Secondary Suite & Basement Suite Valuation in London
How London appraisers value secondary suites, basement apartments, and legal vs. non-conforming rental units.
Secondary suite value in London hinges on one question
Secondary suite value in London hinges on one question: is the suite legal, legal non-conforming, or unpermitted? A legal, self-contained suite with permits is credited at market rent; an unpermitted suite is typically treated as bonus space only.
Documentation that moves the value
Documentation that moves the value: municipal permits, occupancy certificate, fire-code compliance evidence, and separate entrance / utility metering. Send these when ordering.
London-specific considerations
London-specific considerations: Duplex / secondary-suite conversions common; legal-vs-illegal use is the critical scope question.
Income approach overlay
Income approach overlay: where the suite is legal and rented, the appraiser may include a supporting income analysis using local market rent. This does not usually replace the sales-comparison conclusion for a single-family property but supports it.
Turnaround for a suite-inclusive report in London runs 4
Turnaround for a suite-inclusive report in London runs 4–8 business days; add 1–2 days if permit records need to be pulled by the appraiser.
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