MVHR Design Service in Newbury: Expert Solutions for Town and Countryside

Mechanical Ventilation with Heat Recovery (MVHR) is a design-led discipline: good units alone won’t save energy or deliver healthy indoor air — the system, the ducting, the controls and the way it is integrated with the building fabric all must be engineered together. In Newbury and across Berkshire — where Georgian terraces, modern M4-corridor developments and remote barn conversions sit cheek-by-jowl — that engineering needs local nuance. Newbury’s position on the Thames Valley / M4 axis brings both development pressure and pockets of high outdoor pollution to consider; its countryside brings heritage constraints and practical retrofit headaches.

Why design matters here

A correctly designed MVHR system:

• meets Building Regulations (Part F — ventilation; and must be considered alongside Part L — conservation of fuel and power),

• matches whole-building airflow needs to real airtightness and occupancy patterns,

• minimises noise and draughts, and

• recovers as much heat as practically possible without creating condensation, cross-contamination or long-term maintenance burdens.

The Newbury mix: from historic market town to modern hub

The property spectrum

Newbury and the surrounding Thames Valley present a wide property palette:

• Rural cottages & barn conversions — often solid-walled, irregular plans, limited service voids and conservation constraints.

• Suburban / town houses — newer estates with variable airtightness and standard service zones.

• M4 corridor new builds and commercial developments — tight build programmes, high airtightness targets, larger plantrooms and corporate air-quality expectations.

Each typology alters the design priorities: duct routing and discreet external terminals for listed buildings; compact or decentralised MVHR for tight lofts or retrofits; high-performance units and properly sized ducts in airtight new builds.

Designing for rural retreats and suburban estates — the detailed tradeoffs

When you design MVHR for Newbury’s mix you must reconcile three technical tensions:

1. Airtightness vs ventilation need.
   MVHR delivers its benefits in air-tight fabric. That means designers must consider actual infiltration (blower door tests) and size systems to meet required whole-house ventilation rates — not a guessed number. Approved Document F gives the whole-dwelling criteria and explains how to use either bedroom count or floor area to set the minimum ventilation requirement.

2. Duct routing vs heritage constraints.
   In barn conversions and period homes you’ll typically lose the luxury of a neat loft run. The design choices are: route ducts through risers and wardrobes, use compact/room-by-room decentralised units where a central ducted system is impossible, or accept some exposed runs hidden cleverly behind joinery. Each has acoustic, maintenance and performance trade-offs. Guidance recommends minimising flexible duct length and favouring rigid smooth-bore ducting where possible to reduce pressure loss and noise.

3. External air quality & filtration.
   Proximity to the M4, industrial sites or local sources of dust (construction, farmyard, stables) will change intake siting and filter specification. Approved Document F explicitly asks designers to locate intakes away from pollution sources and to consider filtration where outdoor air quality is poor. In practice, that often means fitted fine-particle intake filters (e.g. ISO/ePM1 / F7 class) and carefully sited intakes with separation from exhausts and flues.

The design checklist we use in Berkshire

1. Brief & occupancy profile. Target ventilation strategy (continuous whole-house MVHR vs demand-controlled extracts), special uses (home office, workshops).

2. Fabric & site survey. Drawings, airtightness history (or test), loft and riser space, conservation constraints, intake/exhaust siting possibilities.

3. Regulatory sizing. Apply Approved Document F tables (whole-house ventilation and room extract rates) and check Part L energy interactions. Example: use the higher of the bedroom-based or area-based whole-dwelling criteria.

4. Room-by-room assignment. Allocate extract and supply branches (wet rooms as extract, living/bedrooms as supply) and size final runs to maintain suitable air velocities for low noise. Passivhaus and good-practice guidance recommend limiting primary duct velocities to ≈2–3 m/s and final runs to ≈1–2 m/s to keep noise low.

5. Duct network design. Use rigid smooth ducts where possible; minimise bends and long flexible runs; include balancing dampers and accessible access panels for commissioning and maintenance. Seal joints; meet BSRIA/BS standards for flexible duct use.

6. Unit selection & heat-exchanger choice. Choose counter-flow plate exchangers or rotary wheels depending on project priorities: plate exchangers give excellent sensible efficiency (commonly up to the high-80s/90% in lab conditions), rotors give high sensible + latent recovery and lower frost risk in some configurations — each brings different maintenance and cross-contamination considerations.

7. Controls & frost protection. Design summer bypass for cooling and frost-control strategy for winter (pre-heater, bypass/defrost sequences or rotor features). The chosen strategy must maintain supply temperature and avoid repeated frost cycles that reduce energy returns.

8. Filtration. Specify intake filters appropriate to the site (e.g., G4 pre-filter + F7 / ePM1 for PM2.5 protection in road-facing sites) and ensure ease of replacement.

9. Commissioning & handover. Deliver a ductwork static pressure & airflow test schedule, balancing reports aligned to BSRIA/CIBSE best practice and the Part F completion checklist. Commissioning is not optional — an uncommissioned MVHR performs poorly.

Accurate airflow calculations — a worked example (3-bed house)

Approved Document F offers two ways to set whole-dwelling ventilation: a bedrooms table and an area (floor-area × 0.3 l/s·m²) criterion. Use the larger figure.

• Suppose a 3-bed house (typical Newbury terrace) is 100 m² internal floor area.

  • Area method: 100 m² × 0.3 l/s·m² = 30.0 l/s.

  • Bedroom method (Table 1.3): 3 bedrooms → 31 l/s (the table number).

