I have a large custom made 2nd floor window which forms virtually the
entire end wall of what was an attic room. All architect designed, and it
does what I wanted perfectly. Lots of lovely light.

The load bearing frame is made from 4x2" timbers, dividing the window into
15 off 22inch square double glazed units (3 rows of 5)

The glazing units are fixed on both sides by what I think it called Staff
Bead, mitred to fit and pinned in place.

Most of those beads on the outside have rotted. Despite having been
painted regularly. Which isn't an easy job as there is a conservatory
underneath which means scaffolding.

The structural frame appears to still be in very good condition. So I'm
assuming water finds its way behind the bead and causes it to rot.

Any suggestions for a better material/shape for those glazing beads? PVC?
Hardwood? Material cost isn't much of an issue given the overall costs of
getting at them and painting etc. A bit of Googling shows companies who
sell a wood/PVC mixture supplied primed. But I've no experience of this,
hence the questions.

It faces almost due south and is as exposed as it could be. So
recommendations for the best paint to use (white) would be good too.

--
*Virtual reality is its own reward *

Dave Plowman London SW
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