Affordable housing in an English development appraisal

A British urban street combining older brick industrial buildings and contemporary infill. — Existing fabric and local context shape the development appraisal.

What to take into your next appraisal

Separate tenure, size and transfer price.
Use the project policy and agreement, not a national percentage.
Test transfer timing alongside the number of affordable homes.

Translate the local requirement into units

Start with the development plan, permission and negotiated agreement. Confirm whether the requirement is expressed by units, floorspace or another measure, and identify tenure, eligibility and delivery restrictions. English viability guidance expects policy requirements to be reflected in land-price expectations.

An affordable-housing percentage does not supply a transfer value. Obtain a provider offer or a supported valuation with specifications, payment stages and conditions. Do not infer a discount from the label alone.

Sources: Ministry of Housing, Communities and Local Government: Viability; Ministry of Housing, Communities and Local Government: Planning obligations

Reconcile one fictional 100-home scheme

Assume 70 market homes sell for £400,000 each and 30 affordable homes transfer for £180,000 each. Gross receipts are £28m plus £5.4m, or £33.4m. Assume total development cost of £28m, including land and financing, with no additional grant.

Fictional equal-size homes; cost held fixed to isolate revenue mix. No claim about local policy or current values.
Case	Market receipts	Affordable receipts	Total receipts	Surplus
30 affordable homes	£28m	£5.4m	£33.4m	£5.4m
40 affordable homes	£24m	£7.2m	£31.2m	£3.2m

Rebuild costs when tenure changes

The £2.2m revenue reduction in the second case follows ten homes switching from £400,000 to £180,000. In a live model, costs rarely stay exactly fixed: specifications, common areas, parking, management arrangements and sales costs can differ.

Allocate shared infrastructure using a disclosed basis. An arbitrary equal share may distort a small tenure block with disproportionate access or servicing costs. Reconcile allocated costs to the scheme total.

Tie the provider payment schedule to funding

Suppose the base £5.4m transfer receipt moves from month 18 to month 24 while costs and market sales stay unchanged. The project needs an additional £5.4m through that six-month interval unless another funding source fills it. At an illustrative 8% simple bridge rate, the incremental interest is £216,000.

Do not assume a forward sale produces unrestricted cash on signature. Record the contractual conditions, certification and security needed for each payment.

Present policy and commercial sensitivities separately

Report the agreed base, an alternative tenure mix and a delayed-transfer case. Show gross receipts, total costs, peak equity and the land value each case can support.

A sensitivity is not permission to disregard a policy obligation. Any proposed change needs planning and legal support, while the model should keep the current requirement visible until it is formally replaced.