Home Extension And New Staircase

I’m planning a single-story extension that will open the ground floor into a brighter living area, a modern kitchen, and a compact downstairs WC. Alongside the new footprint I also want to replace the existing staircase so the flow between floors feels seamless and fully compliant with current regulations.

Here’s what I need from you. First, a complete set of architectural and structural drawings my builder can take straight on site, prepared in the CAD or BIM platform you’re most comfortable with—AutoCAD, Revit and SketchUp all work for me as long as the final files arrive in DWG and PDF. The plans must show every detail of the extension layout, service runs for plumbing and electrics, and accurate staircase geometry. Second, visual material: a few 3-D renders so I can review finishes and make quick design decisions before anything is ordered. Finally, you should be prepared to answer the occasional question from building control or the structural engineer once the drawings are in for approval.

Acceptance criteria
• Scaled floor plans, roof plan, elevations and cross-sections (1 : 50 / 1 : 100)
• Detailed staircase drawings that meet current UK Building Regulations
• Layouts for kitchen units, appliances, drainage and the downstairs WC
• Door, window and finishing schedules plus a basic materials list
• At least three rendered views of the proposed extension
• Deliverables supplied in DWG, PDF and a 3-D model format (RVT, IFC or SKP)

If you’ve handled similar residential projects, especially single-story extensions, I’d love to see them along with your estimated turnaround time.