Windows - double glaze or not

[spoonylucy]

Hi All

Starting to get quotes in for some of the big jobs that need doing to the house. I have so far had two quotes for the windows. I have 12 windows in the property which are Yorkshire Sash (horizontal type).

The first quote was they all need replacing which I thought was very excessive as some are not too bad. The second quote I am very impressed with as it has included details of each induvidual window and what needs doing to them.

The second company can save them all and have price one for just refurbishment and one for refurbishment with double glazing. The price is £8000 more to have them double glazed and would take a very large part of our renovation budget.

My question is that is it worth paying all that extra to double glaze them? The house does sit off from a main road but you really can not hear the road and the walls are 18 inches thick.

Your comments are much appreciated.

Thanks

Sharon

 

[biffvernon]

Sharon, I'm really not touting for trade, (those of you who are waiting for my completion of orders will be glad to know I'm not promising anything for new customers until at least next spring) but £8000 more for double glazing 12 Yorkshire sashes sounds expensive. Depending on the size, I might make 12 Yorkshire sashes, double glazed for around £8000.

On conservation grounds it would be better to repair than replace your windows. If they really are beyond repair, then it makes a good deal of sense to change to double glazing (as well as being necessary for Building Regs compliance). Your heating bills will be reduced and/or you will be warmer. I charge the same price for a new window whether it is single or double glazed.

 

[JoceAndChris]

Good post from Biff there. If the windows can be repaired that would be better and then to consider secondary glazing.

We didn't /don't have a huge budget for sash window repair. We doing the place up room by room, including that room's window repair within the other tasks the room needs. Dad has just spent 2 or 3 solid days repairing the dining room window- removing rot, carving (!) a section of mahogany to go in the sill, moulding the beading with a router to match a rotted out bit, splicing in little bits of wood here and there with brass screws and patching with filler. I watched him to see if I could do it next time, and my conclusion is I couldn't. I'm very lucky to have him, I know. He is getting on though, and I think a younger competent joiner would have cracked through what needed doing in far less time, presenting with a bill that certainly wouldn't be £1000s.

Curtains, very thick ones, make a tremendous diference too.

 

[spoonylucy]

Hi
Thanks for that, i am going to go with repairing all of them as this is the far cheaper option and keeps the lovely windows I have.

You can see from the link all the windows I have and some are bad, only a couple of them will even open at the moment.

http://www.vebra.com/lawsons/property/22261850

Thanks

Sharon

 

[Penners]

Sharon - I quite agree with the comments above. £8000 just to double-glaze is a hell of a lot of money. According to the Energy Saving Trust, double-glazing all of your windows saves, on average, about £135 a year in fuel bills. So, on that basis, you could pay for your double-glazing in a mere 59 years. :shock:

If it were my house, here's the approach I would take:

1. I would have the existing windows repaired as they are.

2. I would look at every possible way of insulating the house, other than double-glazing. For example, is the loft insulated to modern standards? The cost of this will only be a tiny fraction of what you'd have paid for double-glazing.

3. I would experience the house for a few months in winter, to see just how necessary double-glazing actually is. If I felt that I really needed it, I would then consider (depending on my budget) either professionally made secondary glazing or a DIY system such as Easyfix. (http://www.tubeway.co.uk/efxglazsyst.htm). It looks a bit jury-rigged on paper, but in practice it's actually quite unobtrusive.

 

[88v8]

Nice house.

If you have olde wonky crown glass, I wouldn't even think of removing it.
If the windows are already glazed with float, then double-glazing (black separators) will make little visual impact.

To me, originality and appearance come first and last. Originality can only be destroyed once.... The windows are pretty small so the heat loss will be little. I read in New Scientist a while ago, a research project in Scotland where whey found that well-fitting curtains - as already said - or shutters keep in as much heat as double glazing, and if you have no noise worries then as you say, that's not a factor.

I'd go for the repair option, but keeping any crown glass.
The main thing that makes sashes jam - horizontal or vertical - is painting them shut, and failing to treat the bottoms of Yorkshire lights with teak oil or the like to keep them from damp.

Oh, and the 'economics'... £8,000 (I realise that's not all double-glazing cost) but £8,000 can produce £400 a year in dividends, so you'd need so save that much just to stand still... which is why most energy-saving gadgets have a pay-back time of Never. :wink:

Ivor

 

[Moo]

Originality can only be destroyed once....

