pieces that are only likely to cause minor cuts, rather than big shards that normal glass breaks into which can do much more damage. Glaziers don't stock it - they cut normal glass to size then usually send it away to be toughened - you can't cut toughened glass. The glass is processed in a special machine which heats it very high then rapidly cools it with blasts of chilled air. Laminated glass is 2 sheets of thin glass with a plastic sheet in between that they are bonded to, if it breaks the glass stays bonded to the inner sheet. Laminated is more secure if security is a concern.

If you're reusing the original glass, clean all the old paint and putty off. I hate doing this job! The only scraper that I've ever found that is any good is this one, which takes disposable blades rather like razor blades:-

https://www.toolstation.com/axus-retractable-window-scraper/p54199

You'll go through *loads* of blades - I can use a pack of 10 blades on one pair of sashes no problem! Glass is quite easy to scratch, wetting it first definitely helps. Your other option is to use chemical paint stripper of course, easier but messier.

So, to put the glass back in. Your first choice is what to use - linseed putty, a modern sealant, or beading.

Linseed putty is without doubt the "period" way of doing it. Made from powdered chalk and linseed oil, it's cheap and easy to use but does have some drawbacks - most notably, that it takes forever to go off and you can't paint straight over it with water based paints - you've either got to use oil based paint (which personally I'm not much of fan of) or you have to prime over it with an oil based primer to seal it before you use water based paint. Whichever, you've usually got to leave it a couple of weeks after puttying before you can paint it - and that means painting in situ, whereas I find it easier to paint on the bench. The other disadvantage is as you've seen it goes rock hard eventually and is prone to eventual failure through cracking.

If you want to use linseed putty then I recommend getting a tub from a glaziers, not a DIY store. It's best when fresh and not many people use it any more, the DIY store stuff is exactly the same but more likely to have been sat around for ages - Glaziers will have a quicker turnover.

It's best to prime the rebates first with raw linseed oil. Then you need to knead your putty - work it like you would bread dough - then you put in your bedding putty, put your glass in and squidge it down so that the bedding putty is well settled in, and trim the excess off. The exact thickness doesn't really matter, 1-2mm is fine. The you need to secure the glass with some "glazing sprigs" - little bits of metal to embed in the timber to hold the glass whilst the putty goes off, which remember takes weeks.

You can get the traditional triangular brads, but I found "push points" to be easier. Don't bother with the special tool they sell to put them in, a large screwdriver or thick scraper blade works just as well.

https://www.amazon.co.uk/Fletcher-G...101340&sprefix=glaziers+push+p,aps,146&sr=8-2

Some folks just use small galvanised nails, I broke the glass using them once so stick to push points! More surface area against the glass.

You then put your facing putty in and shape it with a filling knife to throw water off. You want the line of the putty on the glass to the be the same as the viewing line from the inside, i.e. the top of the rebate, so you're not looking at the back of the putty through the glass from the inside.

Your other alternative, which I now use, is to use a modern putty-replacement sealant. Why?

- You can paint straight over it with water based paint
- It goes off and you can paint over it after only a couple of hours
- It's permanently flexible and I believe will last longer than linseed
- No need to prime the rebate with linseed oil, no need to use glazing sprigs - it's sticky enough to hold the glass in safely whilst it's going off
- You should be able to cut it out with a sharp knife in future if necessary
- Done well it's indistinguishable from putty

Disadvantages

- More expensive
- Harder to get a good finish, especially at the end of a run

If you do go down this route I heartily recommend a "Palu Tooling Block" - see the second half of this video, the white sealant is glazing sealant

https://www.youtube.com/watch?v=regl5P6uUQ4

https://www.sealantsonline.co.uk/Products/0044005c/MIS6586

I expect you could use it with linseed putty as well.

For sealant, I tried a couple of different types and found "RepairCare Dry Seal MP" to be the best.

https://www.sealantsonline.co.uk/Products/00440078/WIN7506

The last option to hold glass in is timber beading. Usually you'd only use this if you took timber beading out, but if you want to down this route then most DIY sheds carry it, Wickes round here certainly do. I'd definitely go for hardwood. Personally I don't think it looks right as a putty replacement, and anyway the rebate lines are a bit too rough on my windows to consider it!

So, the glass is in, next job is the sash weights. You can use bathroom scales - they're accurate enough. Weigh your top sash and your bottom sash, you want the 2 weights for the top sash to be in total around 1/2 lb to 1lb heavier than the sash itself, and the for bottom sash you want them to be 1/2 lb to 1lb lighter than the sash. Why? So if the sash tries to move in high winds, it will tend to self-close rather than try to open and cause drafts.

