How do I tell if joists in my 1946 Loft are strong enough to lay down

David Perrin

Hi as a rule of thumb if the joists are no smaller than 75mm / 3 " and you do not have any unsupported lengths of joists more than 3 Mtrs using tongue and groove panels this will be fine as the boards will add strength to the floor . I must emphasize that this is not suitable for habitation and is to be used as storage only spreading weight evenly. Regards Dave