To pump an ICF, you need two things: a pump and concrete. Pumps cost £550 +VAT. The concrete costs what it costs.
What do you do if the company sends out concrete that's too stiff? Durisol needs to be of Scotch Broth type consistency. I'm trying to avoid wasting the poor pump driver's time, and lightening our bank balance by £550 at the same time.
And how -on the spot- do I judge what the correct slump is?
The only way I can think to get it right, is to order a small amount of concrete at XYZ slump and see if the company actually delivers it.
Concrete's interestingly tricky stuff innit? Fascinates me