Double Glazing Units

[zcacogp]

Chaps,

I'm making some sash windows, and want to install some double-glazing units in them. This will replace the existing sash windows which are single-glazed and rotten.

I have the sashes made up to undercoat, and have taken them along to my local glass framing place whom I have used before. For the 10 units I need making I have been quoted £322+vat. (This works out at just shy of £390 all in. For reference, I made another single sash which only had three pieces of glass in it about 6 months ago, and single-glazing panes for this came to £12 - £4 each.) I know this place doesn't make up the units - they are passing the work out elsewhere.

This strikes me as being very expensive ... are there any cheaper ways of getting double glazing units made up? Whom should I talk to, where should I go? I am in London, but for these prices I am happy to travel a bit to find the right solution.


Oli.

[Simpo Two]

I used this lot: www.colchesterwindowwarehouse.com

They make the frames on site - although the sealed unit part goes out, they weren't expensive. Might be useful ringing up for a quote.

[markbigears]

These guys make all there own windows / doors / frames on site and are very reasonable.
Father has just used them and I had a quote for an alu door which was half the price of another firm.
http://www.swandoors.com/

[zcacogp]

Simpo2, MarkBigEars,

Thanks for those contacts. I have some quotes from them (and others).

The next problem is that there is a huge variety in what I can choose from, and I am feeling a bit of a fool on the telephone when asking for prices. The windows being made are sashes, and replacing existing sashes (the existing ones are rotten, and I would like to put some better insulation in at the same time.) Therefore, as far as the legislation goes, I can do anything as long as it is as good or better than the existing glass (which at 4mm victorian panes isn't hard.)

The question is whether any of the extras are worth paying for? They seem to be as follows;

- 'Warm Edge'
- Argon Filled
- 'Soft Low E' Coating on the inside of the outer pane of glass (apparently not the same as a hard coating)

How much difference are these bits going to make to the warmth (or otherwise) of my house? As a price-guide, the difference between plain float glass and all-the-bells-and-whistles is going to be about £90-100 for the whole job. Is it £100 well spent, or money wasted?


Oli.

[Blakeatron]

We only used Argon filled, hard coated glass - silver or dark brown bandings depending on wood colour.

Bandings are the colour of the metal bit you see between the 2 glass panes.

I would not go less than 4/8/4 - A decent compromise between insulation values, noise reduction and bulkiness.

[zcacogp]

Blaketron,

Thanks. is this for new properties or replacement windows in existing walls?

4/8/4 is the thickness of the glass, the gap and then the glass - non? I could go this thick, but it would be difficult; 4/6/4 (total 14mm) would be easier. Will I notice much difference from losing those 2mm?

Thanks for your advice.


Oli.

[Blakeatron]

For new builds we would go a lot thicker than a 16mm unit - we would even push for triple glazing...

If you are desperate then yep squeeze it down a bit more to a 14mm unit, a lot of the insulation value can be increased with your window dressing - thick heavy curtains are better than blinds etc.

Anywho any double will be better than a single pane!

[MJG280]

I have had to replace some sah window glass and double glazed isn't an optio. Glazier suggested laminated not only on the low areas and it is quieter and warmer than ordinary single glazed. Also cheaper.

Our council years ago put UPVC windows into council houses. The glass was very thick and single glazed and seemed to have a green tinge to it. Seemed to work as well as double and I believe bricks and half full cans of Stella bounced off

[herewego]

The optimum gap between panes for insulation is about 15 or 16mm. If you have to use less then argon filling is a good alternative. Argon is either more viscous or more thixotropic, I can't remember which, than air which reduces the convection movement and therefore the heat transfer between the panes. I believe even a 6mm gap works if there is argon in there, but doesn't achieve much if just using air.

[zcacogp]

To finish this one off, I went with Markbigears's suggestion; Swan Doors and Windows. Dealt with a very affable chap there called John who produced a quote that was a good chunk cheaper than their nearest competitor (and half what my local glazier wanted.) To put the icing on the cake, they included the things that would have put the price up further with the other people - those things being Argon filling and Soft Low-e Coating (whatever that is), and had them done within a week. I collected them yesterday (drove home very carefully with a big pile of very expensive glass in the back of the 944!) and they are all perfectly to size. Swan don't make them, they have them made by a company in Essex, but their prices were still the lowest.

So, thanks to John at Swan Doors and Windows. Their website is www.swandoors.com.

Thanks Markbigears for the suggestion.


Oli.