Existing Dry Stone Retaining Wall

[gjb]

Hi
I have an existing dry stone retaining wall. it is very poor shape and over the years the amount it is retaining has increased. I propose to remove the existing dry stone retaining wall and replace it with a reinforced concrete retaining wall and face it with stone. My question is can I build the stone back to look the same as it did before I demolished it. ie I want the concrete retaining wall to be clad with stone to look as if it is dry built stone wall. I assume you can 'partially mortar the stones' ? The existing wall has the stones laid vertically, so I want to have this on the new wall. I am give it to a contractor to do so I want to specify exactly what he has to do with the stone. Any help greatly recieved. The max height of the wall is 1.85m (6ft)

picture attached of the best section of the wall

Thanks.

[Nigel]

The best way in my opinion is to build it as a drystone wall and get the cement in the back of the stones, so lay each row, then cement the back then the next row, if the stones are placed correctly and wedged as a dry stone wall should be the cement should only add to the strength.

You need to make sure there are going to be plenty of ties coming out of the breeze block wall to keep the face from coming away. Also, what stone is being used? make sure the builder uses a mix of cement that is softer than the stones being used or the stones wont last long.

I hope that helps and that everybody kind of agrees, even though this is not really the place to discuss the use of cement

[david perry]

I'd largely agree with Nigel. Its a simple job I've done many times.

Ties to the structural wall are fairly important but as its only a few fet tall without them it should still be ok.

You should have a foundation for the stone otherwise it will crack/come away from the concrete backing wall eventually.

The neatest way of gettting an even face - if you want it, is to estimate the largest depth your stones will make and mark off a similar length of wood as a depth guage which can be used against the backing concrete.

A weakish mix 1:6 of cement & sand will be fine and build the stones in, putting the mortar at the back only. To avoid the mortar oozing out or staining make the mix dryish. It should have the same consistency as crumble (as in a crumble pie!!). In the mixer it should still be dry enough that it is not all one slurry mix but just looking rather loose and crumbly. To test it you should just be able to make it just snowball in your hand. If your hand gets wet and cement stained its too wet.

If cement does show, as it sometimes does, then a 1" paint brush can be used to brush out the joints AFTER the cement has started to dry. If you do it immediately you'll end up dragging cement over the face of the stones and get staining.

If it's going to rain in the next 24 hours, cover the work up to prevent cement leaking all over your nice work.

[jerryg]

Since the majority of all retaining walls are dry stone, why can't you rebuild it as a dry stone revetment wall?

[waller 69]

this might sound daft but i have 2 questions for you. what are you trying to hold back[if its soil it fairly easy but if its trees or the north face of the eiger it gets more complicated. second... can you wall like that? ,if not you need to find someone who can[tip dont advertise there are best kept secrets everywhere].good wallers are like family gewels, they only come out on special occasions[cash helps unless your infernal reveneu]