Approved Document F of the Building Regulations for Ventilation is changing and comes into effect on 15th June 2022.

It forms part of the Government response towards the introduction to the Future Homes and Buildings Standard in 2025, covering energy efficiency, ventilation, and overheating.

The guidance in Approved Document F, Volume 1 applies only to dwellings. For blocks of flats with shared communal rooms, Approved Document F, Volume 2: Buildings other than dwellings should be consulted.

The 2022 updates to Approved Document F introduce stricter ventilation standards for UK dwellings, effective from 15th June 2022. Key changes include reclassified ventilation systems, higher whole-dwelling airflow rates (minimum 0.3l/s per m² or 13l/s + 6l/s per bedroom), mandatory airflow testing for mechanical systems, and a 73% minimum heat recovery efficiency for MVHR units. These revisions align with the Future Homes Standard 2025, prioritising energy efficiency and indoor air quality.

The 2022 Ventilation Revolution: What You Need to Know

The UK’s Building Regulations Part F has undergone its most significant overhaul in a decade. For builders, architects, and homeowners, these changes aren’t just bureaucratic tweaks—they’re a seismic shift in how we approach airflow, damp prevention, and energy efficiency. Let’s break down what’s new, why it matters, and how to stay compliant without losing your sanity.

The Death of System 1-4: Simplicity Wins

Gone are the days of confusing “System 1” or “System 4” classifications. The 2022 regulations streamline ventilation into three clear categories:

1. Natural Ventilation

   • For: Less airtight homes (design air permeability >5m³/h/m²).
   • Requirements: Intermittent extract fans in wet rooms (kitchens, bathrooms) + trickle vents.
   • Extract Rates: Same as 2013 (e.g., 60l/s for kitchens without cooker hoods).

2. Continuous Mechanical Extract (MEV/dMEV)

   • For: All homes, especially those aiming for higher airtightness.
   • Boost Rates: 13–17l/s for kitchens, 8l/s for bathrooms.
   • Trickle Vents: Still required but smaller (4,000–10,000mm² per room).

3. Mechanical Ventilation with Heat Recovery (MVHR)

   • For: High-efficiency homes (airtightness <3m³/h/m²).
   • Key Changes:
     • Heat recovery efficiency ≥73% (up from 70%).
     • Balanced airflow (supply = extract) to prevent pressure issues.
     • Ductwork must minimise bends and length for optimal performance.

Whole-Dwelling Ventilation: Bigger Numbers, Cleaner Air

The new “whole dwelling” airflow rates are a game-changer. Forget one-size-fits-all—ventilation is now calculated using:

• Option 1: 0.3l/s per m² of floor area.
• Option 2: Bedroom-based rates (13l/s for 1-bed, +6l/s per extra bedroom).

Example: A 150m², 3-bed home needs 45l/s (150 x 0.3) or 31l/s (3-bed base rate). You pick the higher value—so 45l/s here.

Why This Matters:

• Older homes often had inadequate airflow, leading to mould and CO₂ buildup.
• New builds must now prioritise ventilation as rigorously as insulation.

Testing and Commissioning: No More Guesswork

From June 2022, all mechanical systems must undergo airflow testing using UKAS-accredited tools. Key steps:

1. Test Every Fan: Including cooker hoods and dMEV units.
2. Submit to Building Control: Proof of compliance is mandatory.
3. Handover Certificates: Homeowners get a ventilation “logbook” post-installation.

Penalty for Non-Compliance: Failed inspections, delayed sign-offs, and potential legal disputes.

MVHR Upgrades: Efficiency Meets Complexity

MVHR systems are now the gold standard, but the rules are tighter:

• Duct Design: Shorter, straighter ducts = better performance.
• Installation: Only competent technicians (e.g., NICEIC-registered) need apply.
• Heat Recovery: 73% minimum efficiency ensures less wasted energy.

Pro Tip: VENTI’s AUREN 160  unit hits 93% heat recovery efficiency—future-proofing against potential 2025 hikes.

The Hidden Challenge: Retrofitting Older Homes

For existing buildings, the regulations demand:

• Post-Retrofit Checks: Adding insulation? You might need extra ventilation (e.g., MEV fans).
• Window Replacements: New trickle vents compulsory unless MVHR is installed.

Actionable Advice for Stakeholders

1. Builders/Developers:
   • Use MVHR in high-spec projects; MEV for mid-range.
   • Factor in ductwork design early—avoid last-minute changes.
2. Homeowners:
   • Request airflow test certificates post-renovation.
   • Consider FLUXO systems for heat recovery + compliance.
3. Landlords:
   • Upgrade older rentals with dMEV to meet 2025 EPC targets.
   • Document all ventilation work for tenancy audits.

Why VENTI’s FLUXO, AUREN and ARIA Systems Are Future-Proof

• FLUXO 150: Exceeds 2022 heat recovery requirements (82% efficiency) and handles up to 17l/s.
• AUREN 160: 
• ARIA dMEV: Continuous humidity-sensing extraction, ideal for retrofit projects.
• Compliance Guarantee: All units come pre-tested to meet Part F airflow rates.