Structural Calculations & Review

I have a single-storey residential extension ready for Building Control sign-off and my insurer’s warranty. The roof layout has already been designed by the posi-joist supplier, so what remains is a full structural check and the accompanying calcs package covering three key elements:

• Strip foundations bearing on clay soil
• A 4 m wide opening that will be spanned by a new lintel (door set)
• Interaction with the posi-joist roof to confirm overall stability and load paths

The extension carries only light residential loads, but I still need stamped calculations, concise sketches or mark-ups, and any connection details necessary to keep the inspector happy. Please reference current UK codes (Eurocode or BS as appropriate), verify bearing pressures for the clay sub-grade, size the steel or engineered timber lintel, and confirm lateral restraint for the joisted roof. A brief summary note outlining your assumptions and safety factors will round off the submission.

PDF output is fine, but an editable copy in either Tekla Tedds, Robot, Revit, or a clean spreadsheet would be a bonus for my records.