How to repair rotting timber window sill?

[lilh]

Hi, 

I have an old house with wooden exterior window frames/window sills. 
A few of these are in pretty bad shape, how can I go about restoring or repairing these?

In the photo attached you can see the paint has started to peel away. The wood is brittle in areas and soft in others. 

I would appreciate any help! 

Thanks

 

[DIYGnome]

Hello @lilh 

There are a few different schools of thought (and approaches) so I will simply detail the process I use and other members will hopefully chip in with their suggestions 😉

@Dave-1 

Essentially it depends on the degree of wood rot, if severe I strip down the frame (or cut out bad sections) and replace the wood as required but if only partial damage has occurred I prefer to dig out the nasty soft rot until I locate some "good wood" applying wood stabilizer helps prevent moisture seepage and shores up the remaining timber, for this I use PVA wood glue but specific products are available. 

Builders bog or automotive body filler is my filler of choice, sand and paint 👍

[JacobZ]

Hi @lilh,

Thank you for your question and welcome to the Bunnings Workshop community, it is great to have you with us.

It's great to see you've already received some advice from @DIYGnome which I completely agree with.

I'd advise you pick up a Turbo 500ml Timber Rot Repair Kit, which includes a wood hardener, builders bog, putty knife and sanding block.

Like DIYGnome has said, dig out the soft stuff until you hit decent timber, clean the area up sufficiently then apply the wood hardener following manufacturer's instructions. Once dry, apply your builders bog with the putty knife, once again following the manufacturers instructions, then sand back to a smooth surface. Once done, paint over the top.

Let me know how you go and if you need any further assistance.

Jacob

[Dave-1]

Afternoon @lilh 

Depending on how bad the timber has rotted (If its rotted my first thought is to replace the timber) you can repair it as @DIYGnome has mentioned. I have seen some very nice wood restorers and if the timber isnt to bad (push a flat blade small screwdriver into various sections of the frame and see how bas it is) then the easist way would be the Builders Bog.

If the timber is spongy along the length of it or even spongy all the way through then I would replace the bottom sill. I cant tell from the photo if the window is sitting on it or if its just a fron face type piece. If its a front faceing piece then you could remove and replace. You could use a Ozito 300W Multi Function Tool MFR-2200 to cut it out easier.

Dave