"John Rumm" wrote in message
...
Andy wrote:

As I understand it roughcast involves making up a sort of concrete made
with small aggregate (3/8" down to sand size ) and flinging it at the
undercoat of render.

How rough do you want your roughcast?

The much of our place is finished with a roughcast / stipple render, and
when I was doing the new gable end for my loft conversion I wanted to
match it. I found I was able to get an almost perfect match by simply
rendering the top coat as normal, then then giving it a firm tamping all
over with a stiff dustpan brush.

see bottom two photos on this page:
http://www.internode.co.uk/loft/rendering.htm

Anyone done this? Any tips? I figured on getting a small fire shovel,
loading that up and flinging it from a great distance, varying the angles
of application to get an even finish, sounds good in theory but what
about in practise. I'm worried the roughcast will bounce off*, presumably
I may need a thin (1/4"?) topcoat render layer to fling it onto, and I'm
going to try and keep that wet by spraying, so the roughcast sticks.

I thought I might try limewash as a finish.

One thing I found is that new rough render is a PITA to paint!


--
Cheers,

John.

Thanks for that John, I'm impressed, that looked like a big job!
It's not easy to tell how much texture you achieved from your photos, but
I'm looking for quite a lot, so I may try the roughcast route and see how it
goes.

I've had problems already, listened to a neighbours advice, and left the
battens on overnight: of course when it came to pulling them off I pulled
off/blew quite a bit of the render undercoat. I had to go around tapping the
render with my knuckle to find the detached areas and chop them out and
renew. He also said that I didn't need to scratch the undercoat as the
texture from using a wooden float on it would be enough to give the topcoat
a key, but I'm thinking he speaks with forked tongue now!

I think I will practice roughcast on a piece of plasterboard. For the
curious, my wall has exposed red brick-and-a-half piers capped with a thick
( 4.5" ), flat-topped cast concrete coping painted white, blockwork finished
( hopefully ) with roughcast ( limewashed ), and the wall finished with 1.5"
Welsh slate coping.

Andy.