In article , mark b mark@norwich
a1.freeserve.co.uk writes

I bought some tubes of low modulus silicon sealant to bed double glazing
units' into a timber frame.

When I read the tube it said:
Do not use in contact with the edge sealant of double glazed units.
If it was acetoxy cure (vinegar smell) I could understand that, but I would
have thought that neutral cure would be ok. There is specialist glazing
compound that comes in the same kind of tube that would def be ok,
available from sheds or srewfix - code 12954 clear or 18636 white.

As I live in a city & have ground floor windows I will be putting some new
units in with security glazing tape (double sided strong foam tape), back
filled with neutral cure low modulus silicone & finished with beading that
came with the frames.
--
fred