A reinstatement cost assessment (RCA) answers one specific question: if this building burned to the ground tomorrow, what would it cost to clear the site and rebuild it, to its original specification, today? That's it — nothing about what it would sell for. For an ordinary modern house with a site visit, expect somewhere around £300–£900+VAT, rising to £750+VAT or more for listed buildings, and £1,000–£3,000+ for commercial property. Cheaper "desktop" figures exist too, but they come with a real catch, covered below.
Most people never commission one at all. They take whatever number their insurer suggests at renewal, or lean on a free online calculator, and move on. That's fine for a standard three-bed semi that hasn't been touched since it was built. It's a genuinely bad idea for a listed cottage, a timber-framed barn conversion, a house that's doubled in size since the policy started, or anything else that doesn't look like the model house a generic calculator was built around.
The professional fee below buys a report, not just a number — a "declared value" a surveyor is prepared to stand behind, built on published construction-cost data rather than a guess.
The short answer
Figures below are cross-checked across several UK surveying-practice cost pages against Which?'s own reporting on rebuild-cost assessment, current to September 2026. Treat the standard-house range as the reliable core figure; anything above £1,000 is realistic for larger, more complex or commercial properties rather than typical.
| Property type | Typical cost (2026) | What's included |
|---|---|---|
| Standard house or flat, with site visit | £300–£900+VAT | Inspection, floor area measurement, BCIS-referenced cost model, written report |
| Listed or non-standard construction | from £750+VAT | Manual assessment outside the standard model; specialist materials and trades priced individually |
| Commercial property | £1,000–£3,000+ | Scales with floor area and building complexity |
| Desktop assessment, no site visit | £100–£500 | Cheaper, but explicitly outside the RICS professional standard — some insurers won't accept it as the basis for cover |
Worth separating from the fee itself: the rebuild figure it produces. National rebuild costs for standard construction run around £2,200–£2,800 per m² (higher again in London), while listed or heritage buildings can run £3,000–£13,000 per m² depending on the materials and trades involved — lime render, stone, oak framing and hand-made bricks all cost far more to replicate than a modern equivalent.
What drives the price
Floor area, measured, not guessed. The standard model is driven by gross internal floor area, so an assessor measures the building rather than relying on the figure from your last mortgage valuation or the estate agent's listing, which are often rounded or simply wrong.
Construction type. RICS's own professional standard on this points members toward BCIS's Rebuild Online service — a standard cost-per-m² model — for typical houses and flats, and to a slower manual assessment for anything outside its scope: larger floor areas, higher specification finishes, mixed-use buildings, or listed and traditionally-built stock. That manual route costs more because it takes more of a surveyor's time, not because of any different accreditation.
Site visit vs desktop. A proper assessment involves walking the building, not just looking up a postcode. Desktop-only figures are cheaper for exactly that reason, and it shows in what they're worth: RICS's standard states plainly that assessments without a site visit fall outside its scope, and some insurers won't rely on one when a claim's on the table.
Bundling with a survey. Several firms price an RCA down when it's added to a full building survey visit, since the surveyor is measuring and inspecting the property anyway. Worth asking about if you're already commissioning one.
Reinstatement cost vs market value — the distinction that actually matters
These two figures can point in opposite directions, and mixing them up is the single most common mistake homeowners make. A large detached house on a valuable plot in the South East might be worth £800,000 to sell, with land accounting for half or more of that price — but its rebuild cost, the bricks-mortar-and-labour figure, might be only £350,000–£400,000, because you don't rebuild the land. Insure it for the sale price and you're needlessly paying premium on cover you'll never claim.
Run it the other way for a listed cottage or a traditionally-built house in a less expensive part of the country, and the rebuild cost can genuinely exceed the market value. Reinstating a listed building "like for like" — matching the original stone, timber, lime mortar and joinery, often under conservation officer supervision — costs far more per square metre than building new, and in a lower-value area that premium can push the true rebuild figure above what the house would fetch on the open market. Under-insure that property using a market-value instinct and you're exposed to a real shortfall on the one policy that's supposed to cover exactly this.
Why most people are underinsured without realising it
Which?'s own research found that only around 5% of homeowners have ever had their rebuild cost professionally assessed; roughly 43% simply take the figure their insurer suggests, which can be a generic default rather than anything specific to the property, and most people never revisit the number once a policy is set up. Separately, the ABI/BCIS House Rebuilding Cost Index — the industry benchmark, published directly by BCIS — rose almost 5% in the year to January 2026, on top of nearly 4% the year before. A figure that was accurate five years ago is very likely stale now, even on a house that hasn't changed at all.
The consequence isn't abstract. Most UK buildings insurers apply a "condition of average" clause: if your declared rebuild figure is below the true cost, they can reduce any claim payout proportionally, not just on a total loss. The Financial Ombudsman Service's own guidance gives the example plainly — insure for half the true rebuild cost and a valid claim can be settled at half its value, whether that's storm damage to a roof or a full fire loss. Industry data on the size of the problem varies by source, but the direction is consistent: a meaningful majority of UK homes carry rebuild cover below their true reinstatement figure, and a smaller but rising share are now over-insured the other way — paying premium on cover they don't need.
RICS's own standard recommends reviewing the figure every three years, or sooner after any extension, loft conversion or major renovation — changes that move the rebuild cost even when they barely move the sale price.
Who actually does this work
Here's where I'll be straight about my own position. A reinstatement cost assessment isn't a Red Book valuation and, on RICS's own reading of its standard, isn't formally gated to RICS Registered Valuer status — it's a construction-cost skill, closer to quantity surveying than to market valuation. But market practice has settled around it being carried out by RICS-regulated firms with a BCIS subscription, since BCIS's Rebuild Online tool is the industry-standard cost model insurers and brokers recognise, and access to it is sold primarily to RICS members' practices.
I'm an RPSA member and ACABE Associate, not RICS, and I don't hold a BCIS subscription — so I won't offer you a formal, BCIS-referenced reinstatement cost assessment as a standalone product, and I'd rather say that plainly than stretch what I do into something it isn't. Where this genuinely does come up in my own work is during a building survey: if a property's insured rebuild figure looks obviously stale, or the house has been substantially extended since it was last reviewed, or it's a listed property (see listed building consent cost for the related paperwork side) where the "just use a national average" instinct is likely to be wrong, I'll flag it as a line in the report — not as a substitute for a proper assessment, but as the nudge that gets a client to commission one before renewal rather than after a claim goes wrong.
What I'd watch for in a quote
- Whether it includes a site visit. A desktop-only figure is cheaper and, per RICS's own standard, explicitly outside the professional scope — fine as a sanity check, not as the number you rely on for cover.
- Whether the assessor references BCIS or an equivalent published cost dataset, rather than a flat "experience-based" figure with no stated methodology behind it.
- Whether the quote flags non-standard construction at all. A generic online calculator built around brick-and-block houses has no reasonable basis for pricing a thatched roof, a timber frame or a listed building — if the tool doesn't ask, it can't know.
- A stated date for the figure, and a suggested review point. A rebuild cost with no date attached is already on its way to being wrong, given how fast build costs have been moving.
- Professional indemnity insurance in place, the same basic check worth making of anyone producing a figure your insurer will rely on.
Questions I get asked
What's the difference between a reinstatement cost assessment and a valuation? An RCA is a construction-cost exercise, not a market valuation — it estimates what it would cost to clear the site and rebuild to the original specification, for insurance purposes. RICS's own standard is explicit that it isn't a Red Book valuation. A mortgage, probate or sale valuation asks what the property would sell for, which can be a completely different figure, and neither one substitutes for the other.
How often should I get one done? RICS's own guidance suggests every three years, or sooner after a significant alteration. Build-cost inflation alone moved the industry benchmark index by close to 5% in the year to January 2026, so even an untouched house is worth revisiting if the figure's several years old.
What actually happens if I'm underinsured? Most UK insurers apply a "condition of average" clause, reducing any claim payout proportionally if your sum insured is below the true rebuild cost — not just on a total loss. The Financial Ombudsman Service gives the example of insuring for half the true figure and having an otherwise valid claim cut in half as a result.
Can I just use my insurer's own rebuild cost calculator? For an ordinary, modern, unaltered house it's a reasonable starting point. But it's explicitly outside RICS's professional standard without a site visit, and it isn't built to handle listed, timber-framed, heavily extended or otherwise non-standard properties — don't trust it for any of those.
If a building survey turns up a rebuild figure that looks stale, or a listed or traditionally-built property where a generic insurer calculator was never going to give you the right answer, that's exactly the kind of thing I'll flag in plain English rather than let pass. Call 07946 618203 or get in touch and I'll give you a straight read on whether your buildings cover looks right before it's tested by a claim.
Small print. This guide is general information, not advice on a specific property or policy, and it doesn’t replace speaking to your own insurer, broker or a suitably qualified surveyor. Prices were researched and correct to the best of my knowledge on 26 September 2026; costs move and vary by region, property and provider. Always get at least three written quotes, and check your buildings insurance sum insured directly with your insurer or broker.