If your sash weights are too light you can buy "make weights" from Mightons or Reddiseals that thread onto the sash cord and sit above the original weight - or if you've got some lead weight with a hole through the middle, you can cut your own.

One thing you need to avoid on reassembly is the weights "hanging up" on each other, i.e. the weight for the top sash catching on the weight for the bottom sash, or vice versa, as they pass each other. Several ways to avoid this:-

"Feathers" - you may have thin strips of wood floating loose in the sash box - great if you have, these work really well. Just make sure they are between the weights when you reinstall them. You can't really add feathers though, I did it once but only because I was cutting a lot of the front of the sash box away to replace rotten wood on a bay window.

If you're buying new weights, you'll always have to check if the sash box is large enough to take them but try to go for round weights rather than square, I find square weights more prone to catching.

You can also get conical make weights that help the weights to bounce off each other rather than catch, and of course you can shape the top or bottom of weights. I had some lead weights that I couldn't afford to cut anything off, I needed the weight, so I shaped the top and bottom with a hammer - crude but it worked!

Next episode, choosing the staff and parting beads and painting.

 

[Feltwell]

So, getting towards the end now. Next bit is what staff and parting beads you are going to use. There are two main suppliers - Mightons and Reddiseals, both do a variety of beads in a variety of materials. My personal advice would be stick to timber - I tried a wood composite bead and I thought it was awful, looked OK once in but was like Weetabix in texture and very easily damaged. The beads don't tend to rot - the staff bead is all internal anyway, the parting bead I've never found has a problem - plus I finish the parting bead about 3mm short of the cill deliberately so no water can ever get trapped behind it. Hence I don't see the need to pay extra for materials like Accoya, the basic timber ones are fine.

I would however pay for the pre-primered ones - they're not much extra and are a useful timesaver.

https://www.reddiseals.com/product-category/sash-window/beading/
https://www.mightonproducts.com/pro...tripping-beads/timber-staff-and-parting-beads

Plastic beads - no, just no. They look horrible and there's no need to use them. The *only* exception is if you really need a parting bead with weatherpile on both sides, then you have to use plastic, Reddiseals do one. I have one particular arched window where these do work better as there is so little parting bead for the window to run against.

The Reddiseals timber beads come with a nylon insert to hold the weatherpile, Mightons do one where there is no insert, straight to wood. Does it make a lot of difference? I don't think so, if anything the nylon insert will be more durable for future weatherpile changes. I use the Reddiseals ones.

So, first off, the parting bead. Measure the thickness of your old ones - most are 8mm, a few are 7mm, you can get both. There is also a much chunkier Scottish bead at 14mm, available only from Reddiseals. If you have another odd size then you may have a problem - I had 1 window here that for some reason had 9mm parting bead. Reddiseals do a plastic U shaped channel that is very handy if your parting bead groove is damaged or an odd size - you rout it out to 10mm wide and a bit deeper than usual, pop the self adhesive channel in and it brings the groove back down to a standard 8mm size - it's invisible once painted in.

Width of parting bead - most are 25mm, but you can get 28mm if your sashes are a little narrow for the box or are damaged/worn on the edge. Don't forget the brush seal will be running a bit further to the edge, so the 28mm pushes it out onto the face of the sash a little more. You might need to trim the meeting rail protusion on the bottom sash back a little to accommodate this.

The parting bead needs to be cut, with a joint hidden behind the meeting rail - so the weatherstrip on the top part of the bead faces outside, and on the bottom part faces inside.

What seal to use - I usually use brush pile weatherstrip on the parting beads. I have to honest that I'm in 2 minds as to if a different seal would be better, more on that in a moment. The brush seal has a central fin as well, so is effective at stopping drafts and rattles and enables the sash to slide very smoothly. The smallest 5.5mm size (to suit 1.5-2.5mm gaps) is right for most sashes. The larger 8.5mm size tends to be needed for the carrier on the meeting rail.

https://www.reddiseals.com/product/reddipile-draughtproofing/

Why am I in 2 minds? Well, you have to be very careful to keep paint away from brush pile when repainting in future, they do tend to squish a bit after a while and they do tend to go a bit grubby. The alternative is a Schlegel foam-cored seal

https://www.reddiseals.com/product/schlegel-ql48650/

I use these on the staff beads - they do seem to stay cleaner than the brush pile. I've yet to experiment with using them on the parting beads as well, the brush pile enables the window to slide so well. Whichever seal you use, do put a little bit of superglue on both ends when you insert them into the bead, otherwise they will keep trying to slide out - only a little bit mind, you want to be able to change them in the future.

