Your architect is quite correct. While the architect will design the building and show the position and indicate size of steel or glulam beams, wall thicknesses, pier positions and so on based on his experience, he is prevented from giving you structural calculations by his professional indemnity insurance unless he has an engineering qualifi cation as well. Most architects will advise that you will require the services of an engineer and that this cost is outside the architect’s commission. Usually the architect works closely with one or two engineering practices and will happily liaise with them on your behalf. On receipt of the calculations, the architect’s drawings should then be updated with the correct sizing of components and any other engineer’s requirement to ensure that the drawings are clear for the contractor and Building Control. The calculations will then be submitted for approval along with the plans.