Reply to thread

Something like this for stormproof hinges;

http://www.isaaclord.co.uk/prodData.asp?prodid=1288&SubCat=5

There are two schools of thought for fitting dg units with silicon glazing compound. One is to completely bed the unit in silicon leaving no gaps, the other is to provide drainage to the edge of the dg unit. This is achieved by only sealing the glass where it presses up against the inside face of the rebate. The glass is offered up and a gap is left all round the unit by packing the unit with spacers. I find it's best to make the rebate slightly deeper to accommodate it and hide the metal edge. I cut two or three slots in the bottom rebate to provide drainage; the  bottom glazing bead projects out from the frame and has a drip bead incorporated when this is fitted you need to make sure the drainage slots aren't blocked with silicon. Then the rest of the glazing beads can be fitted making sure the gap round the dg unit isn't filled with silicon.

I don't know if this make sense :roll:  but this is the recommended method of fixing as far as I am aware, but to be honest I'm not sure it makes much difference. Even in plastic windows, with thoroughly drained edges, the dg units are still prone to fail. It strikes me that many units are faulty at manufacture but it takes a long time, years, for the tiny hole to fog the glass because the desiccant in the beading absorbs the moisture for a time.

Keith