The valuation of development land starts from what the land can become rather than from what it is, which is why the planning appraisal comes first: the developer reads the envelope, the class Q route, the constraints and the policy on the plot, decides the scheme the site will support, and only then values the land. How do you value land is then the residual method: the gross development value of the finished scheme, less the costs of building it, the professional fees, the finance, the section 278 works, the levy, the net gain, the abnormals, less the developer's return for the risk, leaves the residual land value, the most the developer can pay. Land valuation UK practice adds a second reading, benchmark land value, the existing use value of the land plus a premium that gives the owner a reason to sell, and a residual below the benchmark is a scheme that does not work; residential development land values per acre published by valuers are comparisons, not the answer, because the per-acre figure hides the density and the policy that produced it. This page sets out land appraisals as the developer makes them before the offer.
The planning appraisal, and why it precedes the valuation
A plot is worth what it may become, so the developer reads the permitted envelope, the class Q or class R route, the designation, the article 4 direction, the tree preservation order, the green belt or grey belt position and the net gain exposure before any figure is written down; the sheets on this site read the two routes that are arithmetic, and the guides read the rest. The scheme that survives the reading is the one the gross development value is built on, and a valuation made on the agent's scheme rather than the reading is the usual overpayment.
The residual: gross development value, costs, return, land
The gross development value is the sale value of the finished units, from comparable sales of the finished product rather than of the land; the costs are construction, contingency, professional fees, finance, the levy, the section 278 works, the net gain units, the abnormals and the sales costs; the return is the margin the developer needs for the risk; and the residual is what is left for the land. Every line is an estimate, so the land value is a range, and a small change in the gross development value moves the residual by a large share of itself, which is the reason land values swing further than house prices.
Benchmark land value, per-acre comparisons and what the file keeps
National guidance on viability reads land value as existing use value plus a premium for the owner, the benchmark, and a scheme whose residual falls below it will not buy the land; a residual far above it is the developer's margin to negotiate, not the price to offer. Per-acre land values published by valuers are a sanity check by region and use, and nothing more, because they carry the density and the policy of the sites that made them. Curtilo Pro keeps the planning appraisal, the gross development value, the cost lines and the residual against the plot with the date and the comparables, so the offer is a record; the guidance cited below sets out the method.
Questions people ask about valuation of development land
How is development land valued?
By the residual method: the gross development value of the scheme the site will support, less the costs of building it and the developer's return, leaves the land value. The planning appraisal that decides the scheme comes first.
What is benchmark land value?
The existing use value of the land plus a premium that gives a willing owner a reason to sell, as national viability guidance reads it. A residual below it is a scheme that does not buy the land.
Are land values per acre a reliable guide?
Only as a comparison by region and use. The per-acre figure hides the density, the policy and the abnormals of the sites that produced it, and the residual on the plot in hand is the reading.
Sources
- GOV.UK planning practice guidance, Viability: the residual method, benchmark land value, existing use value plus a premium and the developer's return
- GOV.UK, National Planning Policy Framework: the grey belt definition, the golden rules and the presumption in favour of sustainable development
- GOV.UK planning practice guidance, When is permission required: development, permitted development rights, prior approval and article 4 directions