Survey jargon decoder

ArtexKeep an eye on it

Textured coating popular from the 1960s to the 1990s. Pre-2000 versions can contain a small amount of asbestos, so test before sanding or scraping.

Typical cost: £1,500–£7,000 to skim over a house

Article 4 directionKeep an eye on it

A local rule removing specific permitted development rights in an area — often for windows, doors or front elevations. Check before assuming you can change anything.

Asbestos-containing materialsKeep an eye on it

Common in anything built or altered before 2000 — artex, floor tiles, soffits, flue pipes, garage roofs. Safe if undisturbed; a licensed job if not.

Typical cost: £400–£6,000 depending on type and location

Benchmark certificateFor information

The commissioning record in the back of a boiler manual. Without it filled in and signed, manufacturers can refuse warranty claims.

BondingKeep an eye on it

Green-and-yellow earth cables tying gas and water pipework to the electrical earth. Cheap to add, and commonly missing in older houses.

Typical cost: £250–£700

BRE crack categoryFor information

The standard scale for wall cracking, 0 (hairline) to 5 (structural). Categories 0–2 are cosmetic or easily filled; 3 and above need a professional opinion.

BridgingNeeds attention

Something lets moisture bypass the damp-proof course — a raised path, a flower bed, render carried down past it. The commonest cause of "rising damp".

Typical cost: £600–£3,000 to lower levels and form a channel

Build-over agreementFor information

Consent from the water authority to build over or near a public sewer. Needed far more often than people expect on rear extensions.

Typical cost: £350–£1,200 plus any diversion

Bulging or bowing wallNeeds attention

A wall leaning out of plumb. On older solid walls this is often historic and stable, but it needs an engineer to say so.

Typical cost: £3,000–£20,000 if restraint is required

C1 (electrical)Needs attention

Danger present. Risk of injury. The electrician should have made it safe before leaving.

C2 (electrical)Needs attention

Potentially dangerous. Needs remedial work — but that is often a new consumer unit and some bonding, not a rewire.

Typical cost: £300–£2,000 typically

C3 (electrical)For information

Improvement recommended. Not a fault. An installation with only C3 items is satisfactory. Plenty of buyers have panicked over one.

CaveatFor information

The wording that limits what the surveyor is responsible for. Read the caveats before the findings — they tell you how much of the building was actually assessed.

Cavity wall insulation failureNeeds attention

Retrofitted insulation that has slumped or absorbed water, bridging the cavity and causing damp patches on internal walls.

Typical cost: £2,000–£6,500 to extract and re-fill

Chancel repair liabilityFor information

A historic obligation to contribute to church chancel repairs, attached to some land. Rare, easily insured against, and not worth losing sleep over.

Typical cost: £20–£100 for indemnity

Cold bridgeKeep an eye on it

A path through the structure that conducts heat out faster than its surroundings — a lintel, a wall junction, an unfilled cavity. Shows up as a mould patch in exactly the same place every winter.

Completion certificateFor information

Proof that building control signed off finished work. Ask for one for every extension, loft conversion, window replacement, boiler and rewire. Buyers’ solicitors always do.

CondensationKeep an eye on it

Moisture from cooking, washing and breathing landing on cold surfaces. Shows as black spotting in corners, on ceilings and behind furniture. A ventilation problem, not a building fault.

Typical cost: £400–£2,500

Condition Rating 1For information

No repair is currently needed. The item is performing as it should. This is the good one.

Condition Rating 2Keep an eye on it

Defects that need repairing or replacing but are not serious or urgent. Most houses have a page of these. Budget for them; do not panic about them.

Condition Rating 3Needs attention

Serious defects, or defects needing urgent attention, or something that is failing and will get worse. These are the items your negotiation should be built on.

Conservation areaKeep an eye on it

Extra planning control over the character of an area. Permitted development rights are reduced, and cladding, windows and even some demolition need consent.

Consumer unitKeep an eye on it

The board with the breakers. Modern boards are metal with RCBOs; a wooden or plastic board with rewireable fuses is obsolete.

Typical cost: £700–£1,500

Damp-proof courseFor information

The barrier near the base of the wall stopping ground moisture rising. Slate, bitumen or engineering brick in older houses; plastic in modern ones.

DeflectionKeep an eye on it

A beam, joist or roof member sagging under load. Small amounts are normal in old timber; increasing amounts are not.

Typical cost: £1,500–£8,000 to strengthen

Dry rotNeeds attention

A fungus that spreads through masonry and consumes timber, in damp unventilated conditions. The genuinely serious one — it travels beyond where you can see it.

Typical cost: £3,000–£20,000

EfflorescenceKeep an eye on it

White crystalline deposit on brick or plaster where water has evaporated and left salts. A symptom of past or present moisture, not a defect in itself.

EICRFor information

A test and inspection of the fixed wiring, coded C1 to C3. It is the only meaningful evidence about the electrics — surveyors do not test them.

Typical cost: £180–£350

EWS1 formNeeds attention

External wall fire review for flats in taller blocks. Ask for it early — its absence can stall a purchase for months.

Fair wear and tearFor information

Age-appropriate condition. Not a defect. Common in reports on any house over thirty years old.

FENSA / CERTASSFor information

Self-certification schemes for replacement windows. The certificate proves the windows met building regulations. Missing ones are usually covered by indemnity.

FlashingNeeds attention

The metal weathering where a roof meets a wall, chimney or abutment. Failed flashings are the single most common cause of damp on upper floors.

Typical cost: £300–£1,500

FlaunchingKeep an eye on it

The mortar cap on top of a chimney holding the pots in. It cracks and lets water in.

Typical cost: £300–£900

Flood zoneKeep an eye on it

The Environment Agency classification of flood risk. Zone 1 is low, 3 is high. Affects insurance premiums and, increasingly, lending.

Further investigation is recommendedNeeds attention

The surveyor could not see enough to give you an answer, so they have handed you a task. Do it before exchange — an engineer, a drain camera or an EICR turns an open-ended risk into a number.

Typical cost: £180–£1,200 depending on the specialist

HeaveNeeds attention

The opposite of subsidence — the ground has swelled, often after a large tree was removed. Cracks tend to be wider at the bottom.

Typical cost: £8,000–£50,000

Hygroscopic saltsFor information

Salts left in plaster by past damp. They pull moisture from the air and set off moisture meters forever, even when the wall is dry. A frequent source of false diagnoses.

Indemnity policyFor information

Insurance that covers the financial consequence of a legal defect — missing building regs sign-off, a breached covenant — without fixing the underlying problem. Cheap, and sometimes exactly the right answer.

Typical cost: £150–£500

Japanese knotweedNeeds attention

An invasive plant lenders take seriously. Needs a professional treatment plan with an insurance-backed guarantee before most mortgages proceed.

Typical cost: £3,000–£12,000

Lath and plasterKeep an eye on it

Pre-war ceilings and walls built from timber laths and lime plaster. When it comes loose it bows and sounds hollow; overboarding is the usual fix.

Typical cost: £700–£2,500 per room

Lead supply pipeKeep an eye on it

The incoming water main is lead. Common pre-1970. Replacing the section on your side of the boundary is straightforward; the water company usually handles theirs.

Typical cost: £900–£2,500

LeaseholdKeep an eye on it

You own the property for a fixed term, not the ground under it. Check the remaining term, the ground rent, the service charge and the major works history before you fall in love with it.

LintelKeep an eye on it

The beam over a window or door carrying the wall above. Old ones can be timber, or steel that has corroded and expanded, lifting the brickwork.

Typical cost: £900–£3,500 to replace

Listed buildingNeeds attention

Legally protected. Listed building consent is needed for almost any alteration, inside and out, and doing work without it is a criminal offence.

MaceratorKeep an eye on it

A pump-and-blade unit letting a WC discharge through small-bore pipe where there is no gravity fall. Works, but some lenders and buyers dislike them on a sole WC.

Make goodFor information

Repairing the mess made by other work — filling chases, patching plaster, replacing floorboards. Almost never included in a trade’s quote, and always a real cost.

Market value subject toKeep an eye on it

The valuer has priced the house as if repairs had been done. If the repairs are not done, the house is worth less than the figure on the page.

MicroboreKeep an eye on it

Very small-diameter heating pipework, common in 1970s and 80s houses. Blocks easily with sludge and limits what a new boiler can do.

Typical cost: £1,500–£5,000 to replace

Nail sicknessNeeds attention

The nails holding slates have rusted through. Individual slates slip while the slates themselves are perfectly sound. It means a re-roof, not a repair.

Typical cost: £8,000–£25,000

Non-standard constructionNeeds attention

Anything not built of masonry cavity walls — concrete panel, steel frame, timber frame, no-fines. Some types are unmortgageable without a specific structural report.

Not inspectedKeep an eye on it

Nobody looked. Under floors, behind furniture, in a locked loft. It is not a statement that the area is fine — it is a blank space on the report.

Overhanging trees / TPOKeep an eye on it

Trees near the building affect foundations, gutters and light. A Tree Preservation Order means you need consent to touch them at all.

Typical cost: £500–£4,000

Parapet wallKeep an eye on it

A wall continuing above roof level. Exposed on three sides, so it soaks up water and is a frequent damp source in terraces.

Typical cost: £1,500–£6,000 to repair and re-cope

Part PFor information

The building regulation covering domestic electrical work. Notifiable work must be certified by a registered electrician or signed off by building control.

Party wallFor information

A wall shared with a neighbour. Cutting into it, underpinning it or building within 3m of their foundations triggers formal notice under the Party Wall etc. Act 1996.

Typical cost: £1,200–£3,500 in surveyor fees

Penetrating dampNeeds attention

Water coming in horizontally through a defect — cracked render, failed pointing, a blocked gutter, a bad flashing. Fix the defect and the damp stops.

Typical cost: £900–£5,000

PondingKeep an eye on it

Standing water on a flat roof more than 48 hours after rain. Means the falls are wrong, and it will shorten the life of any covering.

Typical cost: £2,000–£6,500 to re-lay with correct falls

PowerflushFor information

Chemically cleaning the heating system. Required by most boiler manufacturers before a new boiler goes on an old system, or the warranty is void.

Typical cost: £350–£800

PurlinKeep an eye on it

The horizontal beam supporting the middle of the rafters. Sagging purlins make a roof dip along its length.

Typical cost: £1,500–£6,000

RadonKeep an eye on it

Naturally occurring radioactive gas, significant in parts of the South West, Derbyshire, Northamptonshire and Scotland. Testing is cheap; mitigation is usually a sump and fan.

Typical cost: £50 to test, £800–£2,500 to mitigate

Regularisation certificateNeeds attention

Retrospective building control approval for work done without it. Requires opening up so the council can inspect, and any non-compliant work put right.

Typical cost: £500–£1,500 in fees, plus any remedial work

Reinstatement costFor information

What it would cost to rebuild the property from scratch, for buildings insurance. It is deliberately unrelated to market value and is usually lower.

RepointingKeep an eye on it

Raking out and renewing the mortar joints. On any pre-1919 solid wall it must be lime mortar — cement pointing traps water in the brick and causes spalling.

Typical cost: £1,800–£7,000 per elevation

Restrictive covenantKeep an eye on it

A binding restriction in the title on what you may do with the property — no extensions, no business use, no caravans. Some are ancient and unenforceable; some are not.

RetentionNeeds attention

Your lender is holding back part of the loan until specified works are done. You still have to complete — and you have to fund the works before you get the money.

Rising dampNeeds attention

Groundwater drawn up through masonry where there is no working damp-proof course. Genuinely uncommon, and diagnosed far more often than it occurs. Usually tops out around a metre.

Typical cost: £2,000–£8,000 including replastering

Section 20 noticeNeeds attention

A leaseholder’s formal warning that major works are coming and you will be billed a share. Ask whether one has been served — you inherit the bill.

Serviceable lifeKeep an eye on it

How long the surveyor expects the item to keep working. "Nearing the end of its serviceable life" is a forecast, not a leak.

SettlementFor information

Normal downward movement as a building beds into the ground in its first few years, or after an extension. Not subsidence. Usually stops on its own.

