Energy hierarchy for a commercial fit-out after change of use

An energy statement for a commercial fit-out after a change of use can only commit to what the applicant actually controls, and that is the sentence most of these documents are missing. If the landlord is delivering shell and core and the incoming occupier is fitting out, the planning application sits across two scopes of work with two budgets and two completion dates. Work out which party owns which measure before writing a word of the assessment, or the condition you receive will bind somebody who never agreed to it.

The energy hierarchy still structures the answer. Reduce demand, then supply efficiently, then add low-carbon generation, then report what the building actually uses.

Who is responsible for which part of the assessment

Three contracting patterns turn up, and each produces a different statement.

In a landlord-led change of use, the landlord applies, delivers the fabric and primary plant, and lets a fitted unit. The energy statement can commit across the whole scope, and the conditions are enforceable against the applicant who will carry them out.

In an occupier-led change of use, the tenant applies, often under an agreement for lease, and controls only the fit-out. Fabric and primary plant are outside the application's reach. The statement has to say so, and should set out what the occupier will do and what already exists.

In the split case, the landlord delivers shell and core and the occupier fits out. This is where statements go wrong, because the applicant signs up to a whole-building performance figure that depends on works another party will carry out, sometimes two years later.

Name the parties and the scopes in the statement. A table with three columns, the measure, the party delivering it and the stage at which it is delivered, answers most of the officer's questions before they are asked.

Shell and core against fitted out performance

Building Regulations treat these stages differently from planning. A material change of use brings specified elements within Part L, and the fit-out itself is building work that has to comply on its own terms. The compliance calculation for a shell and core handover is made on notional fit-out assumptions, and the as-built figure can diverge from it considerably.

Planning policy generally asks for a percentage improvement against a baseline, or an absolute carbon figure, or both. Read the adopted policy carefully to see which stage it bites at. A policy written for new build sometimes makes little sense applied to a change of use in an existing envelope, and saying that plainly in the Energy Statement is better than producing a number that cannot be delivered.

Where the building is in London, the energy hierarchy and the monitoring expectations in the London Plan apply, and the reporting stage extends beyond practical completion.

What a change of use application can realistically commit to

Be honest about the envelope. A 1980s retail unit becoming a gym has single glazed shopfronts, an uninsulated flat roof and a concrete slab with no insulation beneath it. The fabric measures available are roof insulation where access allows, shopfront replacement, draught sealing and insulated linings where the loss of floor area is acceptable.

Those are usually worth doing, and the carbon saving from them is modest against the saving available from the services. Say both things.

What a change of use can commit to with confidence:

• Replacement of heating and cooling plant with heat pumps, where plant space, electrical capacity and acoustic constraints allow.
• Full LED lighting with daylight dimming and presence detection.
• Mechanical ventilation with heat recovery, with specific fan power stated.
• Hot water strategy matched to the use, which for a gym or a food use is a much larger load than for an office.
• Controls, zoning and a building management system scaled to the building.
• Sub-metering by end use and by tenancy.

What it usually cannot commit to: a deep fabric retrofit that the lease does not fund, a solar array where the roof is in the landlord's demise and outside the application, or a connection to a heat network that does not yet exist. Where a network is planned, safeguarding plant space and a connection point is the deliverable, and safeguarding a future heat network connection sets out how to describe that.

Services, lighting and controls as the main levers

For most commercial fit-outs, the services carry the carbon reduction.

Lighting is the quickest win. Replacing an old fluorescent installation with LED luminaires at a stated luminaire efficacy, zoned and controlled by daylight and occupancy, produces a reduction that is easy to evidence and hard to argue with.

Heating and cooling come next. Air source heat pumps are the default low-carbon answer, and the planning questions they raise are external unit position, acoustic performance at the nearest noise sensitive facade, and refrigerant choice. That last point now appears in local policy in some authorities, and the reasoning in refrigerant choice and global warming potential sets out the position before you specify a unit.

Ventilation is where fit-outs quietly lose efficiency. A heat recovery unit sized for the wrong occupancy, or ducted so badly that fan power doubles, undoes the gain from better plant. State the design occupancy, the air change rate and the specific fan power.

Where a BREEAM assessment is required by policy, a BREEAM Pre-Assessment at application stage sets the credit strategy. Councils normally expect a licensed assessor to carry out that work, and professional review is strongly advised.

Metering and the landlord and tenant split

Metering is the mechanism that makes everything else verifiable, and it costs little at fit-out and a great deal afterwards.

Specify sub-meters by end use, so heating, cooling, ventilation, lighting, small power and any process load are separately recorded. Specify them by tenancy as well where the building is multi-let. Connect them to automatic meter reading so the data exists without someone walking round with a clipboard.

Then decide who reads them. A landlord who holds the data can report building performance and answer a monitoring condition. A tenant who holds it can manage consumption and renegotiate a service charge. Both parties usually want the same information for different reasons, and the lease should say who provides it to whom.

Set the metering strategy out in the application. An officer asked to accept a performance commitment will take it more seriously where the means of measuring it is drawn on the plans.

Conditions that bind a future occupier

Here is the practical problem. A condition requiring a fit-out to achieve a stated standard is enforceable against the person carrying out the development, and where that person is a landlord building shell and core, the condition cannot sensibly be discharged at their completion.

Three drafting approaches work better.

1. Split the condition by stage: fabric and primary plant before practical completion of the shell, fit-out measures before first occupation of each unit.
2. Tie the trigger to occupation rather than to completion, so each incoming occupier's works are caught at the right moment.
3. Where a performance outcome is wanted, require submission of the as-built calculation and the energy performance certificate before first occupation, rather than requiring a number that cannot be tested until the building is in use.

Conditions have to be precise and enforceable to be lawful, and a condition requiring an unidentified future tenant to do something is neither. Say so at the application stage and offer the alternative wording. Officers generally accept it, because an unenforceable condition helps nobody.

A Sustainability Statement is often the right home for the wider commitments, with the energy calculations kept separate.

Evidence at completion and who provides it

Agree the completion evidence package when the condition is drafted, not when it falls due.

• The as-built compliance calculation output for the relevant part of the works.
• The energy performance certificate, with the assessor's name and accreditation.
• Commissioning records for heating, cooling, ventilation and lighting controls.
• Photographic evidence of installed insulation and plant, dated.
• The metering schedule as installed, with meter serial numbers.
• Where a monitoring obligation applies, the first reporting submission and the format agreed with the authority.

Allocate each item to a party in the lease or the agreement for lease. The commonest failure is a landlord who cannot discharge a condition because the tenant holds the commissioning records and has no contractual reason to hand them over.

This is general guidance, not legal advice. Check the position with your local planning authority or a qualified professional before relying on it, and confirm the policy requirements against the adopted development plan.

For specialist technical reports, qualified professional input may be required. See PlanScope pricing if you want to draft the energy and sustainability documents yourself and send them for professional review. PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval.