Final Finish - Stucco and Chicken Wire

[david s]

Re: Final Finish - Stucco and Chicken Wire

Render layers should not exceed 25mm in thickness, but you can probably get away with it. Each subsequent layer should be weaker apparently ie. less cement.

[brung99]

Re: Final Finish - Stucco and Chicken Wire

I rendered my oven a few days ago so its still in the curing/hardening phase.

All went well wit the render mix, application and finishing off.

If I wanted to lay another coat over the top of this first layer (in order to change the shape of the dome - just for the final look), would it be ok to simply mix up another batch and repeat the process just like the first time?.

I have reinforcement fibres so I'm not worried about using chicken wire. The minimum thickness I will add would be at least an inch in some spots and alot more in others.

Does anyone have experience/advice they could share with me about doing this?

[brung99]

Re: Final Finish - Stucco and Chicken Wire

Hi David,

FYI, I finished my rendering today and all went well. Thanks again for your advice.

[david s]

Re: Final Finish - Stucco and Chicken Wire

I make some wire ties which I embed in the mortar covering the bricks. They can poke right through the blanket. That's the way I do it anyway, probably too late for you. You could try wrapping wires all round the dome, then snipping the wires off where they go across the front arch after the render has set.

[hungng]

Re: Final Finish - Stucco and Chicken Wire

So... as per the original question, how do you secure the chicken wire to the dome to hold its shape?

[brickie in oz]

Re: Final Finish - Stucco and Chicken Wire

Thanks for your quick reply David. I'm rendering my dome tomorrow and am hoping I mix it correctly and it doesnt end up cracking on me, I thought the bondcrete would make it stronger and hold together better. I have some reinforcement fibres so I might go down that path instead.

Render only cracks if you use the wrong sand, ie, sand with too much clay in it.
You have to used washed sand with no clay in it.

[brung99]

Re: Final Finish - Stucco and Chicken Wire

Thanks for your quick reply David. I'm rendering my dome tomorrow and am hoping I mix it correctly and it doesnt end up cracking on me, I thought the bondcrete would make it stronger and hold together better. I have some reinforcement fibres so I might go down that path instead.

[david s]

Re: Final Finish - Stucco and Chicken Wire

Hi David,

What are youre thoughts of adding a bonding agent like bondcrete/cemcrete to the render mix ?

Yes, you could try that in an effort to make the render waterproof. Personally I prefer to make sure the thing is 100% dry by doing about 10 cooking firings and then waterproof the surface. You don't want to lock moisture in the oven when it is still moist.

[brung99]

Re: Final Finish - Stucco and Chicken Wire

Hi David,

What are youre thoughts of adding a bonding agent like bondcrete/cemcrete to the render mix ?

[david s]

Re: Final Finish - Stucco and Chicken Wire

In the trade of cement rendering of houses this may be true, it is impractical to do so, it's very difficult to wrap a whole house. Render should not be applied in full sun or on windy days, this is another one that the builders ignore. In the trade of oven building or ferrocement it is mandatory if you want the end product to turn out with sufficient strength.

[brickie in oz]

Re: Final Finish - Stucco and Chicken Wire

No one in the trade covers it for a week, yet they have no problems.

[david s]

Re: Final Finish - Stucco and Chicken Wire

Do a search on renders to help you. I use 4:1:1 silica sand, cement, lime. The addition of lime in the mix makes the brew stickier, which is great to apply, but more importantly for our application, gives it some elasticity. The downside is that the lime makes the mix slower to harden. Be sure to cover it well for at least a week to retain moisture while the hydration process is going on.

[brickie in oz]

Re: Final Finish - Stucco and Chicken Wire

If you use white sand, and white cement you can add any colour oxide you like to colour it too.

[JamesLynn]

Re: Final Finish - Stucco and Chicken Wire

Thanks Brickie, Problem solved. I'll go with my own render mix!

[brickie in oz]

Re: Final Finish - Stucco and Chicken Wire

I would use sand and cement for render myself, you seem familiar with it so go for it.
The so called acrylic renders are just a cheap fix for the volume builders, cheap and nasty, its nothing more than thick acrylic paint with some sand in it for texture.

The traditional sand and cement render has stood the test of time which I doubt the acrylic render will do.

If mixing sand cement render make sure you get washed sand as sand with too much clay in it just doesnt cut it.