Staff bead - a similar story to the parting bead, but you may want to consider going up a size. For example, here the original beads were 15mm wide - and you can buy 20x15 beads, the same size, with pile carriers in. But going up a size to 20x20mm puts the bead further onto the face of the sash, less likelihood of the sash being able to pop off the edge of weatherpile, the sash can always move side to side to a degree.

 

[Feltwell]

Painting. I much prefer to paint a sash window prior to reassembly, much easier. Lots of threads on the forum about paint choice, I'm now a firm convert to Bedec MSP.

First choice is how many colours to have. Generally you'd have 1 for inside and 1 for outside, but personally I think it looks good and more "period" if the sashes are a contrasting colour externally to the box frame, so 3 colours overall. Personal choice of course!

So - I paint the outside of the sashes one colour, and the inside a different one. You should overlap the paint onto the glass by 2-3mm to give a seal - either cut the paint in or cheat and use masking tape, the "frog tape" brand works well at preventing paint bleeding under the edges of the tape. Do not paint the vertical sides of the sash - if you do your sash will stick terribly! There's no need to paint them, they're protected enough from the weather, mine have survived 120 years as bare wood!

Where to do the colour change - well, as I fit a seal to the top and bottom of the sashes, I use the routed groove as a handy point to switch. The bottom of the top sash has to be the outside colour. The top of the bottom sash has to be the inside colour.

When you paint the bottom sash, you will paint over the pile carrier you routed in for the meeting rail. No need to avoid it - the paint seals it into the groove and helps hide it - BUT - when you've finished painting any carrier always pull a scrap inch or so of weatherpile through the carrier whilst the paint is still wet - it spreads any paint out which has got into it and which otherwise makes it a nightmare to insert the weatherpile when the paint is dry. I found this out the hard way!

For the box sash, on the sides I paint all that is inside of the parting bead groove the internal colour, all that is outside the external colour. I paint the entire cill the external colour - the colour change outside to inside then happening under the staff bead. The top of the sash I paint all in the internal colour, the colour change happening at the outside edge, like this:-



Beads - the top half of the parting bead is in the internal colour, the bottom half is in the external colour. Try not to paint all the way to the bottom of the bead - stop just short - makes them much easier to get in the groove. Staff bead all in the internal colour. Don't forget to run a bit of scrap weatherpile, only needs to be an inch or two, through the carrier as soon as you've painted it, if you don't you will regret it!

Hardware. You may or may not need to replace your sash pulleys - mine were all worn out so all got changed. Mightons and Reddiseals only do shiny shiny ones, I'm not a fan. Not knowing any better I used some lacquered brass Mighton ones on my first window - they run beautifully smoothly, but the lacquer went manky and tatty looking quite quickly round the edges. They also do ones with plastic pulley wheels, my neighbour fitted them - not nice.

I've since found Broughtons, who do many nice things that can empty your wallet, including nicely aged sash window hardware - you can see their sash pulleys in the picture above. One thing to watch though is they aren't very square, every one is a little different - they're a bit bigger than my old pulleys, so I label every one and cut the sash box to suit each one. Lots of lovely period-appropriate stuff at Broughtons, including shiny if that is your preference.

https://www.broughtons.com/store/department/55/sash-window-fittings/

Reassembly - at last!

You may need a "mouse" to thread the sash cord through the pullies and down to the bottom of the box - an old screw tied to bit of string works fine, then use the string to tie to the sash cord to pull it through. Put the weights back in the sash box, remembering that the "feathers" - if you have them, a thin strip of wood floating loose in the sash box - go between the weights. You'll probably have to put one weight in, tie it to the cord, and haul it up a bit to give enough room to get the second weight in - mind your fingers! If you're using nylon sash cord, heat the cut ends with a cigarette lighter to melt them and stop them fraying.

Put all 4 weights in, giving yourself plenty of sash cord spare, it's only cheap! Pull them up and down and make sure they don't catch or foul each other before you put the sash pocket covers back in, then check them again - much better to find a problem at this stage.

Next, install the top sash. The weights should be a few inches off the bottom of the sash box when the sash is at the top of it's travel. If you fitted the "Grabba" I mentioned earlier, this is a very easy job and easy to adjust the cord length. If you didn't and you need to pin the cord, make sure you've got some help, it's a fiddly job. Try and leave a couple of inches of cord spare if you can, and again heat the ends to stop fraying, you might just need to shape them a bit with your fingers when they're hot, otherwise the end end "mushrooms" and won't go through the Grabba.

