In article , Tim S
writes

Is it possible to get replacement units and fit them myself. If so how
should I specify dimensions and where do I order them from.

Yep, go for it, wooden beads are relatively easy to pop out. Using self
adhesive glazing tape fitted to the inside of the frame when fitting the
new glass will stop a burglar removing the pane in the same way.

I did phone one supplier but he said they need to be measured and fitted
by a professional which seem a bit strange.

Sounds like protectionism to me.

If you mean the double glazing panels (units) then any high street glazier
should be able to make or have them made for you. Varies between 70-100+
quid / m2 from plain old annealed glass to annealed K glass to toughened K
glass to argon filling.

That is probably the most expensive way to by them, a glazier rarely
wastes time making up DG units, they buy them ready made from a
wholesale glass merchant and will mark them up before selling to you.
Some wholesale merchants are happy to deal with sole trader handymen and
a competent DIYer should easily be able to pass for one of them, buy
from the wholesaler. Look under glass merchant in the Yellow Pages.

It would be best to pop the beading off and exactly measure your existing
units then quote that size to the glazier.

I wouldn't dismantle before the replacements are available. The glass
bearing part of the frame is visible and easily measurable, measure the
glass bearing opening and subtract 5mm to get the glass size for
ordering. Existing unit thickness can found by measuring the frame
thickness and subtracting the inset measurements to the panes on the
inside and outside.
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