A Level 3 Survey (often called a Building Survey) is designed to cover as much of the property as is physically accessible on the day, with a careful inspection of the inside and outside of the main building, plus permanent outbuildings.
It’s a whole-property survey—so it doesn’t just look at the “nice bits” you see on a viewing. It focuses heavily on the areas most likely to hide expensive problems: roofs, rainwater goods, damp pathways, structure, floors, lofts and drainage.
Below is a clear breakdown of what your surveyor will cover.
1) The main building – outside (the external envelope)
Your surveyor will inspect the property’s outer shell because many major defects start externally and show up internally later.
Typically covered:
Roofs and high-level elements (as visible and safe)
- roof coverings (tiles/slates), ridges/hips/verges
- valleys, abutments and roof junctions
- chimneys and flashings
- visible roofline sagging or distortion
Surveys commonly involve viewing roofs and other high-level surfaces from ground level, sometimes from neighbouring public land where accessible, often using binoculars and a torch.
Rainwater goods
- gutters and downpipes (leaks, blockages, poor discharge)
- staining on walls from overflow
- how rainwater is directed away from the building (a big damp risk factor)
External walls and openings
- brickwork/render/cladding condition (cracking, bulging, spalling)
- pointing condition and weathering
- damp pathways (bridging at low level, defective seals, high ground levels)
- external windows and doors (condition, deterioration, obvious defects)
2) The main building – inside (room-by-room inspection)
Inside, the surveyor checks how the building is performing and looks for signs of movement, damp, poor workmanship, and concealed issues.
Typically covered:
Walls, ceilings and partitions
- cracks (type, location, pattern)
- bulging/distortion and poor junctions
- damp staining, mould, salts, blown plaster (where visible)
Floors and stairs
- condition and “feel” of floors (unevenness, bounce/deflection)
- visible signs consistent with damp-related deterioration at low level
In a Level 3 inspection, the surveyor will inspect exposed floor surfaces, lift corners of loose/unfitted coverings where practicable, and assess floors for excessive deflection (often described as a “heel-drop” test).
Kitchens, bathrooms and other wet areas
- moisture indicators around showers/baths/sinks
- ventilation/condensation risk markers
- signs of leakage and poor finishes (where accessible)
3) Roof space (loft) – if it’s safe and accessible
Where safe and reasonable, the surveyor will enter the roof space and visually inspect the roof structure, focusing on vulnerable areas.
Typically covered:
- roof structure timbers (condition, distortion, staining)
- evidence of leaks or condensation in the void
- ventilation and insulation observations
RICS notes insulation isn’t moved, but small corners may be lifted (if safe) so its thickness/type and the underlying ceiling can be identified.
4) Under-floor areas and subfloor ventilation (where relevant and safe)
This is especially important in older homes with suspended timber floors.
Where access exists and it’s safe, a Level 3 inspection may include:
- inspection of under-floor spaces (from hatches/void access points)
- a more thorough check of subfloor condition where safe entry is possible
Even where entry isn’t possible, the surveyor will still assess risk based on construction type and visible symptoms.
5) Drainage elements (what can be seen without specialist testing)
A Level 3 survey can include lifting accessible inspection chamber covers to drains/septic tanks where safe and without causing damage, and observing normal operation in everyday use.
This doesn’t replace a CCTV drain survey, but it can highlight warning signs early.
6) Services (observed, not “tested”)
A Level 3 Survey covers visible parts of services such as:
- electrics
- gas/oil
- water and plumbing
- heating
- drainage (visible aspects)
However, services are often concealed within the building fabric. RICS is clear that only visible parts can be inspected and the surveyor does not carry out specialist tests or assess efficiency/safety in the way an electrician or Gas Safe engineer would.
In Level 3, services may be observed in normal operation (switched/operated where safe and permitted), but not tested as a specialist inspection.
7) Outbuildings, boundaries, and the grounds
A Level 3 Survey covers more than the house itself.
Typically covered:
Permanent outbuildings
Garages, permanent sheds, annexes and similar structures are inspected (where accessible).
Boundaries and shared/common areas
The surveyor inspects boundary walls/fences and any shared/common areas, walking around the grounds and (where helpful and accessible) neighbouring public property.
The grounds
RICS notes that in a Level 3 inspection the surveyor should carry out a comprehensive inspection of the grounds, because defects in external areas can be costly and influence the buying decision.
That can include:
- retaining walls
- paths, paving, steps and drainage falls
- signs of settlement/ponding around the property
- external features that may contribute to damp or movement risk
8) If you’re buying a flat: what’s covered?
With flats, the “parts of the property” can mean both:
- the flat’s internal demise, and
- relevant shared parts (depending on access and responsibility).
In general, when inspecting flats, the surveyor assesses the general condition of the outside surfaces of the building and the access/communal areas leading to the flat (where accessible), as well as roof spaces only where access/ownership allows.
Important: what a Level 3 Survey won’t cover (because it’s non-intrusive)
Even though it’s the most comprehensive pre-purchase survey type, it still won’t “open up” the building. RICS states the surveyor won’t force or open up the fabric without consent or where there’s risk of injury/damage—this includes lifting fitted carpets/floor coverings/floorboards, moving heavy furniture, removing stored contents, removing secured panels/hatches, or undoing electrical fittings.
Want advice on what a Level 3 Survey will cover for your specific property?
Email mail@howorth.uk or call 07794 400 212 with the property type (house/flat), approximate age, and any concerns (damp, cracking, roof condition, alterations). We’ll tell you what can realistically be inspected, how to improve access on the day, and whether Level 3 is the best fit.