Next, your parting beads go back in - remember, inside colour at the top with weatherpile facing outside, outside colour at the bottom with weatherpile facing into the room! The beads should just push into the grooves, might need a block of scrap wood and a hammer to persuade them in but be gentle. You shouldn't need to pin them into the grooves - the paint will soon stick them in place, pins just make them a pig to get back out again in future without breaking them. Check your top sash slides up and down freely and the weatherpile at the top makes contact - if not you'll need to change it for the next size up - I've never needed to.

Next, the bottom sash goes in, same way as the top one except now the weights need to be a few inches short of the pulleys when the sash is at the bottom of it's travel.

Finally, your staff beads that you've nicely mitred to size go in. Don't make them too tight to the bottom sash, so long as the seals on the parting and staff beads are in reasonable contact with the sash all will be good, squeeze them too much and the window will be hard to open. You can just nail the staff bead in place, but I prefer to drill it, countersink and fix it in place with raised heard brass screws - makes it so much easier to take it apart again in future if you need to. Drive a steel screw in first though, cuts a thread for the soft brass screw to follow, saves the risk of snapped off screws or mangled heads.

Put your sash lifts and catch on and you're done! Paintwork may need touching up a bit. Some prefer to run some caulk down the sides of the parting bead if the groove is a bit rough at the edges, and round the sash pocket cover - I don't tend to worry. For the first month you should move both sashes every day, stop them sticking. Silicone spray is fantastic stuff if they need a bit of lubrication, I've used it after a couple of weeks, it stops the paint sticking and I've never had a problem with it reacting with the paint.

So there you go, hopefully you can now stand back and admire your lovingly restored window that glides up and down smoothly, doesn't rattle at all and hardly lets any draft in at all!

For another view, this article from this very website is worth a read:-

https://www.periodproperty.co.uk/ppuk_discovering_article_041.shtml

As I've said a couple of times, this is just my way of doing it and what I've found works for me, it's not the "right" way - others will do some things a bit differently. I hope it's useful though and inspires someone to save their sash windows - they really are almost infinitely repairable, a very tatty looking sash can be brought back to great condition with just a bit of love and attention, and will be carrying on long long after the plastic UPVC cr@p is in landfill.

Phew - that was much longer than intended, is anyone still awake? :wink:

 

[overlander matt]

Great posts Feltwell. I learned a lot from your earlier post about the bay window restoration and so has our joiner (who has done a few working for the National Trust). Together we have now restored all but one of the 16 sash windows in the past 12 months. Your instructions are very clear and cover everything for anyone coming to sash window repairs in future.

Thanks for your efforts and wise words!

Matt

 

[RBailey]

Great post and very useful information.

Thanks for taking the time making the effort.

Thanks,
Richard B.

 

[CliffordPope]

the top half of the parting bead is in the internal colour, the bottom half is in the external colour.

But doesn't that mean that when the windows are shut, from the outside you see the inside colour visible as a stripe running down the side of the lower sash? That would look a bit odd?

My principle is to paint the whole of the inside face of the bead in the inside colour, and the whole of the outside in the outside colour.
That way you never get a stripe of the "wrong" colour showing whether the sashes are open or shut.

I agree that complicates painting the edge. The edge of the upper section has to be in the inside colour, but the edge of the lower section has to be in the outside colour, or else again you see a thin line of the wrong colour.


Some painting problems are insoluble. Imagine a simple plank door with horizontal planks holding it together, opening into the side with the horizontal planks. (As you would with a back door, opening inwards)
Viewed from the outside, with the door open, at the hinge side you get a view of the edge of the door plus the ends of the horizontals.
So you paint them in the outside colour.
But then with the door shut, viewed from the inside, you get a thin line with three ends visible painted in the outside colour.
I don't think there is an answer in that situation except to chose a different colour scheme.

 

[Feltwell]

the top half of the parting bead is in the internal colour, the bottom half is in the external colour.

But doesn't that mean that when the windows are shut, from the outside you see the inside colour visible as a stripe running down the side of the lower sash? That would look a bit odd?

No, because the lower bead is in the outside colour. I don't think there is a right or wrong, but I do think what is best for each window depends to an extent on the dimensions of the window in question. Usually - but maybe not always - the parting bead is a lot narrower than the width of the side of the sash, so you never see the opposing colour. Indeed, if you painted the bead 2 colours I'd be concerned you'd see the other colour on the edge. This is how it turns out with the beads in different colours top & bottom:-

But as I say, I really don't think there is a right or wrong way to do it, all involve a compromise somewhere!

Thanks for the positive comments folks. I've definitely learnt through trial and error since doing my first window a good few years back, hopefully this will encourage others to take the plunge and have a go!