Short leaseNeeds attention

Under about 80 years, extending becomes markedly more expensive because marriage value kicks in. Under 70, many lenders will not lend at all.

Typical cost: £10,000–£60,000+ to extend

SnaggingFor information

The list of defects in a new build. Worth paying an independent inspector for before you complete — developers fix what is on a list far more readily than what is in an email.

Typical cost: £300–£600

Solid wallFor information

No cavity. Standard in pre-1919 housing. It breathes, so it needs lime mortar and breathable paint — cement render and plastic paint cause damp.

SpallingKeep an eye on it

The face of the brick has blown off, usually from frost or from being pointed in cement that trapped moisture. Cosmetic at first, structural if it spreads.

Typical cost: £40–£90 per brick to cut out and replace

Spray foam insulationNeeds attention

Foam sprayed to the underside of the roof. Several mortgage lenders will not lend on a property that has it because it hides timber decay and blocks ventilation.

Typical cost: £2,500–£8,000 to remove

Structural movementNeeds attention

The building has moved. The question is when, why, and whether it is still moving. Historic movement that stopped decades ago is extremely common and usually harmless.

Typical cost: £500–£1,200 for an engineer’s report before anything else

Sub-floor ventilationNeeds attention

Airbricks keeping the void under a suspended timber floor dry. Blocked or built over, the joists rot. Clearing them is cheap and prevents a five-figure problem.

Typical cost: £300–£1,200

SubsidenceNeeds attention

The ground beneath the foundations has sunk, usually from clay shrinkage, tree roots or a leaking drain. Cracks are typically diagonal, wider at the top, and often near openings.

Typical cost: £5,000–£45,000 depending on cause; often far less than feared

TankingFor information

A waterproof membrane applied to walls or floors — in basements, and behind tiles in bathrooms. Tiles and grout are not waterproof; the membrane is.

Typical cost: £400–£1,100 in a bathroom

Thermal movementFor information

Materials expanding and contracting with temperature. Produces fine, often vertical cracking near junctions of different materials. Cosmetic.

Typical cost: £150–£600 to fill and decorate

TorchingFor information

Old lime mortar applied to the underside of slates before felt existed. Crumbling torching in a loft is normal in a Victorian roof, not an emergency.

Trickle ventFor information

The small slot vent in a window frame. Required in most new windows, and the cheapest defence against condensation in the house.

Underfelt / sarking feltKeep an eye on it

The membrane beneath the tiles that catches wind-driven rain. It perishes at 25–40 years and cannot be replaced without stripping the roof.

Typical cost: £8,000–£18,000 as part of a re-cover

UnderpinningNeeds attention

Deepening or strengthening foundations. The last resort, not the first, and needed far less often than homeowners fear.

Typical cost: £15,000–£50,000

Unvented cylinderFor information

A pressurised hot water cylinder. Needs an annual check of the expansion vessel and safety valves, and a G3-qualified installer.

Typical cost: £120–£180 a year to service

ValleyNeeds attention

The internal angle where two roof slopes meet, usually lined in lead. When it fails, water goes straight into the middle of the house.

Typical cost: £700–£3,000

Verge and ridgeKeep an eye on it

The edges and apex of a roof. Traditionally bedded in mortar, which cracks and needs redoing; dry-fix systems are mechanical and maintenance-free.

Typical cost: £600–£2,200

Wall plateNeeds attention

The timber sitting on top of the wall that the rafters land on. Rots where gutters have overflowed for years. Awkward and expensive to replace.

Typical cost: £2,000–£8,000

Wall tie failureNeeds attention

The metal ties joining the two leaves of a cavity wall have rusted and expanded, producing regular horizontal cracking every few courses.

Typical cost: £2,500–£9,000

Wet rotKeep an eye on it

Timber decaying where it stays wet. Stops when the water stops. Far more common and far less serious than dry rot.

Typical cost: £700–£4,500

WoodwormKeep an eye on it

Beetle larvae in timber. Clean, sharp holes with pale dust mean it is active; grey, dusty old holes mean it burnt out decades ago. Most reported woodworm is historic.

Typical cost: £600–£4,000 if active