Cue a list of people who should have that tattooed on their foreheads ....



and a couple of additional (small) thoughts: shutters have the added advantage of increased security; make sure that your sashes are draught-proof.

 

[Penners]

£8,000 (I realise that's not all double-glazing cost)

Oh, but it is. I quote...

The price is £8000 more to have them double glazed

£8,000 can produce £400 a year in dividends

That sounds hugely over-optimistic to me.

 

[Moo]

Me too.
Please be kind and let us know where to go for that rate of return.

xx

 

[biffvernon]

£400 a year in dividends on £8,000 is 5%.

I'm getting a rate of return on investment of over 10% (tax free) on my solar pv system and 7.5% (before tax) on my investment in Ecotricity bonds.

To say that energy-saving gadgets have a pay-back time of Never is rather silly, though replacing sound windows with new double glazing will often have a very long pay-back time, as well as possibly removing historic fabric. To be fair, increased comfort has to be taken into account as well. Many people who improve the insulation of their houses end up wearing fewer clothes, somewhat off-setting the financial gains and carbon emissions savings.

 

[88v8]

£8,000 (I realise that's not all double-glazing cost)

Oh, but it is. I quote...

The price is £8000 more to have them double glazed

Oops, you're right she did say £8,000 more.

£8,000 can produce £400 a year in dividends

That sounds hugely over-optimistic to me.

5% dividend - GSK, Shell, MAN group, Scottish & Southern, Marks & Sparks etc etc.

My gas bill on our present solid-walled 1920s house is about £700 of which perhaps 40% is water heating. We heat the house to 60F which is plenty, old house, wear a wooly
So my heating bill is about £400. I doubt it would cost £400 to heat Sharon's house, and even if it did she'd have to save all of that just to stand still compared to the investment income she'd be losing, let alone 'pay back'.
£8,000 extra on double-glazing has a pay-back time of Never. Never never.
And that's disregarding the replacement of sealed units when they steam up. As they do.

It's a pity that so many energy-saving 'investments' barely break even when lost investment income is taken into account, but that's the arithmetic of it, alas.

Ivor

 

[CatherineB]

Hi Sharon
Without getting into the economic debate (I did recently spend a lot of money on secondary double glazing, which I hope to get back in terms of quality of sleep, never mind any small financial return from heating bills), I would second 88v8's vote that it would be a real shame to reglaze and lose any old glass. We have quite a lot, which is one of the things that swung us in favour of secondary, rather than reglazing.

 

[AMc]

If the windows are salvageable then do repair them you won't regret it.
Secondary glazing is very good - obviously you can see it from the inside but it's reversible and IME cheap enough to repay it's cost in savings in it's believable lifetime.

Even the Energy Saving Trust used to be honest about the "pay back" on replacing windows with double glazing being in the decades even though they used to recommend it :roll:

 

[biffvernon]

If you are replacing a window because the old one is no longer repairable and it is not a building of historic interest and there is no question of the loss of repairable fabric, then it makes economic sense and complies with Building Regs to replace with double glazing. If the new one is a well designed window so much the better.

I've been using the same manufacturer for my double glazed units for seven years, supplying hundreds of units, and, so far, nobody has come back to me saying their unit has steamed up. When I make a single glazed window I use mouth blown cylinder glass which is more expensive than a double glazed unit.

To say that 'double-glazing has a pay-back time of Never. Never never.' just isn't necessarily so. Life isn't that simple.

 

[JoceAndChris]

It certainly isn't simple. Double glazing might make a difference to our 2k heating bill but I have a feeling the window draughts are just one small part - what about the open fires, the gappy floorboards over earth, the front doors that have a 1/2 cm gap all round? An old house just isn't a sealed thing.

 

[AMc]

Of course a new window will be worth double glazing as the incremental cost of the sealed unit over a sheet of float is so small in the overall scheme of the endeavour. My new glazing is all sealed units with soft coating and argon fill my few original windows have been secondarily glazed to meet 2006 building regs.

It used to be advocated by some that it was "worth" ripping out serviceable windows to put in double glazed ones because of the energy savings - I believe that this is one of the reasons that "double glazing salesmen" got such a lamentable reputation.

 

[biffvernon]

The other reason was uPVC.

 

[Penners]

The additional reason is double glazing salesmen.

 

[Penners]

An old house just isn't a sealed thing.

And nor should it be. Ventilation is important.

Mind you, there are limits....! :wink: