Vacant Building Credit and how the offset is calculated

Vacant Building Credit reduces an affordable housing requirement in proportion to the vacant floorspace you are reusing or replacing. The arithmetic is simple: the existing gross floorspace of the qualifying vacant building is set against the proposed gross floorspace, and the affordable housing contribution is calculated only on the net increase. The argument is never about the arithmetic. It is about whether the building qualifies, whether it was vacant or abandoned, and whether the local plan has disapplied the credit.

Get the evidence together before you submit, because a claim made in a covering letter and evidenced after refusal rarely recovers.

What the credit does to an affordable housing requirement

National policy says that where a vacant building is brought back into any lawful use, or is demolished and replaced, the developer should be offered a financial credit equivalent to the existing gross floorspace of relevant vacant buildings when the authority calculates the affordable housing contribution. The credit applies to the contribution, not to the policy requirement itself.

Take the current edition of the Framework from gov.uk and check the policy code before quoting it in a statement, because the August 2026 edition replaced numbered paragraphs with policy codes and older copies are still in circulation.

The effect is proportionate rather than absolute. A scheme replacing a large vacant building with a modest uplift in floorspace may end up with a very small affordable requirement. A scheme replacing a small vacant building with a large one sees little benefit.

Buildings that qualify and those that do not

Four questions decide qualification, and councils test all four.

• Is there a building, as opposed to hardstanding, a foundation slab or a structure that has effectively ceased to exist? Cleared sites do not attract the credit.
• Is it vacant at the relevant date, and has it been vacant for a meaningful period rather than for the weeks between exchange and application?
• Has it been abandoned, which is a different question from vacancy and defeats the claim?
• Is it a building the local plan excludes, such as one that has been in an affordable housing use, or one covered by a policy that disapplies the credit?

Buildings vacated deliberately to attract the credit are the obvious target of scrutiny. National guidance expects authorities to consider whether the building has been made vacant for the sole purpose of redevelopment, and a tenant served notice shortly before an application invites that finding.

Abandonment and the vacancy test

Vacancy is a fact about occupation. Abandonment is a legal conclusion about the lawful use, and once a use is abandoned it cannot be resumed without permission, which also removes the basis for the credit.

The courts have approached abandonment through four factors: the physical condition of the building, the length of the period of non-use, whether there has been any intervening use, and the owner's intentions. A roofless former workshop with trees growing inside, empty for fifteen years, is a strong candidate for abandonment. A unit empty for 18 months, weathertight, rated and actively marketed, is not.

This is the point at which claims are won or lost, so build the record deliberately:

1. Business rates records showing the rating history, including any empty property relief.
2. Marketing evidence, with the agent's particulars, the asking terms, the duration and a schedule of enquiries and viewings.
3. Utility accounts and meter readings showing the pattern of use.
4. Dated photographs inside and out, showing the building is weathertight and secure.
5. The lease or tenancy history, including the reason the last occupier left.
6. A structural note where condition is in dispute, which may sit alongside a structural survey if conversion is proposed.

Calculating the floorspace offset

Measure consistently and say how you measured. Gross internal area and gross external area give different answers, and a claim that measures the existing building one way and the proposal another will be rejected.

Illustrative example. A vacant former office of 1,400m² gross internal area is replaced by a scheme of 2,600m² gross internal area containing 28 flats. The credit covers 1,400m², so the affordable housing contribution is calculated on the net increase of 1,200m², which is about 46 per cent of the proposed floorspace. Where the policy requirement is 30 per cent affordable housing by habitable rooms or units, the contribution is scaled to that proportion, giving roughly 14 per cent of the scheme as affordable rather than 30 per cent. The figures are illustrative and the mechanics of applying the proportion vary between local plans.

Two mechanical points cause arguments. Where the policy requirement is expressed in units or habitable rooms and the credit is expressed in floorspace, the conversion has to be set out explicitly. And where the scheme is phased, the credit should be applied across the whole development rather than consumed entirely by the first phase, which is a point our note on phasing a large scheme without gaming thresholds touches on.

Where councils resist the credit

Resistance takes three forms, and only one of them is a real answer to a well evidenced claim.

The first is a local plan policy that disapplies or limits the credit. Where a plan has been examined and adopted with such a policy, section 38(6) of the Planning and Compulsory Purchase Act 2004 means the development plan is the starting point, and the credit becomes a material consideration to be weighed rather than an entitlement. Check the adopted policy wording first, because this changes the whole approach.

The second is a factual challenge on vacancy or abandonment. That is answered with the evidence list above.

The third is an argument that the credit should be traded against something else, such as a higher tenure mix on the remaining affordable units or a larger contribution elsewhere. That is negotiation rather than policy, and it is worth engaging with where the alternative is refusal.

Presenting the claim in the statement

Put the claim in the Affordable Housing Statement rather than in a letter, with a floorspace schedule, the basis of measurement, the vacancy evidence as appendices and the resulting contribution calculated in full.

Where the credit is contested and the scheme is marginal anyway, run it alongside a Viability Assessment so the fallback position is evidenced. A refusal that defeats the credit on abandonment grounds does not help you if the viability case was never made.

Keep the planning case consistent. If the Planning Statement describes a building in such poor condition that demolition is the only option, the same condition evidence can be used against you on abandonment. State the position once, accurately, and deal with the tension directly rather than hoping the officer reads only one document.

This is general guidance, not legal advice; check the position with your local planning authority or a qualified professional before relying on it. PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval.