# Forum Home Renovation Rendering  Re creating/repairing californian bungalow render effect.

## Ramoun

Hi, 
I'm about to under pin the front facade of a californian bungalow as the original foundations where only a few bricks placed level on the ground over the last 80 years its sunk and moved etc. and there are large cracks that need to fixed. The finish on the brick it looks like a render that has 3 mm gravel in it. So the finish is rough and bumpy. as per the photo's. 
Does anyone know how they would have done it originally, and any suggestions as to how I can repiar it so it looks original. ie recipe, application etc. Any help would be greatly appreciated.

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## autogenous

Picture!!! Picture!!! Picture!!!  :2thumbsup:

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## pawnhead

G'day Ramoun 
What you've got there is called a 'stipple coat', and it's applied using a texture gun which has a crank handle, and flexible metal fingers inside, which make contact with a bar that runs across the machine. You fill it with mortar, the fingers pick up some of the mortar on their rotation as you turn the handle, and when they hit the bar, they bend over until they clear it, and then they rapidly flick forward towards the opening of the gun, spraying the render on the surface giving a random lumpy finish. You can adjust the position of the bar, which affects the amount that's sprayed by each finger, hence you can adjust the density of the texture to match what you've got there, although yours looks like it's quite smooth from having a lot of paint applied over the years. 
You have to mix pozzolanic fly ash in with the cement , renderers sand, and water. This makes the render denser, less porous, and gives it more strength so the lumps won't fall off as easily. I believe that some renderers may also use plasta masta, or lime in the mix as well. I'm not a renderer and I don't know the exact ratios and composition, but I know that a good tradesman will add fly ash to that sort of texture finish. If I had to guess, then I'd use four parts sand, one part cement, and half a part fly ash. The amount of water used would affect the texture as well. Hose the wall so it's damp, (but not absolutely saturated) before applying.  
That finish was quite common some time ago, and I've worked on quite a few jobs where we had to match it. There may be some renderers who will tell you that they can get a reasonable match with a stipple brush, but it won't look exactly the same. What you've got there has been applied with a texture gun, and an experienced cement renderer should have one of his own.  :2thumbsup:

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## Ramoun

Thanks John, I'd never heard of one of these guns. Where these around in the 1920's when they put the finish on originally. The areas I have to touch will be from underpinning work I'm about to start. 1ft sq areas of delamination and lots of 10mm cracks etc.  I also found a patch that had never had paint on it, and also sand blasted a small section to see what was underneath. All the bumps appear to come from small gravel (blue metal). Picture attached. The stipple brush is a good idea but I think it will be to fine.   Cheers Ramoun

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## pawnhead

> Thanks John, I'd never heard of one of these guns. Where these around in the 1920's when they put the finish on originally.

  I'd imagine that someone would have manufactured them since the texture was quite popular, and I still think it looks good when applied to the right style of house (I've seen old ones made of galvanised iron). I'd also imagine that a few tradesmen would make their own. At close to $200 for that chunk of plastic with a handle and a few spring steel teeth, I'd certainly have a go if I wanted to save some money.  
Make a wooden box, or get an old plastic 5 litre oil container that already has a carry handle, and cut a hole for the opening. Get a thick PET juice bottle and cut finger strips about 10mm wide and about 200mm long from it (you may need to glue two strips together to make the fingers stronger and springier). Get four sticks of timber 10mm square, glue and screw two together with the fingers in between, leaving 10mm space between the fingers, and leaving the fingers sticking out about 100mm on each side of the sticks. Glue and screw the other two sticks to the first two, whilst installing more fingers in the spaces between the first lot, but perpendicular to them. You'll have a square axle that has fingers sticking out in four directions, with 10mm spaces between the fingers (if you can't picture it, I can do a quick sketch). Drill some holes in your box/oil container for the axle and insert it. screw and glue a stick of 2 X 1 at 90 degrees to the end of the axle. Drill a hole in the end of the 2 X 1 and insert a small bolt, or a piece of coat-hanger wire for a handle. Screw another stick across the inside of your box, above the fingers for them to bend against, and flick off from. Screw it from the outside, and adjust it either closer, of further away from the axle to achieve the desired effect. If I had all the junk at the ready, then I reckon I could knock one together in short shrift. Of course it wouldn't be as durable as a proper one with stainless spring steel fingers, but durability isn't an issue for a single use gun.   

