Garden village · Plymouth

Sherford New Town — 180-plot transition phase

Vistry & Persimmon JV transition phase to FHS spec

Get a similar quote More case studies

180

Total plots

768 kWp

PV capacity installed

House types

180

HEM models run

Vistry & Persimmon JV. 180 plots in the FHS transition phase delivered to Part L 2026 spec ahead of the regulatory deadline. Mix of 3-bed and 4-bed types with 3.4–6.0 kWp arrays. Full SAP and HEM dual-route modelling.

The brief

Sherford New Town is the South West's flagship garden village — a Vistry & Persimmon Joint Venture delivering 5,500 homes over 20 years on the eastern edge of Plymouth. The 180-plot 2026 phase needed Part L 2026 spec delivered ahead of the March 2027 mandate, with both SAP 10.3 and HEM compliance modelling to satisfy the dual-route transition period and provide future-proofing for buyer EPC requirements through to first re-sale.

House types and system specification

Six house types across the 180 plots: 40 × 3-bed terrace (3.4 kWp), 60 × 3-bed semi (3.4 kWp), 40 × 4-bed semi (4.4 kWp), 20 × 4-bed detached (5.2 kWp), 12 × 4-bed executive detached (6.0 kWp), and 8 × 2-bed apartment in two 4-flat blocks (2.8 kWp communal arrays sized to building-attributable ground floor). LONGi Hi-MO 5 425W panels, SunSynk hybrid inverters with battery-readiness, 8 kW Daikin Altherma 3 R ASHPs. MVHR specified across all house types — required to manage the tightened air permeability target.

Dual SAP/HEM modelling approach

Every plot modelled in both SAP 10.3 (Elmhurst Design SAP toolset) and HEM (BRE Home Energy Model engine). This dual-route approach was driven by the Approved Inspector's preference for SAP during the transition (familiar pathway) and the buyer-side need for HEM-modelled EPC scores after the 24 March 2028 SAP retirement. Total modelling hours: ~280 across the 180 plots (1.5 hours per plot for SAP, plus 0.5 hours for HEM cross-check). HEM models cached for plot variants — house-type 3-bed semi modelled once, applied to all 60 plots of that type.

Programme integration

Solar PV installation programmed between roof tiling completion and second-fix internal works — a 3-week window per plot. Factory pre-fit on roof cassettes was not used at Sherford (different roofing contractor preferences); instead, on-roof installation with 2-person crews moving between plots in 6-plot sub-batches. Site labour averaged 9 person-hours per plot. ASHP outdoor units installed during second-fix; indoor cylinders and controls during final-fix.

Compliance results

All 180 plots achieved DER ≤ TER on both SAP and HEM compliance routes. Average DER/TER margin: 14% on SAP, 11% on HEM (HEM is the more demanding calculation due to its half-hourly dynamic simulation vs SAP's monthly average). EPC scores averaged 89 (mid band A). Building Control sign-off achieved within 14 days of completion on every plot.

Result and Phase 2

180 units handed over within the JV's 2026 sales programme. Air permeability average 2.7 m³/(h·m²), comfortably below the FHS 3 target. Buyer-side: average heating bill estimated 65% lower vs an equivalent 2021-spec home at 2026 ASHP tariffs. Phase 2 (a further 220 plots) commissioned on the back of phase 1 performance — same pricing model, same house-type set, expanded HEM model library.

More projects

Volume developer · Cambridge

Eddington Phase 4 — 240-plot urban extension

Volume developer · Basingstoke

Manydown Garden Communities — 120-plot first phase

Eco-town · Bicester

Bicester Eco-Town extension — 95 plots

40% of ground floor area

PV / ground floor area

Mar 2027

FHS in force

75%

CO₂ vs 2013 baseline

£4,350 per dwelling

Per-plot premium

For developers and housebuilders

The garden village segment for volume new-build programmes

Per-plot pricing locked at procurement. Factory pre-fit on panelised roof cassettes. SAP/HEM modelling for every house type included. NHBC, LABC, Premier and Buildmark warranty-accepted workmanship. 20-year insurance-backed system warranty. We work with developers from 50 plots to 5,000+ across multi-site frameworks — agreed pricing, agreed programme, agreed warranty stack.

