I could do with some advice from those with experience and knowledge in glass roofs! We have two quotes for the construction of a 6mx3m south facing conservatory.

Quote 1 involves an ultraframe roof with 'Thermaglass' manufactured by Custom Glass of Liverpool. The units apparently have inner pane is made by St Gobain of France and the outer pane is a bronze tint anti sun by Pilkington. Cavity is argon filled and has a U value quoted as 1.1

Quote 2 involves a K2 roof system but we are provided with 2 glazing options, either Celcius or K Seal both with a U value of 1.4 and I dont think either involve argon. Sales lady says argon filling is a problem as it can leak out and require refilling (how would you know?)

Can anyone let me know the pros and cons of these options and whther one is recommended above the other

Argon filling helps with the U value of units by so much that people dont realise how important it is. U value changes on DGU when you tilt them into a roof so the Argon becomes even more important on roof units.

As an alternative to Celsius, try Reflex as it has the Edgetech super spacer technology instead of the traditional metal spacer bar. This is the primary seal on the DGU and therefore the Argon is far more likely to stay in situ. Also they offer a 20 year warranty on their units against seal failure, which means you have no chance of condensation inside the cavity of the unit. All manufacturers offer warranties on their seal but they can never be really sure of how good it is on any single unit with the traditional aluminium spacer bar but with the super spacer it provides a permanent seal. You then have the hot melt (black goo) as the secondary seal (which is what normal aluminium DGU use as the primary seal). The warranty may cover this but the hassle factor of getting a failed unit replaced is not really what you want to have to experience.

You should be thinking of a solar control glass for the roof, and not just any old low E glass otherwise you will end up with a Sauna. Ask your installer for promotional literature on the above brands or search on the internet yourself for more info.

Tanner

I would recommend reflex glass as a proper solar control performance glass for conservatory roofing.

Whats interesting with reflex is that they offer a clear solar control option to help reduce the heat build up from sunny south facing jobs. So blue tint in the roof and clear in the side frames gives one hell of a solar control installation.
We used it recently on a job and it felt instantly cooler when you walked under the glass.

www.reflexglass.co.uk