Water damaged window board

[wallaceoc]

Hi,

I have a 5 pane bay window in a bedroom and the MDF window board under one of the panes is showing signs of water damage below the centre (roughly) of the pane. The edges (up against the wall on one side and the next pane on the other) seem ok so far.

Is there any way to figure out if this is water from condensation on the window running down on to the window board or coming from the outside?
The house was re-rendered about 5 years ago and the window board is the same age.

I have attached a few photos of the window board.

Thanks

 

[jacko555]

My thoughts: if it was condensation, the paint would be discoloured / obvious the damage is from surface water. That looks like internal moisture. However, not an expert.

Maybe ask to move this to the windows section?

 

[opps]

As a decorator, that looks like water damaged MDF was was painted over rather than MDF that has become wet since it was painted. You would expect blisters in the paint if it was an ongoing problem.

 

[wallaceoc]

My thoughts: if it was condensation, the paint would be discoloured / obvious the damage is from surface water. That looks like internal moisture. However, not an expert.

Maybe ask to move this to the windows section?

I’ll try to get it moved . I did think about posting there originally but all topics I checked seemed more window related and not general.

 

[wallaceoc]

As a decorator, that looks like damaged MDF was was painted over rather than MDF that has become wet since it was painted. You would expect blisters in the paint if it was an ongoing problem.

Thanks. I’m thinking about chopping out a section around the damage to see if the damage goes all the way through to the bottom etc. and refilling with 2-part filler.

In your opion as a decorator is this more of a long term fix for a decorator, window fitter or general builder?

Thanks

 

[opps]

Thanks. I’m thinking about chopping out a section around the damage to see if the damage goes all the way through to the bottom etc. and refilling with 2-part filler.

In your opion as a decorator is this more of a long term fix for a decorator, window fitter or general builder?

Thanks

The damage is unlikely to be significant, if it were the affected areas would be spongy, as in you would be able to push them down.

If faced with that I would cut away the silicone and sand the raised section flat, difficult to do without a decent random orbital sander. You will however find that once to sand the old paint away you will hit the fibrous part of the water damaged MDF. The current paint has "locked" the fibres, sand through that an you will find the fibrous fibres pop up.

There are a number of ways to seal the "punky" MDF (read: fibrous). I use either epoxy resin wood hardener or Owatrol oil but there are many other options.

I would rather sand the raised section flat instead of using two pack filler over it but only because I don't want the risk of the 2 pack delaminating in time, but two pack is the easier option.