The Future Homes Standard and the Part L uplift

The Part L uplift that came into force on 15 June 2022 was an interim step, not the destination. It raised the carbon target for new dwellings by roughly 31 per cent against the previous standard and brought in Part O for overheating, Part S for electric vehicle charging and a revised Part F for ventilation. The Future Homes Standard is the step after it, and it has been developed through consultation with the intention that new homes produce substantially lower emissions and need no retrofit work to be zero-carbon ready.

As at the date of writing, architects should verify the current status of the Future Homes Standard, the applicable Approved Documents and any transitional arrangements on gov.uk before fixing a specification. Standards in this area have moved repeatedly, and a scheme designed to a superseded document is a scheme that gets redesigned.

What the 2021 uplift actually changed

Four things, and they interact.

The dwelling emission rate target tightened, which in practice pushed schemes towards better fabric, lower-carbon heat and often photovoltaics. Notional building specifications changed with it, so the target moved as well as the calculation.

Part O introduced a requirement to limit overheating in new residential buildings, with a simplified method and a dynamic thermal modelling route. It applies to new dwellings including those created by material change of use.

Part S introduced electric vehicle charge point requirements for new dwellings and for larger non-residential buildings. Charge point positions, cable routes and any external equipment need space allocated on the layout, and on a scheme with parking courts the electrical capacity question arrives with them, which is a conversation with the distribution network operator rather than with the council.

Part F was revised alongside, which matters because a tighter envelope needs a ventilation strategy that works rather than one that is assumed.

Transitional arrangements applied where the relevant notice was given before 15 June 2022 and work on the individual building started within a year. Those have long since run out for new schemes, but they still explain why buildings completed at different times on the same site can be built to different standards.

Where the planning system fits

This is the part architects underestimate. The Building Regulations set the performance standard, but several of the measures needed to meet it are planning matters, and they have to appear on the planning drawings.

Air source heat pumps have external units. Their position, acoustic treatment and appearance are planning questions, and permitted development for domestic units under the General Permitted Development Order carries conditions that have been amended more than once. Check the current text of Part 14 rather than working from memory, because both the volume limit and the boundary restriction have changed.

Photovoltaic arrays change roofscapes, which matters in conservation areas and on prominent elevations.

Part O mitigation frequently means external shading, smaller or differently proportioned windows, or a change in orientation. All of those are visible on elevations. Discovering the requirement after planning consent means either a fresh application or a scheme that cannot comply.

Ventilation plant, flues, terminals and intake positions belong on the drawings for the same reason.

An Energy Statement that describes the strategy without showing where the equipment goes is only half a document.

One more planning consequence, often overlooked. Where a scheme relies on a communal heat network or a shared plant room, that plant needs a home on the drawings with access for maintenance and replacement, and an energy centre in a residential block has acoustic and servicing implications of its own. Councils have refused schemes where the energy strategy described a system the drawings had no room for.

Overheating is the practical constraint

Of everything the uplift introduced, Part O causes the most redesign, particularly on urban sites.

The conflict is straightforward. Overheating mitigation usually relies on openable windows and cross-ventilation. Noise from a road or a neighbouring commercial use argues for windows that stay shut. Security and fall protection restrict opening area. Single-aspect flats have no cross-ventilation at all.

Run an Overheating Risk Assessment at the same time as the massing study, not after it. The CIBSE TM59 methodology and the dynamic modelling route in the Approved Document both need the geometry, and both will tell you whether the scheme works before the drawings are frozen.

Where the assessment concludes that mechanical cooling is needed, that has consequences for the energy strategy and sometimes for the planning case, since plant space and external condensers reappear.

Two further points on sequencing. Acoustic and overheating consultants should be working from the same window schedule, because an acoustic report that assumes closed windows and an overheating report that assumes open ones cannot both be right. And where the site sits on a busy road, resolve that conflict before the elevations are drawn rather than after the officer spots it.

Local plan energy policies

Councils have long set their own energy standards in local plans, using powers that allow requirements beyond the Building Regulations. Government has more than once told authorities to be cautious about doing so, and the current expectation is that local standards should be justified, costed and expressed in a way that is compatible with national standards rather than cutting across them.

The practical position for an applicant is that both apply. The local plan policy governs the planning decision. The Building Regulations govern what gets built. Where the two use different baselines, the Sustainability Statement has to show compliance with each on its own terms rather than presenting one number and hoping.

Check the adopted policy wording rather than a summary, and check whether the authority has a supplementary planning document that puts numbers to it.

Designing for the standard you will be judged against

The gap between planning submission and Building Regulations submission is often a year or more, and the standard can change in between.

Three habits protect the scheme. Design the fabric to the standard you expect to be in force at construction rather than the one in force at planning, because fabric is the hardest thing to change later. Keep enough space in the drawings for plant you may need but have not committed to. And avoid describing a specific technology in the description of development or in a condition, because a condition naming a particular heating system is a condition you will pay to vary.

Illustrative example: a scheme of 30 flats consented in one year with gas boilers shown on the drawings and no external plant space. By the time the building regulations application is made, the strategy has to change to heat pumps, and there is nowhere on the drawings to put them. The variation costs a fee, eight weeks and a redesign of the roof.

Following how these standards move is easier through the planning law updates timeline than by watching for individual statutory instruments, though the instruments themselves are the only authority.

This is general guidance, not legal advice; check the position with your local planning authority or a qualified professional before relying on it. PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval.