Time to repaint the sash windows

[overlander matt]

It's 5 years since we restored the sash windows on our Georgian house following the guidance on this site from Feltwell and others. All windows were taken back to bare wood. Accoya sills were fitted to nearly all with Repair care resin used for the repair work. A small number of replacement sashes were fitted. We fitted 3 new hardwood sash windows. Bedec MSP was the chosen paint.

As part of a larger project, I feel we didn't give the job quite as much care and attention as we might if it was just a one off with more time to devote. That said it took me and our joiner approximately 5 days to repair and repaint each window.

5 years on and I think I need to get the paint out... The Bedec MSP has been OK, no complaints but I wonder how others have fared with this paint. Would you use it again?

I've attached a few photos showing the current condition of a couple of windows. As I've not done any repainting since the renovation, I wonder what you would advise... A quick rub down and recoat without taking anything apart? Extra coats on the sills look necessary.

What about any cracks? The repair care has cracked in places and I wonder whether I need to do anything other than just painting?

I never really did anything to fill the gap between the brickwork and the recessed sash windows. Most of the windows were more flush with the brickwork but some newer additions sat behind the outer skin of bricks. I must admit to using some caulk on some and lime mortar for the wider gaps. I never finished the job and would be keen to know the best approach.

Thanks in advance for any guidance offered.

Matt

 

[fernicarry]

Hi Matt, good to see you are still around, hope things are progressing nicely. External woodwork, the gift that keeps on giving...

I have to admit I've given up on MSP for external use. It deteriorated very quickly on my sills and parting beads to the point it needed titivating practically every summer. I'm a bit of an extreme case being very exposed, but I've now done some windows with Demidekk and it seems to be holding up far better. I've since read that MSP isn't recommended for surfaces that water stands on so that would certainly match my experience.

So far as sealing round the frames I've come to the conclusion that a lot of the historic damage here can be traced back to water coming in around the window frames over a period of time so getting a good seal is essential. The tradition here is to fill the external gaps between the frame and the masonry with burnt sand mastic (after packing the gap with Daily Records obviously) but this hardens and fails after a time. What I now do is first put a bead of Soudal Acryrub in the gap, this is one case where I think modern gunks are justified, then put a fillet of burned sand mastic over that just as a decorative finish (or at least I intend to once I feel that the sills that are currently under suspicion can be trusted...).

Also, the last couple of sills I've replaced I've put expanding foam tape (not the same as gun foam!) along the bottom of the sill and up the edge as another line of defense. The foam should accommodate any unevenness and relative movement between the wood and the stone sill under it. And the one I've just done I packed under the sill from inside with lime plaster! I'm not paranoid about leaking windows...

I've got a repair on one of the back sills which I think I'll need to dig out and do a bigger repair on as its getting a bit squidgy. Ideally I should replace the sill but the repair gave me 10 years so I'll see if I can get the same again out of it. Chances are it won't be my problem by then...

Best of luck. If only it would stop raining I might get a bit of paint on my own windows...

 

[overlander matt]

Thanks Alan. That's very helpful. It is indeed an endless task and the heights involved add an extra level of pain to it.

I was hoping to have finished all the house repointing work this year and then paint the windows but that sadly hasn't happened. The timber needs some work so I'll get on with some remedial work.

I have noticed the MSP struggled on the parting beads and the new sash windows which were received already primed. I will probably try another paint when I do a more comprehensive repaint. I will need to buy a good scaffold tower as we have a wooden cornice around the house at 10m above ground level.

I've not tried the burnt sand mastic yet. Is it easy enough to apply? I'll probably be hanging out of a couple of the windows. I'm hoping that one can use other papers than the Daily Record to plug the gaps!

Thanks again Alan. I see you are busy there with the fireplace!

 

[fernicarry]

I've not tried the burnt sand mastic yet. Is it easy enough to apply?

It probably is once you acquire the knack. For me its like my attempts at plastering, 75% of the material ends up on the floor...

MSP struggled on the parting beads and the new sash windows which were received already primed

Yeah, that's exactly what I find. Pre-primed parting beads, the paint flakes off within a year. Sand it back to bare. repaint and it stays on... So I might be unfairly blaming MSP for the parting beads, but it still performs poorly on the sills.

Demidekk primer takes 24 to 48 hours to dry and even then its still a bit tacky. For that sort of effort it ought to be good!

 

[overlander matt]

Thanks again Alan. I've got a busy few weeks of painting coming up.

I will have to look at a scaffold tower before long. The windows should be OK accessed from inside and with a ladder but there's a large wooden cornice that runs around the edge of the roof that requires some proper kit...

 

[GrahamHowie]

Hi overlander, I've just bought a cottage and its new sash needed work. Similar condition to your photos of your sash. I used linseed putty for any cracks and its natural and not synthetic filler. Putty works well for parting beads and cracks. If you're confident and experience in applying and smoothing putty, it works well.

 

[overlander matt]

Thanks Graham. The windows aren't in bad condition but definitely need some attention over the next few weeks assuming we do get some decent weather... Do you find you need to wait long before painting with putty?

 

[noj]

Putty and oil based paint is happy together. Putty and water based paint less so...

Oil based primer and then undercoat does work before water based, but does sort of defeat the general idea.

From experience...

 

[overlander matt]

I previously used Bedec MSP - a water based paint. Given the weather and time of year, I think I'll go with another fast drying paint. I've left it a bit late in the year for oil based...

 

[Stevers]

One advantage of solvent based Zinsser AllCoat is that it can go on in lower temperatures than water based Zinsser AllCoat. I've also got some sashes to paint and I was going to use solvent based as its inevitable that I'll still be painting in October.

I've found the first coat of solvent based AllCoat (as a primer) needs a lot of thinner, and subsequent coats benefit from quite a bit of thinner to go on nicely. I've used Turps and White Spirit as thinner, the Turps smells nicer, but the smell of the Solvent based AllCoat is pretty vile and Turps doesn't mask it. The Zinsser destructions specify 10% thinner for spraying, so my thinning the paint further might be bad advice, though I don't think I'm alone in thinking that paint should soak into wood and not just sit on top of it.