Best way to fix a rotten cill

Nagme

DH has just managed to rake out about 50% of soft rotten wood from our wooden patio door cill. The previous owners had a go at it with silicone years ago by the looks of it, but at least we now know why there are so many woodlouse walking around in the lounge.

Before we spend any money on DIY products, has anyone got any recommendations on the best way to prevent it from getting worse and falling out, filling the gaping hole and hopefully helping our patio doors last a few more years?

TIA

Nagme

Nagme

Jonesya

Given how much has rotted away I think I'd be looking to cut it out and replace all or a section of it with new wood.

Also with it having rotted all along the edge between the timber and the door frame, I'd be wondering if it's not draining properly and water is running/pooling around that area and the cill needs more of a taper/angle to get the water away.

ian103

For a bodge job you could use something like isopon, used it in the past successfully as a temporary (medium term repair) whilst saving the cash for new windows - it will last a few years but it reality the proper fix is a new cill or it may be sensible to fit a new door.

Nagme

Jonesya wrote: »

Given how much has rotted away I think I'd be looking to cut it out and replace all or a section of it with new wood.

Also with it having rotted all along the edge between the timber and the door frame, I'd be wondering if it's not draining properly and water is running/pooling around that area and the cill needs more of a taper/angle to get the water away.

We think the roof gutter was leaking onto it. We replaced the gutters last year.

The cill itself is almost 2m long and goes under the (double) patio door to the lounge, and is part of the entire frame.

NeverInDebt

Yeah could use some good quality hard filler like said above but in long run probably better to replace whole cill

cyclonebri1

Truth is it's gone, rotted, deceased infact.

You need a new frame or better, a new door set.

Please don't let anyone convince you it is recoverable

Ectophile

I've used Ronseal Wood Filler to fill a much bigger hole than that in a window sill. You can also get a liquid which helps to stabilise any surrounding rotten wood - paint that on first, and let it dry.

The hole in my sill was so big that I used offcuts of wood (which was meant to be kindling) mixed in with the filler to bulk it out.

I'm under no illusions that my bodge repair is anything permanent, but it will do until I have the windows replaced.

I_have_spoken

A temporary fix would be a good soaking with preservative and wood hardener.

Then fill but in several stages, building up the material in layers and letting dry. Try to blob in a huge amount of filler in one go won't work.

Nagme

Thanks everyone for your posts.

Yes in the long term we aim to replace with new - it's an old unit and not good at keeping the cold out during the winter months, however for the next two years we really want to clear our debt, so a temporary fix will be ideal.

We have spent £39 and bought some wood hardener, wood filler and external paint. When DH opened the tin of hardener, it was only half full! Very misleading.

DH has made small drill holes into the wood (exactly what it said on the tin) and coated thoroughly with the hardener, then the larger hole has had some pieces of wood put in to fill out. We're waiting for a first layer of filler to set.

So much wood filler would be needed though, DH is now saying it would be worth filling with expanding foam then with filler, and finally paint.