A landlord holds a commercial EPC for an entire building. A tenant now wants the ground-floor unit, or a managing agent is marketing three floors separately. Is the existing certificate enough? The answer depends on how the premises are divided, what space is being sold or let and how the units are conditioned. The building boundary matters as much as the address on the certificate.
Start with the actual premises being marketed
Mark the demise on a current floor plan: which rooms, floors and entrances belong to the transaction? Note whether a common corridor, reception or plant room serves more than one occupier. A certificate for the whole property should not be assumed to cover every newly defined unit without checking the rules and assessment scope. Government guidance allows different approaches for individual parts and whole buildings in particular configurations; an accredited non-domestic assessor should decide the correct route.
Shared plant can change the assessment boundary
A subdivided office with one central heating system presents a different question from shops with independent heating and controls. Conditioned communal space may also need to be considered separately. The result is not decided by a postcode or the number of leases alone. Give the assessor a simple schedule showing each unit's use, floor area, heating, cooling, ventilation, lighting and any shared services. For mixed-use premises, identify residential areas rather than assuming one commercial assessment covers them.
Check the register before commissioning more work
Search for existing Energy Performance Certificates by address and inspect the certificate's description and date. A valid non-domestic EPC may already be available for the exact building or part you need. If the layout or fixed services have changed since assessment, explain the changes to the assessor. Keep plans and plant specifications together: incomplete information can force permitted defaults and obscure the building's actual specification. London retail and office portfolios benefit from one unit-by-unit register of certificate references and expiry dates.
Make the answer usable for the deal
Before marketing or negotiating a lease, agree the intended unit boundary with the owner, agent and assessor. Ask which certificate is relevant and whether a separate assessment is required; seek legal advice on transaction obligations or minimum energy efficiency rules. This short scoping step can prevent an apparently convenient whole-building EPC from being presented for the wrong premises. Our Commercial EPC service can review the plans and advise on the assessment information needed.