Been on the vino James?

No paint can work on wetted/moulded substrate. If wet, paint will fail. If drying from wet, paint will fail. If mould growing on the paint or under the paint, it will fail. Mould growing under glass indicates ineffective putty seal. I presume you are using putty because the trade advises it. Trade is for profit and frequent maintenance produces profit. Therefore you must be doubly careful with that. The most effective general purpose sealant you can get is the hybrid polymer. It will work on most things except some plastics. The rot is caused by water getting to the wood. The water is entering at the corner between the rotted piece and the surface it is attached to. The attempt to seal that corner with paint has failed. A bead of sealant will work. All corners at risk of paint cracking from thermal expansion and contraction should be sealed.And it has got worse, bubbling up. So much for Weathwrseal paint!


I'm not suggesting taking the putty out; I am suggesting temporarily dressing lead work over it to provide a seal until such time as a proper structural assessment of the situation can be made.You try taking that failed putty (bad batch) out and the glass. It isn't easy. I'll ignore the supercilious sarcasm.

I was thinking this too, a structural engineer indeed lol.A structural engineer, not sure if this is sarcasm or not? Its a potting shed not the Burj Khalifa!
What “bubbling” ?Well I sanded the surface down and painted again and overnight it has already started bubbling with NO rain. I just can't believe this!
DIY windows seldom work

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