How long between render layers?

[microbe]

Since finishing the oven proper in mid December, I have had a bunch of fires including 3 pizza parties. There is no more steam coming off the perlcrete insulation layer so I have rendered about 1cm thick including the addition of chopped basalt reinforcing fibre.

After 72 hours wrapped in plastic the surface is nice and hard and kind of rings when I knock on it. It sounds strong.

Any suggestions on how long to wait before I do the final render layer?

[fox]

You dont say what you have use for render but if it is sand and cement then then the second coat can be applied as soon as the base coat has set.
Normally that is within 24 hours, after 72 hours the base coat will have set hard and the second coat will not adhere so well as if it was still green (just set)
However I dont know what mix you used or if you left a rough surface (scratch coat) or what the weather is like…ie warm and humid, cold and dry?

[microbe]

You dont say what you have use for render but if it is sand and cement then then the second coat can be applied as soon as the base coat has set.
Normally that is within 24 hours, after 72 hours the base coat will have set hard and the second coat will not adhere so well as if it was still green (just set)
However I dont know what mix you used or if you left a rough surface (scratch coat) or what the weather is like…ie warm and humid, cold and dry?

Thanks for the reply: the mix is 3:1:0.5 Sand, cement, lime.

Yes, I did leave a nice rough surface. Weather in Sth East Queensland is warm and humid, very little rain. The render still seems to be giving off a little heat.

I will add the next layer tomorrow.