PVC window in wooden frame (threads merged)

25 Feb 2014
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United Kingdom

I have a pvc window in the bathroom which is framed by wood. Unfortunately the wood wasn't tiled over and as such has started to rot due to water from the shower.

The wood has pvc trim on top of it so I plan to remove the trim and cut out the rotten wood, replace the wood and attach the trim back. Just wondering wether the wood needs to be treated? As there won't be any bare wood once I put the trim back on and tile over the last visible side?
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No problems. Please see attached photo of the window.



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I can't see any value in using treated timber if the rest of the frame is not treated. And TBH, even if you buy treated, you will cut it and need to treat it again on all the cut sides!

Just seal it properly as the problem seems to be caused by poor sealing and internal humidity and not by anything else
Comes from always having treated timber and end seal on hand in my job. I'd have suggested teak or iroko, which
will last decades untreated, but have you seen the price?
How would I seal it properly?

Also, would there be any need to replace the wood? I was just thinking if I cut all the wood back to the window then there would be a flatter surface to tile. Or would there be a reason to replace the wood I cut out?
You would seal it with either gloss paint and silicone or a uPVC cover strip and silicone
Is there a reason I should replace the wood? Is there any reason I shouldn't just cut back the wood and seal the bare wood level with the window?

I suppose if the rot continues beneath the window, I would need to to get the window removed and replace all the wood?
What we sometimes do with rotted sash windows is to chisel out the punky timber, clean out any loose or soft stuff remaining with a steel wire brush (you need to get rid of any soft/rotted timber) then treat the remaining timber with wood hardener which treacts with moisture in the wood and air to set (ruins the brush though and turns skin black, so cheap brush, gloves and old clothes required). Gaps are then filled with 2-pack filler (even catr body filler will do). Providing the frame is still about 60 to 70% there it works, although it is never as neat as doing a replacement and it isn't permanent (however it will last a few years),. The one I've used for a long time is Bonda Wood Hardener
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I have an old flat which has a wooden window frame around a pvc window. I need to replace the bottom section of the frame as water has gotten underneath the pvc trim and rotted the wood. See photo. Looks like I will need to replace the whole of the wooden frame on the bottom so I was wondering, rather than replacing with wood, is there any pvc products I could use to replace it instead? Just looking for ways to ensure it dosent rot again. Any advice appreciated.


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I am not a builder or carpenter but i would just get a new complete window for all the faffing about that would involve.
The window itself is fine, it's the wooden frame round it that needs replacing.
Thanks for the advise JobandKnock!

I have pulled off the pvc trim and it looks like I will need to fully replace the bottom length of wood (see photo)

Is there anything other than wood I can replace it with? Like a pvc block or somthing? Just trying to work out a way of preventing this in the future.


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