Measured Building Survey for Homeowners: When You Need One and What to Expect
If you're planning an extension, a renovation, or a loft conversion, you will need accurate drawings of your property's existing condition. This guide explains when a measured building survey is needed, what it involves, and what it costs.
When Do Homeowners Need a Measured Survey?
| Situation | Required? | | --- | --- | | Planning permission application | Yes — mandatory | | Rear / side / loft extension | Yes — first step | | Major renovation (structural changes) | Yes | | Property conversion (house to flats) | Yes | | Permitted development notification | Yes | | Rights of light assessment | Yes | | Minor cosmetic updates | No |
Measured Survey vs RICS Home Survey
| | Measured Building Survey | RICS Home Survey | | --- | --- | --- | | Purpose | Accurate dimensions for design and planning | Property condition assessment | | Output | CAD/PDF floor plans, elevations, sections | Written condition report | | Equipment | Laser scanners, total stations | Visual inspection | | For planning? | Yes | No | | For buyers? | No | Yes |
A RICS Home Survey (Level 1/2/3) assesses the condition of the property. It is not suitable for planning applications. A measured building survey focuses on dimensionally accurate drawings. You may need both.
What Does a Measured Survey Involve?
| Stage | What Happens | | --- | --- | | Booking | Provide address, approximate size, survey purpose | | Site visit | Surveyor measures every room, elevation, and level (3–8 hours) | | Drawing production | CAD drawings produced from scan data (3–7 working days) | | Delivery | DWG files + PDF drawings sent by email | | Review | Check drawings — flag any discrepancies |
What Do You Receive?
| Deliverable | Description | | --- | --- | | Floor plans | All floors — room dimensions, walls, doors, windows | | External elevations | All four sides | | Cross-sections | Ceiling heights, floor levels, stair geometry | | DWG files | AutoCAD — for your architect | | PDF drawings | For planning submission |
2025 Measured Survey Costs for Homeowners
| Property Type | Cost (ex VAT) | | --- | --- | | 1–2 bed flat | £350–£700 | | 3–4 bed house | £500–£1,200 | | Large / complex house | £1,000–£2,000+ | | London average | +20–30% on UK average | | 2D drawings (per drawing) | From £375 | | 3D BIM model | From £550 |
What to Do Before the Surveyor Arrives
- [ ] Clear access to all rooms — move furniture blocking walls
- [ ] Arrange keys for all doors and any locked areas
- [ ] Confirm loft / roof access — hatch accessible?
- [ ] Note any specific features to capture (fireplaces, cornices)
- [ ] Inform surveyor of any areas that cannot be accessed
Frequently Asked Questions
Q: Can I use estate agent floor plans for planning?
No — Local Planning Authorities require professionally measured drawings from a RICS-regulated surveyor. Estate agent floor plans are not acceptable.
Q: Do I need a measured survey for a loft conversion?
Yes — planning applications require existing floor plans and elevations, roof plan, and sections showing ceiling heights and floor levels.
Q: Do I need a measured survey for a rear single-storey extension?
Yes — you need existing floor plans and elevations showing how the extension relates to the existing building.
Q: What's the difference between a measured survey and a RICS building survey?
A measured survey produces accurate dimensioned drawings. A RICS building survey assesses property condition. For planning, you need the measured survey.
Q: Can the survey be done while I'm living in the property?
Yes — laser scanning is non-intrusive and works around furniture and occupied spaces.
Q: How long does the whole process take?
Site visit: 3–8 hours depending on property size. Drawing delivery: 3–7 working days. Total: 2–3 weeks from booking.
Q: Do I need a measured survey for permitted development?
Yes — permitted development applications under the 4-day prior approval process still require existing condition drawings showing the building's current state.