Just been having a poke at my window sills…a few issues uncovered as list and pic below, any help welcome.

1. wood is rotten in the corner only, I plan to patch it, waterproof PVA in new sections….that OK?
2. big gap beneath wooden sill currently filled with expanding foam 🙄 what to fill this with…a wee strip of pine? or…
3. what mastic to fit between the wood and the stone sill – and could it fill the gap above allowing me to forego 2?
4 lots of the masonry paint came off, sometimes with damp stone underneath…do I need to prime this or just paint straight on?

Overall I want a seviceable repair at minimum cost/work…TIA

IMAG0954.jpg by alan cole, on Flickr

That barely looks rotten! No end of ways you could fix/bodge that depending on how perfect you want the final result. If it was me I would treat the rotten timber with something to stop it rotting then get some exterior wood filler and shape it. I would fill the bit in front with some ready-mix cement then paint it all over.

But I am NOT in any way a professional!

if you get that liquid wood stabiliser stuff it soaks into the wood and really makes it solid you can then just build back up with exterior polyfilla.

any of the normal frame sealants is fine.

I’d probably either leave expanding foam or if it’s kjnackered put some more in and then fill over the top with some paintable mastic.

I’d like to see a spoon introduced to the repair at some point though 😉

Sounds encouraging, ta…the wood is rotten through but only for the last inch and bottom 4″ of the bead…off to B&Q!

Barely looks rotten to me !

I used some stuff like this http://www.cuprinol.co.uk/products/ultimate_repair_wood_hardener_overview.jsp

where I could literally push my finger in to the wood like a sponge. It does an amazing job, yours doesnt look bad to be honest, or if indeed like it needs it.

The I would just put about 3 layers of primer and lots of layers of gloss. Worked a treat for me.

Slight tangent ,but ideally you need to treat the cause of the rot first.

If its just water ingress due to unprotected wood then pretty simple to remedy but to me its pointless repairing the wood if the cause of the rot is still there untreated ,it will just attack somewhere else on your frame.

Its worth investing in some decent frame sealant/mastic as some of the cheaper stuff will shrink or not even adhere that well,Sikaflex is a good brand.

Hmm upper sash frame is rotten at the bottom, hope that treatment works!

Unovolo – yes, indeed! It appears it’s all water ingress through cracked paint.

Oh noes…

IMAG0957.jpg by alan cole, on Flickr

one of the upper frames is about to lose its bottom also!

That new pic would concern me the first ones of the lintel would not.

They look like sash and cord windows, so you may find a talented joiner that can replace the bottom bit of wood. My mum got that done on one of her windows and so far it has been fine.

One of the things i mentioned to her over christmas was about an edinburgh company doing really thin double glased units that can go in very similar wooden frame to thoes curently fitted to get round the planning constraints of a listed building. I saw them on grand designs once and it just stuck.

A quick google gives these guys as the folk from the program.

a local joiner will make a new sash for ‘not much’ and then get it glazed for you.

It usually costs the same to replace a window sash as it does to repair it as a repair is labour intensive and only as good as the guy who does the job. The picture looks like wet rot and will be caused by the timber being exposed to the weather not all that serious a problem.(www.ajhilston.co.uk) I use these guys from Falkirk, very competitive and a very high standard of workmanship.I would also investigate below your window at the skirting, floor and joist ends. If you have water ingress from your window there’s a good chance you will have some problems here also. Hope this helps

As far as your mastic issue is concerned you should use a sand mastic. This will fill a much bigger gab than a polysulfate mastic and you can also paint it.Resolving your problem of the gap filled with expanding foam.

http://www.masonsmortarshop.com/traditional-burnt-sand-mastic-5-litre-tub.html

chickenman from this forum is a local joiner.

