You should consider a Level 3 Survey (often described as the most detailed RICS home survey) when the property, your plans, or the visible condition suggest there’s a higher chance of costly surprises—and you want a report that goes beyond a simple condition snapshot and gives deeper, practical guidance on defects, causes, repair options, and future maintenance.
RICS’ consumer guidance notes that the right survey level typically depends on the property’s age, size, condition, complexity, and originality.
A quick rule of thumb
A Level 3 Survey is usually the right choice if you’re dealing with any of the following:
- Large, older, or run-down properties
- Buildings that are unusual in design or altered
- Purchases where you’re planning major works (renovation, reconfiguration, extension)
If the property is fairly modern, conventional, and appears in good order, Level 2 may be enough. But if you’ve got uncertainties, Level 3 is the “belt and braces” option.
1) Choose Level 3 for older or character properties
Older homes often look charming, but they can come with more complex construction, layered historic repairs, and performance quirks (movement, breathability, damp behaviour, roof structure changes over time).
A Level 3 Survey is commonly recommended for:
- Victorian / Edwardian / Georgian homes
- Period cottages and farmhouses
- Older conversions (e.g., a flat created within an older house)
RICS’ “Helping you choose the right survey” guidance explicitly points Level 3 at older properties (particularly where they’re large or run-down).
2) Choose Level 3 if the property is unusual or non-standard
If the building isn’t “typical brick-and-tile”, the risk of hidden issues and specialist repairs can rise quickly.
Examples include:
- non-standard wall construction (e.g., certain concrete systems, unusual cladding arrangements)
- complex roof forms (multiple valleys, dormers, large flat roof areas)
- homes with basements or significant retaining walls
- unique self-builds or heavily engineered structures
RICS notes Level 3 is appropriate for buildings that are unusual or altered.
3) Choose Level 3 if there have been significant alterations
Alterations can be absolutely fine—if they were designed and executed properly. The issue is that alterations introduce unknowns.
A Level 3 Survey is especially sensible if you see or know of:
- major extensions
- open-plan knock-throughs (removal of internal walls)
- loft conversions
- garage conversions
- structural reconfiguration or “developer refurb” where finishes can conceal defects
RICS positions Level 3 for buildings that are altered and where you need more detailed information about the structure and fabric.
4) Choose Level 3 when there are visible warning signs
If you’ve noticed anything that could point to a bigger underlying issue, Level 3 is often the more proportionate choice. Typical red flags include:
Damp and moisture indicators
- staining, mould, musty odours
- blown plaster, salt deposits, recurring redecorating
- leaking gutters/downpipes and saturated masonry
Movement indicators
- stepped cracking in brickwork
- diagonal cracks around openings
- doors/windows that stick or don’t align
Roof concerns
- visible sagging lines
- slipped tiles/slates
- ceiling staining
A Level 3 Survey is built to give more thorough and detailed reporting, including defects, remedial options, and future maintenance issues.
5) Choose Level 3 if you’re planning major works after purchase
If you intend to renovate, a Level 3 Survey can help you avoid the classic scenario where your refurbishment budget gets blown up by issues you only discover once you start opening things up.
RICS describes Level 3 as suitable if you’re planning major works.
What makes Level 3 different in practice
A Level 3 Survey is generally described by RICS as being more thorough and detailed, addressing:
- materials used for each part of the building
- defects and remedial options
- issues related to future maintenance
It also typically inspects certain “normally opened/used” concealed areas where safe to do so and observes services in normal operation (without specialist testing).
When Level 3 might be unnecessary
You may not need Level 3 if:
- the property is modern and conventional
- condition appears good
- there are no major alterations
- you’re not planning significant works
In those cases, Level 2 can be a good balance of detail and cost.
A simple decision checklist
If you answer yes to two or more, Level 3 is often the safer pick:
- Is the property 100+ years old (or clearly period/character)?
- Has it been extended/structurally altered?
- Is it non-standard or unusually built?
- Is it run-down or in need of updating?
- Have you seen damp, cracking, or roof concerns?
- Are you planning major renovation works?
Want a clear recommendation for your property?
Email mail@howorth.uk or call 07794 400 212 and tell us the property type/age, whether it’s been extended or altered, and any concerns you’ve spotted. We’ll guide you on whether a Level 3 Survey is the sensible choice—or if a Level 2 will do the job.