Developer hub →

How this fits into the FHS compliance pathway

Every FHS-compliant new build must pass three regulatory gates. The garden village segment fits primarily into the second gate — design-stage Part L compliance — but has knock-on implications for Building Control sign-off and post-completion warranty:

1
Planning permission Most solar PV on new dwellings is consented within the dwelling\'s primary planning consent. Conservation Areas, Article 4 directions and listed-curtilage plots require additional planning consideration — we handle the planning evidence required for these.
2
Building Control — Part L compliance SAP 10.3 or HEM compliance modelling demonstrating Dwelling Emission Rate ≤ Target Emission Rate. PV specification, ASHP capacity, fabric U-values and air permeability all entered into the modelling. We provide the full compliance file ready for the Approved Inspector.
3
Post-completion — warranty & EPC MCS certificate, EPC, monitoring app onboarding and 20-year insurance-backed workmanship warranty. NHBC, LABC, Premier and Buildmark all accept our installation specification without query — important if you\'re relying on a structural warranty for buyer mortgageability.

For a fuller walkthrough of the compliance process, see our Part L 2026 page and the FHS PV calculator which sizes a compliant system from your ground floor area in 30 seconds.

Frequently asked

Developer & contractor questions

Answers to the questions we get most often when discussing the garden village segment with new clients.

How does FHS affect per-plot pricing for volume housebuilders?

Per-plot pricing is the dominant procurement model for FHS-compliant solar across UK housebuilders. The typical structure is a fixed per-plot price (covering supply, install and warranty) negotiated at land-bid stage, locked with inflation cap to a delivery window of 24–36 months. For a typical 3-bed semi, volume per-plot prices in 2026 run £4,800–£5,600 depending on site size, plot mix and supplier framework. Above 500-plot bulk orders unlock further discount through factory pre-fit programmes.

What's the contractor risk of getting FHS specification wrong?

Material — both at completion (Building Control refusing sign-off) and post-completion (NHBC reserving warranty against undersized systems). Specifications below the deemed-to-satisfy 40% PV threshold require enhanced fabric calculation backing in the SAP/HEM file. We see contractors most often caught out on (a) air permeability — design target of 3 missed at 5–6 due to detail failures; (b) ASHP sizing mismatched to building heat loss; (c) PV array placement that doesn't hit the 40% requirement on geometry grounds.

When does the Future Homes Standard come into force?

24 March 2027 in England, with a 12-month transitional period running to 24 March 2028 for projects already under construction. The Approved Documents L and F were published on 24 March 2026 (Government statement HCWS1445), giving the industry exactly 12 months of certainty before regulatory commencement. Scotland, Wales and Northern Ireland are following with broadly equivalent regulations on roughly aligned timetables, although devolved nuances apply — Welsh regulations are typically 6 months ahead.

What does FHS-compliant solar PV actually cost per plot?

The Government Impact Assessment puts the total FHS premium at ~£4,350 per dwelling per dwelling (2025 prices, weighted average across heat pump, solar PV, MVHR and enhanced fabric). Of that, solar PV is roughly £4,200 — covering ~3.4 kWp for a typical 3-bed semi (panels, in-roof mounting, inverter, monitoring, MCS certification and 20-year insurance-backed warranty). Larger dwellings cost proportionately more; volume procurement reduces per-plot cost by 20–25%.

FHS 2027 deadline approaching

Get an FHS-compliant solar quote in 48 hours

Tell us your plot details — ground floor area, location and target start-on-site date. We return a fully-costed system sized to Part L 2026 (40% PV rule), with the SAP/HEM compliance pack included.

Get my free quote Try the FHS calculator 📞 0330 088 5421