 

[CliffordPope]

Lovely windows, very helpful article - many thanks.

I think I'm complicating it by having three colours - by inside I mean the woodwork colour inside the room, including the sashes and the outer woodwork of the embrasure panels.
By outside I mean the outside colour of the sashes, but these are not in the same colour as that of the frame of the window and the face of the sash boxes.
Thus, I have just repainted an upstairs landing window. The landing woodwork colour is dark torquoise blue, which includes the inside of the sashes. The outside sash colour of all the windows is white, and the outside window frame is black. The normally exposed "track" of the outer sash is also white. I think it looks odd having the black intruding inwards over the inner face of the frame, because that spoils the neat rectangular black framing of the white sashes, so the inside-facing edge of the outer beading is white, with only the front and edges black.

As a further complication access is only normally possible from the inside because the window overlooks a pitched roof porch, so access is not possible by a simple ladder, only by scaffolding built over the porch. So I have recently been sitting outside on the ledge with my legs sticking inside, moving sashes up and down from the outside to expose and reach the various parts for painting. This has had to done in stages to allow paint to dry before sliding a sash over it. I have managed it without knocking over the paint pot balanced on the sloping window ledge, nor dropping either of the two sizes of brush needed.

I could see from the strange variety of colours chosen over the years by previous owners that they have had different ideas as to which schemes look best. The sashes had clearly always been painted in situ, so there was a kind no-mans-land in the middle that was mostly unpaintable neatly. Most of the windows had simply been long-painted shut, especially the lower sashes which slide but do not have sash weights, just handy sticks for propping them open.
Almost invariably they had all forgotten the two facing edges where the sashes overlap, revealed when I finally got the windows open and exposed an ugly line of long-dead flies and spiders preserved in paint that had run down the gap.

Thirty years ago I repaired all the sashes and painted them before reassembling, but now for routine re-painting I do them in-situ using a variety of brushes and cardboard masks, and half clothes pegs to keep the sash over to one side while painting the other face and the beading it runs in.

Despite all the trouble however I would rather live in a cold house with draughty rattly fiddly original sashes and old glass than a warm snug insulated house with horrible plastic windows.

 

[Feltwell]

All sounds good! I'm lucky in that all bar one of my sashes is relatively accessible - mind you that one is a pig, 3 floors up and it's arch topped so it doesn't open as far as a "normal" rectangular window. So it's either use my scaffold tower, or take it apart to decorate from the inside.

Despite all the trouble however I would rather live in a cold house with draughty rattly fiddly original sashes and old glass than a warm snug insulated house with horrible plastic windows.

There is of course the halfway option if you can stand to change the beads. Honestly, you wouldn't believe the difference that good weatherstripping built into the beads makes - the bay window above used to be a pig to open, plus it was very drafty and rattly, I used to stuff kitchen roll round the central opening window in winter! Now the sashes just glide up & down, no rattles, very minimal drafts (sash pulleys are the only offender! I figure a little bit of ventilation is a good thing).

 

[BDJ]

Timber moves - that joint will open up at some point and let in lots of rainwater, leading to the above. So many people, including carpenters who should know much better, take the lazy option and chop the old cill out there, leaving the rotten remains under the boxes.

Hi Feltwell, I'm new to this forum but am loving your sash window repair posts. Very informative. I have exactly the water ingress problem that you describe regarding window cills not having been properly installed underneath the sides of the boxes. However, I'm wondering how you can get a new cill under the sides without removing the sides, or part of them..? Any help appreciated. Thanks

 

[Feltwell]

Glad you like this old post!

The sash has a box either side for the weights, sat behind the exposed outer brickwork - and that box is of course also a bit narrower than the inner, hidden brickwork it sits within. Your cill only has to go under the exposed, outer edge of the sash box - so once the old piece of cill is cut out, the new piece is slipped far into one side, swung in past the outer brickwork then slid back across. So long as it goes an inch or so under the exposed box edge on both sides and is behnd the facing brickwork edge it'll be fine. I always cut them to be as long as possible, but it's not really necessary.

It can sit snugly under the sides, you might need to trim them a little bit in-situ to fit, an oscillating multi-tool is perfect for this. However, if the cill has gone there is a high chance the bottom of the side will be rotten as well and need a new piece splicing in - the end grain at the bottom of the side wicks up the water if it gets in. It's not difficult to splice a new bit in with epoxy after your cill has gone in, it helps that you've some access through the sash pocket.

I trust that makes sense, if not let me know.

 

[BDJ]

Ok, got it. Thanks a lot.