> The areas I have to touch will be from underpinning work I'm about to start. 1ft sq areas of delamination and lots of 10mm cracks etc.

  If you only had to do a little, then it might be worth while having a go yourself. A renderer won't be that cheap (if he could be bothered with such a small job in the first place) since he's got to pick up his material and drive to the job, possibly buggering up his day elsewhere. It's sometimes hard to get motivated to do more than one job in a day, so he might sting you for more than a few hundred bucks.  
The small cracks I'd just gappo up unless it was de-laminating, but if they're 10mm, then it would be tricky. You'd have to try to wipe off the excess from the existing work or you'd get a hump. It might be easier daubing it in with a stiff brush and mucking around with your fingers (with good dish-washing gloves on). 
If you're getting an experienced painter on the job, then there's just a chance that he may have a texture gun.   

> I also found a patch that had never had paint on it, and also sand blasted a small section to see what was underneath. All the bumps appear to come from small gravel (blue metal). Picture attached. The stipple brush is a good idea but I think it will be to fine.

  Yeh, like I said, I'm not too sure of the composition, but you're right that it probably has some course river sand, perhaps in place of the renderers sand (it's a very gritty sand that has tiny bits of gravel through it, depending on where it's from). I could inquire from a friend of mine (who does all my rendering) if you'd like. He's Yugoslavian, and along with Italians, Greeks and the Poms, they're usually the most experienced at the trade.  :Cool:  
A stipple brush won't give you the same lumpy effect.  :No:  
Edit; It would probably help to apply some diluted bondcrete (or PVA glue if you've got some) to the wall before applying.

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## Ramoun

Thanks John, 
I just saw your post and had already started to manufacture one the oil container is good idea.  I'let you know how it goes.  Does anyone know what the recipe is. 
Cheers

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## myla

hi, 
you can get the machines from Mitchel Building Supplies in richmond/burnley 
the mix is typical render (3 wash sand, 1 lime, 1 cement and boncrete in h2o) 
but seriously, if you only patching small areas you would probably do it by using a splash trowel (small rounded/or square trowel, like brickies) 
so just throwing it onto the surface, prewet surface as you go 
thanks

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## autogenous

flick it with a brush with the mortar at a particular texture. 4:1:1 
You can buy stucco boxes with flickers in them at plasterers tool supplies. 
I cant recall the name of them at present. Something Italian.  
They look like a jewellery box player with blades that flick the mortar onto the wall. 
Monkey box is the slang term.  
It sending me nuts trying to remember the name. 
It looks like pebble dash of some form you have there.

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## zoj

Hi guys,
I stumbled on this thread and would like to ask how one could possibly remove this "stipple" effect .
Recently got a Cal. Bung. where some interior walls have this finish and would very much like to smooth it off so the kids dont go hurting themselves.
Not unlike the photos above,the paint finish is kind of glossy.Is it possible to skim over this somehow or would you need to really etch it back and replaster?
Any help would be appreciated..cheers.

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## myla

hi, 
yes you would to need to "rough up" gloss, 
as its inside dust/mess is going to be a huge problem 
know either do with chisel bit in drill or by hand 
thanks

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## Ramoun

Thanks Guy's, 
I found a plasterers stimple box in Richmond and fluffed round with the mixture for a few days to get it close to right.  After a couple coats of paint you cant pick the repairs. 
Next job is the cellar and excavating under the house. 
Cheers
Ramoun

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