# Georgian glazing bars?



## leverb01507 (8 Jun 2010)

What joining technique do you use where horizontal and vertical glazing bars meet and where they come in to contact with the main frame of the sash, this is for single glazing, p.s. pictures would help.
thanks
Ben,


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## Tim Nott (8 Jun 2010)

Scribed mortise and tenon. Gets complicated when the depth (ie inside-to-outside) of the glazing bar is less than the stiles and top/bottom rails


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## chipchaser (8 Jun 2010)

Hi Ben,

Drawings of tenoned joint, As described by Tim. I think this is the more usual type. Also a halved joint which I have not come across myself.

The rectangular glazing bar is not the flattened ogee or cyma “Georgian” pattern as most commonly found. These examples come from a text book first published in the 1940’s but early sashes also had plain rectangular sections











Also a photo of one of the sashes I have been repairing. As you can see in this example (from 1895) the top rail has been cut at 45 degrees to partly accommodate the end profile of the glazing bar. The flattened ogee or cyma moulding has been mitred rather than scribed to fit the glazing bar into which it is too be tenoned as shown in the first drawing.






Photo also shows what can happen when you don’t find the wedge in the tenon.  Every other joint had two wedges, one either side. I was caught out but actually it would have made no difference if I had found and removed it as the tenon was set in its spread position and even when I cut the wedge out I couldn’t press the timber back to its original form. I think I would have had to steam it first. All repaired now and my error hidden  

Graham


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## Loz_S (8 Jun 2010)

Nice drawings! Which text book are they taken from?


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## SNight (8 Jun 2010)

Halved and mitred if traditional for single glazing. If they are for a modern window to accept a double glazed window, then mortice, tennon and scribed. Although you can also use plant on glazing bars over a double glazed unit to get a traditional slim glazing bar look.


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## chipchaser (8 Jun 2010)

Loz_S, Drawings are from Building Construction by W.B. McKay, Volume 1 (of 4), pub Longmans. The originals are long out of print but there are used copies about and Donhead have done a reprint of volumes 1 to 3 at £69. Mine, vols 1-3 and vol 4, by his son JK McKay, cost me 5 pounds and 17 shillings in 1967. Volume 1 was actually first published in 1938.

I think that, although limited to pre war (WWII) practice, volumes 1 to 3 cover the basics of building construction better than Mitchell’s, nicer drawings and clear text. On the other hand, Mitchell’s is far more comprehensive and relatively up to date.

If interested in old stuff, the other classics are the 3 volumes of Architectural Building Construction by Jaggard and Drury first published in the early 1920’s.

Ben, my description of the joint shown in the photo was incorrect. After posting I looked at another one in the workshop. What looks like a mitre of the moulds in the photo is actually rather cruder. The profile of the glazing bar moulding has been transferred to the moulding on the rail and the rail cut away to form a shallow housing for the end of the bar. Its just enough to look right when assembled. I guess they were paid by the piece and spent the minimum time possible. Although not as perfectly executed as we might hope these have stood the test of time and only broke down due to decay because the putty and paint were neglected in recent years.


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## Loz_S (9 Jun 2010)

Thanks for the titles. I love reading old manuals like these. I think everyone will have heard of or have a copy of George Ellis' books but I particularly like Peter Nicholson's New Practical Builder from 1825 and J W Riley's Manual of Carpentry and Joinery from 1905. Excellent old school texts.

If you are interested in vernacular architecture in general, there are some real gems hidden in the works by RW Brunskill.

Sorry for the thread drift :mrgreen:


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