This calculator only works out deflections up to 25mm Downward deflection
25mm Isover APR
50mm Isover APR
25mm Knauf Earthwool APR
50mm Knauf Earthwool APR
25mm Superglass APR
50mm Superglass APR
Taped & Jointed
The quantities given make no allowances for wastage.
This information is given for guideline purposes only and it is the
responsibility of the user to ensure quantities are correct.