Great comments Clive, you answered my query with respect to the 100mm joists, any dimension can be used in this instance although I always refer to the Span tables. I usually stick with the bigger the better and for the cost savings from 150 to 100 dimension joists wouldn’t really make a saving worth worrying about due to the increased amount of the beams that would then be required and also posts…
I can’t comment upon the TDCA’s want for a 3kN Loading, this doesn’t match with TRADA, I would rather use the qualified direction via the span tables promulgated by the eminent Dr’s of wood science in house at TRADA after all they wrote the regulations to include EC5.
I shall ask Janet from the TDCA for her comments.
Karl