How to Prepare Your Bathroom for the Future Homes Standard 2026
The Future Homes Standard is the 2026 step-change in Building Regs L (energy) and F (ventilation). For a renovating homeowner, the bathroom is the room that touches the most FHS levers in one go — hot water, ventilation, fabric and water demand. Get these four right at renovation and you avoid a £4,000-£8,000 retrofit when the rules harden.
Planning the work? Check what it usually costs, or work out your own estimate. The free quote form is at the top of this page.
Four FHS Levers Every Bathroom Touches
The Future Homes Standard pushes UK new-build emissions toward 75-80% lower than 2013 baseline by 2026. For renovations, the same levers are the smart targets at refurb stage — far cheaper now than retrofit.
Specify a 180-250 L unvented cylinder with twin coils & immersion. Works with current combi today, ready for ASHP swap tomorrow.
Basin tap ≤8 L/min, shower ≤9 L/min, dual-flush WC 4/2.6 L. Hits the FHS 105 L/person/day household target.
Continuous-running dMEV at 8 L/s, or MVHR branch with insulated duct. Replaces noisy intermittent fans and meets Part F 2026.
Add 80-100 mm PIR behind the tile-backer board on external walls. Negligible footprint cost, big U-value win.
The 7-Step FHS-Ready Bathroom Renovation
Step 1 — Audit current spec (Day 0)
Note the existing boiler type, hot-water demand, extract fan rating and external-wall construction. This drives the upgrade list.
Step 2 — Choose hot-water route (Week 1)
If you're on a combi, plan for a future move to ASHP + cylinder. Pre-route 22 mm cold and 28 mm primary feeds even if the cylinder isn't installed yet — first-fix only adds £180.
Step 3 — Specify low-flow brassware (Week 1)
Pick TMV3 thermostatic mixers with flow regulators. Hansgrohe EcoSmart, Grohe SilkMove ES and Ideal Standard EcoTherm all hit the FHS targets.
Step 4 — Plan the MVHR / dMEV branch (Week 2)
Specify Vent-Axia Lo-Carbon Sentinel Kinetic or equivalent. Insulated duct (25 mm) where it crosses cold zones. dMEV must run continuously at 8 L/s with 26 L/s boost.
Step 5 — Insulate behind the tiles (Week 2)
Replace plasterboard on external walls with 80-100 mm PIR + 12 mm tile backer (e.g. Marmox or Wedi). U-value drops to ~0.18 W/m²K — meets 2026 spec.
Step 6 — LED Part L lighting (Week 3)
≥75 lumens/watt fittings, 2700-3000 K, IP44 in zone 2, IP65 in zone 1. Notify under Part P (your electrician's scheme).
Step 7 — Commission & document (Week 4)
Ask for the air-flow test certificate (Part F), the Building Regs notification (Part P), and a written list of brassware flow rates. File these with your EPC for resale.
What FHS-Ready Adds to a Standard Bathroom Refurb
| Upgrade | Standard 2025 cost | FHS-ready 2026 cost | Net premium |
|---|---|---|---|
| Hot water (cylinder pre-pipe) | £0 | £900 – £1,600 | +£1,200 avg |
| Low-flow brassware | £450 | £550 – £800 | +£200 avg |
| Continuous dMEV / MVHR | £90 fan | £340 – £690 | +£420 avg |
| External-wall PIR | £0 | £550 – £950 | +£700 avg |
| Total premium | — | — | £1,800 – £3,500 |
Avoids a future retrofit estimated at £4,000-£8,000 once the gas-boiler ban hardens from 2028 and FHS Part L applies to extensions/material renovations.
Future Homes Standard Bathroom FAQ
FHS is mandatory for all new dwellings from 2026 in England. For renovations, Building Regs Part L1B and Part F still apply and are tightening in step — pre-empting FHS spec at renovation stage is far cheaper than retrofitting later.
Household design target: 105 litres per person per day. Means basin taps ≤8 L/min, showers ≤9 L/min and dual-flush WCs at 4/2.6 L. Most reputable brassware ranges have FHS-compliant variants.
No. Modern dMEV units (Vent-Axia Lo-Carbon, Nuaire Cyfan, Greenwood CV2GIP) run at 19-23 dB continuously — quieter than ambient. They only ramp up on humidistat or PIR trigger.
No — all four FHS upgrades are internal. Building Regs apply (Part L, F, P) and your installer notifies under Competent Persons Schemes.
Hard data is still emerging, but EPC-A and FHS-aligned features are showing 1.5-3% price premiums on 2026 listings, particularly for buyers concerned about future retrofit costs.
Compare Bathroom Quotes That Won't Fail at Year 7
BestBuilders matches you with up to 3 vetted bathroom fitters quoting on the same tanked + 15L/s extract spec.
Get FHS-Ready Bathroom Quotes — Free
We'll match you with vetted bathroom installers who specialise in FHS-aligned spec. Tell us your post-code and bathroom size — full written quotes typically within 4 working days.
Start your quote →