Edwardian glass for windows

[paulb33]

Hi Folks,

I need to specify glass for the new timber replacement windows in my 1901 Arts & Crafts house. The windows will be single glazed, mostly side hung casements with Georgian style glazing. Number one priority is authenticity.

What should I be asking for?

Regards,

Paul

 

[Penners]

This is way outside my area of expertise (as are most things), but that's never stopped me from venturing an opinion!

By the Edwardian era, I believe there were several ways of producing window glass. So the type of glass originally used in your house might have been dictated to a large extent by what the purchaser could afford.

This information may be of some help:-

1226 – "Broad Sheet" first produced in Sussex
1330 – "Crown Glass" first produced in Rouen, France. "Broad Sheet" also produced. Both were also supplied for export
1620 – "Blown Plate" first produced in London. Used for mirrors and coach plates.
1678 – "Crown Glass" first produced in London. This process dominated until the 19th century
1688 – "Polished Plate" first produced in France (cast then hand polished)
1773 – "Polished Plate" adopted by English at Ravenshead. By 1800 a steam engine was used to carry out the grinding and polishing process
1834 – "Improved Cylinder Sheet" introduced by Robert Lucas Chance, based on a German process of partial remelting of cut glass cylinders. This type of glass was used to glaze the The Crystal Palace of the Great Exhibition. The process was common until WW1.
1843 – An early form of "Float Glass" invented by Henry Bessemer, pouring glass onto liquid tin. Expensive and not a commercial success.
1847 – "Rolled Plate" introduced by James Hartley. This allowed a ribbed finish. This type of glass was often used for extensive glass roofs such as within railway stations
1888 – "Machine Rolled" glass introduced allowing patterns to be introduced
1898 – "Wired Cast" glass invented by Pilkington for use where safety or security was an issue. This is commonly given the misnomer "Georgian Wired Glass" but greatly post-dates the Georgian era.
1903 – "Machine Drawn Cylinder" technique invented in USA. Manufactured under licence in UK by Pilkington from 1910 until 1933.
1913 – "Flat Drawn Sheet" technique developed in Belgium. First produced under licence in UK in 1919 in Kent
1923 – "Polished Plate" first appeared in UK. Commonly used for large panes such as on shopfronts.
1938 – "Polished Plate" process improved by Pilkington, incorporating a double grinding process to give an improved quality of finish
1959 – "Float Glass" launched in UK. Invented by Sir Alistair Pilkington.

 

[Feltwell]

Have you any original glass to compare it to?

Have a look at Tatra P1:-

http://www.tatra-glass.co.uk/restoration_glass.php

In my 1899 house it's noticeable that where original glass has survived, on the 1st floor it's noticeably more "wobbly" and therefore presumably was cheaper than the glass on the ground floor. Alas much has been replaced with modern float glass

 

[paulb33]

Thanks Penners and Feltwell. This is fascinating and helpful. I want to steer clear of modern flat glass. I wonder what is available and can be specified by a restorer in the UK today?
Paul

 

[plasticpigeon]

My little Edwardian (1903) terrace has very wobbly glass. Some sheets even have a few bits of dirt in them!!!! I'll take a picture. Greenhouse glass sometimes has a ripple or 2 if you want a cheap alternative, but is nowhere near like the original stuff.

 

[Penners]

If it were just a small window in a door, or some such, then I reckon horticultural glass would be perfectly good. However, for windows it's rather thin and fragile.

If you want to be as authentic as possible, I should go with Feltwell's recommendation.

 

[plasticpigeon]

I did look at the restoration glass, but it is expensive, and the sheet size is limited. I remember I couldn't get a big enough sheet for my bay window. Horticultural glass is 3mm, which I believe is around the same thickness as much of the glass from the early 19th century. It is good to use in sashes as it doesn't make them any heavier than the originals so the weights still balance (or so I have found).

 

[Penners]

Paul says that authenticity is the number one priority, so I imagine that this takes precedence over cost, for him.

 

[88v8]

Another vote for Tatra.

Ivor

 

[Feltwell]

Just a pain that Tatra only seem to be in Loughborough. Has anyone found any other outlets for their glass?

Usually I like to take a sash along and get the glazier to cut the glass. Some of the sashes I've got require very accurate cutting, the rebate the glass sits on is very narrow, and as with many old windows they're not always square (especially the ones with an arched top :wink: ).

I looked at horticultural glass in my local glaziers, it was near-perfect flat and fault-free. On my last window I ended up putting float glass in as I couldn't wait, once the window was in I realised it had a fault running right across the middle of the pane!

 

[OriginalGlass]

Tatra come highly recommended from this corner too. Very helpful guys.

P1 is the "oldest look" newly manufactured glass available as far as i'm aware, it is indeed wobbly but also contains quite a lot of bubbles and floors which give it a very authentic look, its thickness varies quite a lot across a stock sheet, anywhere from around 4mm to 2mm. The max stock sheet size is around 1m by .8m I believe.

Horticultural glass used to be a good alternative but the quality and flatness seems to have improved too much of recent!

Tatra also do a machine drawn which has quite a nice wobbly look but doesn't contain the bubbles and floors found in the P1, quite nice to work with as fairly consistent in thickness good to cut and available in a bigger stock sizes, easier price to swallow too!!

 

[OriginalGlass]

Evening Feltwell, where are you located? We usually only manufacture the P1 and Machine drawn in to thin sealed units but we could probably make an exception.

We're based in Ely north of Cambridge if this helps? Often the best way is to make up a template from either ply or a stiff card and courier it so we can have the glass cut ready and waiting for you to collect. I would need to check stock depending on the quantity you require.

Sorry just editing this as I noticed your location is on your post, we're much further away than Tatra!!

 

[Feltwell]

Nice offer, thank you OG, but as you say I'm closer to Tatra!

Machine drawn could well be a better bet for me, if P1 is indeed that wobbly and with that many flaws in. My original windows have some bubbles etc but not many. Even better if it's cheaper.

I could really do with finding somewhere local that sells the cheap Eastern European greenhouse glass................ if such a product exists any more.

 

[Penners]

Just a pain that Tatra only seem to be in Loughborough.

A pain!! Geddit? A PAIN...... :lol: :lol: :lol:

No? Oh well.....

 

[plasticpigeon]

That reminds me of the old joke:

Did you hear about the glass blower who inhaled by mistake?
He got a pane in his chest.

 

[Penners]

I saw right through that one.

 

[paulb33]

The glazing firm came round with 3mm DREST restoration glass. Its 160 pounds versus 30 pounds for standard float. BUT, they have a minimum charge per pane that seems to make it more competitive. The small Georgian panes are roughly 30 quid versus 20 quid (DREST versus Float) puttied in with linseed putty.

Thoughts?

P

 

[Penners]

My only thought is that, if someone is trying to charge £20 for a small pane of float glass, they are, in the immortal words of Arthur Daley, "'avin' a giraffe"!

 

[paulb33]

My only thought is that, if someone is trying to charge £20 for a small pane of float glass, they are, in the immortal words of Arthur Daley, "'avin' a giraffe"!

Thus, making the Drest look reasonably priced....

 

[OriginalGlass]

DREST is machine drawn which is effectively horticultural, not a particularly expensive glass to source and certainly not £160m2. This will appear wavy but won't have the bubbles and floors that occur within hand made.

You should be able to get Hand Made P1 cut to size for around £160m2.