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How to repair wood rot and re-seal window sill?

finn2018
Community Newcomer

How to repair wood rot and re-seal window sill?

Hi Everyone, 

 

How can I go about repairing this window sill of wood rot? 

Screenshot 2024-09-23 at 11.16.10 AM.png

 

I've read through this article which was very helpful and also purchased Turbo Timer Rot Repair Kit, however, as it's inside, I would hope to use builders bog that is stainable so it can match the rest of the frame (picture 2). 
We've also bought Selley's Roof and Gutter Sealant

 

Screenshot 2024-09-23 at 11.17.04 AM.png

 

It seems like I would also need to reseal the glass at the bottom to prevent more water seeping through. How do we prep the area and what is the best method? 

 

The windows seem to have this between the glass pane and sill (from another window): 

 

Screenshot 2024-09-23 at 11.59.45 AM.pngScreenshot 2024-09-23 at 12.00.02 PM.png

(I've also checked the wood of this sill and it's hard, and seems to just be surface level water stains that are in need of re-staining) 

 

Any tips would be greatly appreciated! 

 

 

EricL
Bunnings Team Member
Bunnings Team Member

Re: How to repair wood rot and re-seal window sill?

Hello @finn2018 

 

Welcome to the Bunnings Workshop community. It's sensational to have you join us, and thanks for sharing your question about re-sealing your window sill.

 

Just a friendly reminder that working around glass is dangerous and an accidental hit or a sanding tool pushed too hard could shatter the glass and cause injury. Please take extreme care when working around glass. Please remember to wear personal protection such as thick gloves, goggles and a mask when working on your project.

 

The general steps would be to sand the timber surface to remove the old layer that has dried up and faded. Next is to test which part of the timber has rotted, tap the surface with a screwdriver to see which parts are brittle and have given way. The rotted parts need to be removed, but if too much of the timber has been compromised the frame will need to be replaced. At the moment, I don't recommend removing the thin filler that is currently next to the glass as it is keeping it in place.

 

On the condition that the frame is still in good condition and can be repaired the next step would be to use the builders bog to fill the damage. I suggest painting the bog in a dark brown colour close to the finish you're after before staining the timber. In regards to the thin timber filler, I propose engaging the services of an experienced handy person or builder who might be able to recognize what that material is. 

 

I recommend using the Sika 300ml Sikaseal 300 Glass And Weather Seal Silicone Sealant - Transparent outside to seal the glass.

     

Let me call on our experienced members @Dave-1 and @Nailbag for their recommendations.

 

If you need further assistance, please let me know.

 

Eric

 

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