Creating a repro stone door surround

[Lobster]

I'm in the midst of renovation a small terraced house, and want to reinstate the front doorway as it was originally built, with a surround like the one in the link below, to matches all the others in the terrace.

surrounds were carved stone, and ideally I'd get one from the local reclamation yard (but none are in stock and they get them in only rarely). I could get a new one carved at a cost of thousands (no thanks) so am wondering if there is some way I could make a cast cement version. I would I go about this? Could I somehow take a cast off an existing doorway (I do have access to one), then use that to make a mould? Then attach the casting to the side of the house somehow? It's really the part above the door I'm talking about; I think the sides could be done using sand/cement render.

Would some form of polymer be a better bet?

The bulk of the surround is about 0.75" thick, except for the plinth/shelf bit which is probably about 3" deep.

I'm not subject to conservation area rules or anything like that, so there's no problem not using the original materials.

Any thoughts please? Or is this idea a non starter?

Thanks David

[Christian McArdle]

My mother couldn't find someone even willing to look at her stonework which needed replacing. In the end she went for cement "fix". It lasted about 1 month. The next door neighbour but one, who is a builder, apparently sat there laughing as they did it, so obvious was the imminent failure.

Christian.

[Nick Brooks]

A company local to me makes repro "stone" fireplaces like these

are made in pieces using (I believe ) a rubber mould Acid etching removes the smooth moulded surface giving a very "real" appearance It has however taken them years to perfect the process and needs considerable space, materials and careful handling

good luck if you attempt it

N

[Anna Kettle]

Making a mould will not be easy and I'm not sure you will be happy with the result, for colour if nothing else. I'd be tempted to make one of wood which matches for size and shape and then paint it.

Anna

-- ~~ Anna Kettle, Suffolk, England |""""| ~ Lime plasterwork, plaster conservation / ^^ \ // Freehand modelling and pargeting |____|

07976 649862

[Michael McNeil]

I was of the impression that the main part of these things were made of wood and that the bottom 12 or 15 inches were slate or some such.

I can't understand why a plasterer couldn't make a fair stab at it though. You put a wide batton along one side, sticking out past the reveal an inch or so. Wet the wall -perhaps with some pva in the water. Then fill out the reveal. Do the reveal on the other side.

Next day put the battons against the reveals and have them protrude an inch or so, again. Put battons 5 or 6 inches out from the corner, wet the wall and fill the bits in between. What's wrong with that? You can knock the battons away as soon as the stuff is in place or you can leave it as long as you like.

You want a strongish mix though, as it will get some wear and tear. 4 or

5 to 1, I think?

[Dave Plowman]

When I bought my house, some of the stone mouldings that ran across the top of the bay window - just sort of plain flutes - were in poor condition. The similar ones across the door were ok, though. I couldn't find any information on fixing them - it was well before the internet.

I made a mould in fibreglass of the good part.

I chipped out all the loose or crumbly bad stone, and screwed in some galvanised screws below the final level. Gave it all a good soak in Unibond. Then made up a fairly sloppy mix of exterior Polyfilla - the old fine mortar stuff. Repaired the 'flat' edges where the mould would bare on. Had to experiment with the mix a bit - then simply slapped the mould - full of the mix - onto the damaged bits. When it had started to go off, some careful paring of the excess made a job which although not perfect is more than adequate, and better than 'decorators' repair to other similar houses in the street. And has lasted over 25 years. Of course the stonework is painted - I'd not say this would be any good on 'natural' stone, which Victorian mouldings often aren't.

[Lobster]

Mm, I was thinking of doing that for the reveal. It was really the part above the door (qv

which is causing me most head-scratching; the part that looks a bit like a crown. At present, having read the replies (thanks all!) I'm thinking of following Anna's advice on that, and try using timber.

David

[Michael McNeil]

What are you going to use for the coping?

Obviously for the top you could make a template and use rendering again.

[Lobster]

Hmm, now that's food for thought. Could you outline the process here? Do you coat the original stone surface with some form of releasing agent (what?); then just apply glass fibre matting and resin? (where do you buy the stuff in reasonable quantitities, ie more than a carbodywork repair kit's worth?

Thanks David

[Dave Plowman]

I used wax polish - the solid sort you get for floors. And I found a car kit made a long enough bit - about a foot or so is enough to handle at one time. Doing a mould of a long length would make it rather difficult to handle, as you have to exert a lot of pressure to force the mortar into place, and any excess out the ends. You then simply overlap each section before it sets. As I said, I made good the top and bottom parts of the moulding first - these were flat, so easy enough to do. This gives a reference for you to push the mould against.