Painting a sash window...

[Adam]

Hi All,

Yet more advice needed, I'm afraid, for the bumbling DIY newbies...

We're about to renovate the sash window in the room we've chosen to do first, and I wanted to ask some questions and solicite some advice...

I've done a fair bit of reading, both of the posts to uk.d-i-y and websites such as sash-style, but there doesn't seem to be much information about painting. We'd like to use a water-based paint if possible, but I suspect this won't be a very good solution for the exterior surfaces - are there any water-based paints that would do?

Part of the reason that we're gong for a full-on removal of the sashes and renovation/repaint is that the paint on the outer cill started flaking pretty much as soon as I touched it, and has come off in large chunks. The wood underneath looks damp, but actually feels OK and gives only a little to the corner of a stripping knife (pretty much exactly as I'd expect any wood to). Will it be OK to just paint over, or will I need to treat it somehow?

The current window has a hinging system in place, similar to the 'Simplex' system outlined on the Mighton website, and I'd like to renovate that too, if possible. I think the hinges and fittings are all brass (consists of two hinges, to screws in the sash frame, a thumbscrew to release the RHS staff bead and a 'clutch' for the sash cord) - what's the easiest way to strip the over-enthusiastic painting off them?

Although I've got a hundred more questions, I'll keep it to that for the moment!

Thanks for any help - Adam...

[fred]

In article , Adam writes

I've not got on well with water based paints in this role. When fully renovating sliding sash windows I've taken out the sashes, burnt off the old paint with a heat gun (not near the glass :), sanded the crust down to bare wood and painted on two coats of microporous paint (no primer!). The finish is superb and is breathable so it lasts a long time. An example of this type is International brand Ranch Paint. The drawback is that the sashes will be out for at least 2days to let both coats dry fully 16hrs each + then some but it is worth it. I block off the opening with a board while this is going on.. Also rub a candle down the mating face of sash & parting bead to reduce sticking.

You could really do with drying this out, but I reckon that is not going to happen. Suggest you take it back to bare wood then apply one coat only of Ranch Paint. That will hopefully stop further moisture getting in but may let moisture from the wood breath out. Don't be surprised if this is too much for the paint & the moisture causes it to fail prematurely, just byte the bullet & repeat the cycle. Hopefully it will be ok after a couple of iterations, then apply 2 coats of same. btw; I suppose you could give the bare wood a blast with a fan heater for a few hours before painting, but I think that will only remove moisture near the surface, and deep seated stuff will surface later, but it wouldn't hurt.

Don't have much time for those systems as I can clean the windows by sliding them one over the other & sitting on the window ledge (if you can picture that). The hinging systems IMO are just extra places for draughts to get in. I make mine easy to remove by securing the staff beads with brass screws and screw cups, 5mins to remove, but I don't really have a need to. If you want to keep them then just soak in paint stripper to recover former glory but def replace the staff (& parting) beads, they are dead cheap & can be got from Jewsons and the like. Replacing these make the windows look like new.

Your next question is "How do I draughtproof sash windows" and I claim my 5 pounds :-)

HTH

[Adam]

"stuart noble" >and renovation/repaint is that the paint on the outer cill started

Thanks Stuart, I'll have a look down at Halfords for this. I assume this just sits on top of the wood - will the damp be able to escape? What paint would be best for the resin surface?

Cheers - Adam...

[stuart noble]

No, it penetrates. Very thin in consistency and takes several hours to cure, especially in cool weather. You end up with a "wet" look but no film on the surface.

The idea is that the damp won't get in to start with. This stuff really does impregnate old wood and turn it into a semi plastic but, overpainted, it looks exactly like wood. Ronseal used to market it as "wood hardener" at some ridiculous price.

Any paint takes well. I used water based primer and an oil based topcoat. You'll notice the difference in applying it when there is no suction from the wood. The danger is that it makes the untreated areas look drab by comparison.

[Adam]

Thanks for the fast response, Fred...

It does seem to be. I tried prodding it with the corner of a stripping knife, and it *appears* to be sound to. It just has that darkened, almost grey look that wet wood takes on...

in our windows is around 12mm wide (measured fairly crudely - I'm buying some decent calipers tonight) and nearly 14mm wide at the base

- although if it's been as well smothered with paint as the rest of the window, this may translate to only around 12mm! I guess this means the slot in which it sits is around 12mm wide too, and the requirement for the might bead is a slot 8.5mm wide.

The big advantage that stands out with the ifpsl stuff is that they supply a carrier for their parting bead, which can be screwed into the slot left by the old parting bead. This may be much easier than using mastic or similar if the slot is too wide (as it seems to be with our windows).

Do you have any experience with ifpsl? Could they get the stuff to us in time (if you get to see my message in time, also!)? - Mighton at least will promise next day delivery...

No, sorry mate. Besides, any spare fivers are all already earmarked - it's an expensive business, this DIY lark!!

Thanks - I'll post results when it's done.

Cheers - Adam...

[stuart noble]

That looks a very useful product. One of the major probs with renovating sliding sashes is that if you strip all the paint off the top one you end up with a big gap between the parting bead and the outside edge of the box. Short of moving the groove or thickening the exposed part of the bead, there ain't a lot you can do except put up with the rattles and draughts. I have my doubts about the top and bottom seals. All the flexi polymer things I've tried have ended up permanently flattened when kept under pressure for weeks at a time in the winter. IME the only thing guaranteed to keep its springiness is a hollow silicone bead (can't remember who makes them) but the slot to take it can't be routed into existing frames. I think if you solve the parting bead problem and the staff beads on the inside are carefully positioned you can eliminate most of the draughts and rattles. Also, too many retro fit seals on old windows look a bit naff IMO.