I'm based South East London.
At the back of my house, there's a back door flanked by two old wood panels all with single glazed panes of glass. The panels are all identical door sized with half height single glazed windows and the centre door is an identical panel hung as a door. I want to swap the single glazing for double glazed units (just the double glazed units without any form of surround). Doing this, I can turn the door sized side panels into large glazed windows (6ft x 2.5/3ft approx) (just a case of removing old fittings from wooden frame and replacing with large glazed units). It's to be an economical improvement which will warm and brighten the very cold back room of the house.
So, I'm looking for a competitively priced supplier of double glazed panels. It could be local-ish in South London or an online supplier. I'd like to be able to choose the right glass, gap sized, thermal values etc so I can ensure security, safety and insulation. My local double glazing shop didn't provide much variation in spec and materials.
Could anyone suggest a good and reasonably price supplier - I'd be happy to order online if there's a site with an online calculator etc if that's an option - given I'm based in South London.
Thanks for any help.