Replacing stone mullions

[RedB]

Hi - this is my first post of what I suspect will be many. We have recently had our offer accepted on an Edwardian house (well the details say Victorian, the surveyer says Edwardian) which needs a substantial amount of work doing to it. Although we have renovated a Victorian terrace, we have not done anything of this scale before so I'm trying to get as much info as I can. So my first question is about stone mullions - the structural survey said that they need replacing as they have some kind of ferrous core which is starting to rust (I am paraphrasing there, but I think that's essentially what he said, don't have the final report yet) This may be a "how long is a piece of string" question, but can anyone give any guidance as to how much it might cost? I can show a picture if I can work out how to paste one in!

Thanks
Red

 

[middi]

Mullions are ,usually, made to order by stone masons, these are the people that can give you an accurate cost. What you have at present is ,most likely, pre-cast type, hence the rusting metal. Check your local aerea for stonemasons.

 

[chuckey]

A lot of Victorian stone work is Ham stone, this is an artificial concrete based stuff, coloured buff/yellow. I made some matching lintels for my place by building formwork, complete with built in chamfers. It was well finished (sanded etc) then painted with two coats of emulsion and wax polished. I tried 5 different mixes of say a cupful of each with yellow concrete dye from Wickes, labelling them as to what they contain. Once I had got the right colour, I proceeded to mix and pour. Be very careful with your tamping on the visible sides and edges. One area I cocked up, about 4" long X 3" high in a frontal surface of 12' X 9". Still looks OK.
As a general point, Mullions are pillars and are under a compression load, so putting a piece of steel in their centre does not seem worth while unless its a substantial tube say 2" diam, which takes the load, the covering serving only to make it pretty. Traditionel stone mullions do not contain steel.
Frank

 

[Nemesis]

Mullions can be drilled and a metal rod placed in the mullion and in the stone it 'attaches' to. Over time it's perfectly possible that any protective line of mortar erodes and water ingress ensues, thus making the metal corrode and expand and damage the stone. Is there a great deal of visible evidence of this?

Ham stone:

http://www.visitsouthsomerset.com/index.jsp?articleid=12160

Mostly 19th early 20th c stone is just that - stone. There may be some artificial Coade type stone or terracotta - and some early ferro-concrete - but most likely it's real stone. It's not hard to tell the difference.

 

[Jon Maine]

Ham stone comes from Ham hill near Yeovil, Montacute House is Ham.

Iron cramps, pins or dowels have been used to fix masonry together in the past I suspect that this is what you have.

Once you establish the nature of your ironwork which will be rusting, expanding and blowing the stone apart you could get a specialist to cut out some slots, remove the iron, replace with stainless steel and resin and let a piece of stone back in or alternatively do a stone dust lime mortar patch repair.

I would be suprised if you needed to change the lot.

Pictures?