Hey all I'm desperately in need of some help. I have just taken off and re-rendered the front of my house and in the process, a keystone over a window came down. Its now in two pieces (which I can overcome once its up) but I don't know how to fix it back up. It seemed to be held up previously just by the grace of god and a breeze. I heard a rumour that lots of gripfill would do it, but I'm sceptical! Its three storeys up, so please be confident in your answers, lest I be sued by a poor passer-by! Thanks alot Nix
It should be tapered, so it wedges in? if its not you will have to mechanically fix it --not gripfill.
I would recommend you get hold of this stuff http://www.ilpa.it/eng/prodotti.php?page=product&cat=2&id=21 you will need to pin the broken bits together with the glue and then pin the keystone in position. Use stainless steel pins. If you do decide to use the glue, go for the vertical as it is not as runny as the horizontal (all will become clear when you click on the link)
Isn't a keystone the lynch-pin, (literally), of a self supporting arch? Is it wise to glue it in with a bit of old jollop, Italian or not?
Yes the keystone is the lynchpin as you rightly say. I think the question though is why did it come out in the first place before we get into the realms of repair. I have however offered a method of repairing the stone and a method of preventing it falling forward if indeed that is how it came out. That jollop as you so eloquently put it Big Jules is top gear for stone repair and fixing.
Hey, thanks for all your replies. I think I have gotten confused as to my idea of a 'keystone' as it is definately not anything 'lynch-pin' like! It seems to be only for decoration, there is a proper brick lintel behind it and they are not connected in any way at all. I think it is made from some sort of plaster, but it is quite heavy. Does this make it any easier?? Cheers!
How about some good old fashioned epoxy and drill, plug and screw while the epoxy sets. Counterbore the holes in your "plaster" embelishment and fill with similar.