Check the gutters, as overflowing gutters or blocked down pipes are usually the reason for rotten windows, if you dont like heights ask the local window cleaner to havbe a look and for a handful of cash will clean them out for you.

cheers guys. gutters (and new roof 🙁 ) recently done…am gonna have a bash myself at the repairs I think, I’m OK at the woodwork and am time rich/cash poor ATM…the pictured on above is only rotten along a short length, the last mentioned one is fubared on the lower part of the frame, I’ll see if I can replace that part alone.

You will find it much easier to do if you can match the window profile. When i did window repairs in my youth in Edinburgh there was a good saw mill not very far from Leith that had all the types of sash bar and sill profiles common to Edinburgh.You could also try Keyline at Leith docks.Three tips i would suggest, de glaze the window before you start, the glass will be brittle from UV damage, keep the window on a flat surface and weight it down to let the glue dry and not twist and try and maintain the same shape the sash is just now as if the casement has move of the square if you make your sash square you will have a gap at the sill. Good luck.

wwaswas – you’ll need to try harder or think of something more obscure, as a spoon would obviously be used to tool the large mastic joint under the cill!

Some larger B&Q’s sell Sikaflex (look in the outside builders yard area as it’s often with the other Sika products like cement additives etc)

Dow Corning is equally as good if not a touch better than Sikaflex and is often a bit cheaper

Seahouse:

the glass will be brittle from UV damage

Are you sure uv light damages and brittles glass? If so, isn’t glass possibly the wrong material of choice to be used to let light into a building?

Slackman I would agree it sounds contradictory but glass is a UV filter and along with the differential temperatures from internal to external over along period of time becomes very brittle and will crack if you rack the window. One other thing I would suggest Al is if you still have your sash cords operational put a nail through them into the casement befor you take the sash out or your sash weights will fall inside the casement . Noob error.

Ta again. I know the decent timber merchants in Leith, glass does flex a bit in the sashes that are weak. The 2 worst are well painted in upper ones so I may just try bodging in the lower spar in situ. I’d have thought glass removal would result in breakage? Will see what I can do tomorrow, last dry day for a bit, CBA dealing with rain without windows, despite secondary glazing.

Well I found that a combo of treated rotted wood and filler stiffens things up quite nicely (Vicar) so I did that to the part that fell off and stuck it back up with filler and dowels, fingers crossed!

More to come…

IMAG0008 by alan cole, on Flickr

What’s knackered this sash rail(well the Upper Counter Check, to be precise)is condensation running down the glass into the wood and rainwater running in behind old, brittle putty.The weathered wood has then been painted trapping the moisture inside.
In my experience repairs like this won’t last; if the rot hasn’t spread to the Stiles (vertical members) then a new rail can be let in (about £100) or a new sash made and fitted (about £275 inc glass).
If people used microporous paints like Butinox rather than the death-knell for weathered wood that is gloss/acrylic paint then windows would last much better.
I’ll reserve judgement on the Slimlite double-glazed units untill they’ve been around a while; people don’t always use Butyl Putty to bed them in and if water gets past the putty the unit will fail

Good work Al. Always satisfying sorting something out like this and being able to get a few more years out of it 🙂

Ta waswas…no carbon fibre spoons were hurt in the process.

chickenman…you are Edinburgh also? It’s rain that’s wrecked it, interesting re porous paint…and porous putty?

I don’t expect the repair to last – if I’m still here in a few years I’ll put a new rail in myself.

Hmm perhaps doing it at night after some wine isn’t the best idea? Patched it up OK tho.

IMAG0009.jpg by alan cole, on Flickr

Anyway now to part-replace the rail in the other sash…My money is on man at timber supplier saying “we only sell it in 2.4m lengths” 😡

IMAG0010.jpg by alan cole, on Flickr

Actually he said “we only sell it in 4.8m lengths 🙄

Happily warehaouse man gave me a “sample” which has now been suit to size-ish (badly) and is drying-in

IMAG0015.jpg by alan cole, on Flickr

I’ll reserve judgement on the Slimlite double-glazed units untill they’ve been around a while; people don’t always use Butyl Putty to bed them in and if water gets past the putty the unit will fail

One of the 8 I have has failed