Nooooo! Use proper building sand from Jewsons or even B&Q. No wonder it fell to bits!

you need coarse building sand to mix with cement, play sand is washed and treated so it doesn't ''bind''

do NOT use it for building purposes

only for play mortar....it will work good for play houses

I am new to this, I mixed 3 parts playsand with one part Cal porland cement type II/V. wet clay like consistency. When it dried, it crumble into powder again. What is the error? please help, thank