Help needed with u values, and does this look a fair quote?

[lardconcepts]

Living off the mains gas grid, heating with LPG is expensive. Twice the price, if I've read this table correctly: http://www.nottenergy.com/energy-costs-comparison3

We've done all we can with insulation, but the current double glazing on the windows is old and incredibly thin (4mm or something).Last winter, the snow remained on the roof all the way through until the melt, but the velux windows were melted off in about an hour!

We had a quote from a local manufacturer, and actually, it's not as bad as I thought it would be.
This is for replacing the glass into the current, sound, traditionally shaped wood frames, including curves at the tops (so glass needs to be shaped)
I've turned his paper "pick and mix" quote and u-values into a spreadsheet for my own info - does all this look right?

https://spreadsheets.google.com/ccc...NjVGTXhMOXI0b3JWZXc&authkey=CIzSz7wL&hl=en_GB

In particular, note the decreases in u-values regarding the filler gas vs the increase in price. Is it actually worth going for Krypton?

We're hoping to get a fair bit of passive solar gain through the south facing patio doors and windows.

The company come well recommended locally and by neighbours, and to be honest, the bloke doing the quote was so pleasant and un-pushy, if you think this looks fair I don't think I'll even bother with a second quote.
The last time I got a glazing quote at my old house, it was a thoroughly unpleasant and pushy experience and came to a stupidly high price so I didn't bother.

Anyway, whaddya reckon? Do my sums make sense? Googling around here and elsewhere seems to show that having a gas fill is definitely noticeably worth it, but would you bother with the krypton?

Thank you.

 

[Mw Roofline]

Living off the mains gas grid, heating with LPG is expensive. Twice the price, if I've read this table correctly: http://www.nottenergy.com/energy-costs-comparison3

We've done all we can with insulation, but the current double glazing on the windows is old and incredibly thin (4mm or something).Last winter, the snow remained on the roof all the way through until the melt, but the velux windows were melted off in about an hour!

We had a quote from a local manufacturer, and actually, it's not as bad as I thought it would be.
This is for replacing the glass into the current, sound, traditionally shaped wood frames, including curves at the tops (so glass needs to be shaped)
I've turned his paper "pick and mix" quote and u-values into a spreadsheet for my own info - does all this look right?

https://spreadsheets.google.com/ccc...NjVGTXhMOXI0b3JWZXc&authkey=CIzSz7wL&hl=en_GB

In particular, note the decreases in u-values regarding the filler gas vs the increase in price. Is it actually worth going for Krypton?

We're hoping to get a fair bit of passive solar gain through the south facing patio doors and windows.

The company come well recommended locally and by neighbours, and to be honest, the bloke doing the quote was so pleasant and un-pushy, if you think this looks fair I don't think I'll even bother with a second quote.
The last time I got a glazing quote at my old house, it was a thoroughly unpleasant and pushy experience and came to a stupidly high price so I didn't bother.

Anyway, whaddya reckon? Do my sums make sense? Googling around here and elsewhere seems to show that having a gas fill is definitely noticeably worth it, but would you bother with the krypton?

Thank you.

Yes it's worth the extra for Krypton. What is the overall thickness of the sealed unit, 24mm? Can you fit a 28mm in there? If so I know a system that will give you a U-value of 1.0

 

[lardconcepts]

Thanks for the reply, Roofline!

I think we'd be very lucky to get any more thickness of glazing in the current frames. 28mm would be a miracle!

Here's how thin the patio door currently is: http://goo.gl/7nTK6
And here's how foggy the fogged up old glazing with 5mm gaps which makes up most of the rest of the windows are. http://goo.gl/PKh9R

Since making the first post, I found a couple of things out, the first of which has made me have a major rethink about the whole thing. The guarantee on the sealed units, ie, the double glazing that goes inside my frames, is 1 year. Which is about 9 years less than I was expecting! I'll probably get the worst two units done.

Also, I asked about Kyrpton vs Argon, and also Planitherm, which was mentioned but not quoted for. When I googled it, it seems that Planitherm is actually better than Pikington K.

The reply from the company is:
"The thing to remember is Krypton is more efficient the narrower the airspace where as argon works the opposite way. We can do planitherm which is the same price".

So should I forget about the Pilkington and go for the Planitherm?

One thing I maybe should mention is that it gets cold where we are in Wales. Very, very cold. Like, -16c last winter. And for 3 days running, the accurate, well-placed outdoor thermometer never registered a daytime high of less than -6c for 3 days running.

 

[Mw Roofline]

So should I forget about the Pilkington and go for the Planitherm?

Most definately. Planitherm is brilliant.

Good luck