Clay Render Thickness

Earth render ( clay binder) is usually recommended to be not less than a total of 50mm thick.
reinforced or stabilized earth render may achieve a good result with 35 -40mm thickness.

the type of render gun you have indicated will require your render mix to be rather runny, equating to many coats in order to acheive the required thickness. I have heard of one person applying 9 coats of render using a similar device. 2 thick coats sprayed on by a Pump , and the final coat ( 3-5mm thick) by hand is our usual method.

note some texture coat pumps or rotor and stator type pumps , will not cope with even small stones in the mix.
regards Lance Kairl House of bales.