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How to replace a rotten window frame?

Our guest bedroom as a large window that goes close to room to ground. One corner of the window appears to be rotten (or at least damaged.)

I don't think can be recovered by hardener etc. I think that this job is probably beyond us - but what kind of trade would you call for a job like this and is it possible to DIY ?

Also - I think the issue is there is limited drainage on outside path that meets directly to window. Would some kind of drainage or lowering the path stop this from happening in future (or should be considering changing size of window all together)

I have added the picture from outside and inside. The paint removed, I've just peeled away my self.

Any help / tips would be great !

Thanks !

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JacobZ

Hi @FMaree,

Thank you for reaching out for assistance with your rotten window frame.

Unfortunately, I don't think this would be a D.I.Y. job, as there's no real way to know the extent of the damage without removing the timber. The piece where you've removed the paint is going to be mounted to the framing behind it, and if it has become rotten, there's a good chance the framing behind it is rotten too.

Does the bottom rail also feel soft or rotten further along the window? Or is it just that corner there?

By the looks of it, you are getting a leak in that bottom corner, which means there is a gap in the outside of the window that would need to be sealed. This may be a simple case of sealing up a gap with some silicone, or it could mean removal and reinstallation of the window.

Depending on the severity of the water damage, you could be looking at two separate tradespeople, a glazier and a carpenter. If I were to look for a single tradesperson to start with, I would use a service such as HiPages or a quick Google search to find a carpenter who has experience with window repairs. I quickly Googled "window repair carpenter" and found a few options near me. They should be able to come out, assess the extent of the damage and recommend a path forward and advise whether you also need the assistance of a glazier.

Looking at the level of the bottom window relative to the ground outside, I'd say this is a major factor in why this damage has occurred. At present, any sitting water is pretty much at the level of the window. As part of the repair, I would suggest that the ground needs to be lowered by at least 100mm below its current height, and a surface-level drainage channel be installed to carry away any surface-level water. Keeping the water away from the bottom of that window is going to be essential to prevent this from recurring.

Allow me to tag @Nailbag who is an experienced handyman for his thoughts.

Jacob

Nailbag

Hi @FMaree

Before attacking the repairs, you need to rectify the cause. there is one obvious one that @JacobZ mentioned being the high of the gravel outside to the window sill, and potentially the sides of the window.

The stones on the outside need to drop minimum 50mm. Then I would clean the rubber sill as well as the side frames edges where it meets the weatherboards. Then apply a clear exterior silicone to the entire framed area.

Give it 24hrs to dry then do a test with using the garden hose on the window to checks thats resolved the water ingress.

All going well you will need to dig/cut out all the soft wet wood from the internal frame and allow it to dry for a few days. Now apply Earls wood hardener and prime coat paint the area.

Fill the damage with builders bog and use a sharp chisel to scrap away the excess s prior to it fully harden to save extra sanding. Then sand prime and paint.

Nailbag

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