  • Design whole-house ventilation = 31 l/s (use the higher value).

Convert to MVHR unit sizing (units are commonly rated in m³/h):

• 31 l/s × 3.6 = 111.6 m³/h (because 1 l/s = 3.6 m³/h; 31×3.6 = 111.6).
  So you’d typically select an MVHR capable of delivering at least 112 m³/h at the design static pressure, and allow additional margin (fan curve headroom, filter loading, future changes) typically 15–25 % above the calculated need. For intermittent extracts (cooker hood use) follow the Part F intermittent rates (e.g. cooker-hood 30 l/s when ducted to outside, or 60 l/s if not).

Heat-exchanger selection — counterflow plate vs rotary wheel

• Counterflow plate exchangers: common in domestic MVHR; can achieve very high sensible recovery (lab figures often quoted up to ~85–95% depending on test conditions). They maintain strict separation of supply and extract airstreams (no rotary leakage).

• Rotary (thermal/enthalpy) wheels: offer high sensible and sometimes latent recovery (they can transfer moisture), can give slightly higher seasonal performance in some climates and are self-defrosting in certain designs — but they introduce small purge leakage between streams and usually require more careful purge-sector control.

Design choice depends on: target efficiency, need for latent recovery (humidity control), frost strategy, maintenance appetite and the requirement for total separation (e.g., medical/clean uses typically prefer plate exchangers).

Ducting, acoustics and pressure: the often-overlooked trio

• Keep it simple. Shorter runs, fewer bends and larger duct diameters reduce pressure drop and noise. Approved Document F and BSRIA stress minimising length and bends and using rigid ducts where possible.

• Noise targets. Design to keep supply noise in bedrooms at typical CIBSE/BS targets — in practice this means low terminal velocities and acoustic attenuators as required. Passivhaus guidance emphasises low duct velocities (≈1–2 m/s on final runs).

• Fan selection & headroom. Select a unit whose fan performance curve supplies the required flow at the calculated system static pressure; include margin for filter clogging, extra fittings and future changes. Practically, designers add 15–25% headroom.

Frost protection and summer cooling — practical choices for Berkshire

Newbury’s temperate maritime climate rarely demands extreme frost strategies, but any MVHR unit in exposed lofts or with high heat-exchanger effectiveness must plan for frosting. Common options:

• Pre-heater (electric/coil) to warm intake air so the exchanger doesn’t freeze (effective but increases energy draw).

• Bypass/defrost cycles — controlled bypass or rotor stop to protect exchangers; some systems use pressure or temperature differentials to trigger defrost.

• Summer bypass — bypass the exchanger when outside air is cooler than internal (true summer bypass must be automatic and consider internal vs external temperature).

We size / specify the frost strategy during design, not as an afterthought.

Our portfolio & examples from the Thames Valley

• Barn conversion near Speen — decentralised MVHR for two wings, discrete grilles, bespoke joinery voids and high-grade intake filtration because of nearby stables; achieved comfortable summer bypass and minimal visual impact.

• 3-bed new build in Newbury town — central loft-mounted unit, rigid low-loss ducting with acoustic attenuators, commissioning report showing balanced flows within ±5% of design targets.

• Mixed-use Thames Valley development — bespoke commercial MVHR design using enthalpy wheels to manage latent loads in shared amenity spaces, with intake siting moved off the busy frontage to meet Part F pollutant guidance.

FAQs for Newbury homeowners

Can you design MVHR for a barn conversion in the countryside?

Yes — but preparation is key. Barn conversions often lack standard service zones and may have strict planning/listed-building constraints. The options are: compact central units with routed risers, decentralised room units, or bespoke cabinetised duct routes. We always survey in person, check conservation consents and propose routes that minimise visual impact while preserving performance. Approved Document F and good practice guides recommend careful intake siting and filtration if local agricultural sources could introduce pollutants.

What is the cost of an MVHR design for a standard 3-bed home?

Costs vary by complexity and scope — design-only fees are commonly in the low hundreds to low thousands of pounds, while full system supply, installation and commissioning for a 3-4 bedroom home typically fall in the £3,000–£10,000 band depending on quality, ducts and access (new-build at the lower end, retrofit at the higher end). Commissioning is commonly charged separately (typically a few hundred pounds). For a simple guide: industry summaries and estimators list unit + duct + install + commissioning broadly in those ranges — we always provide a transparent, itemised quote after an initial site survey.

Do you provide design assistance for self-builders?

Yes. We offer staged services that suit self-builders: concept design and duct routes for planning and structural coordination; detailed layout and specification for tendering; and commissioning support. Many self-builders opt for a thorough 3D duct layout early in the build so joists and services can be placed around the ducts rather than vice-versa. Passivhaus and good-practice guides strongly recommend early design integration for airtightness and MVHR performance.

How long does a full design take?

Typical turnaround from brief to full design package varies with complexity — simple new-build dwellings: 1–2 weeks; complex retrofit or listed buildings: several weeks because of surveys, coordination drawings and approvals. (We’ll give a firm lead-time when you request a consultation.)

Why hire a specialist designer (short checklist)

• Regulation compliance: Part F sizing, intake siting, commissioning evidence all matter.

• Energy & comfort outcomes: A poorly sized or poorly routed MVHR can cost more to run and deliver worse IAQ than a properly designed extract system.

• Longer life & lower complaints: Proper duct sizing, acoustic design and commissioning drastically reduce occupant complaints and call-backs. BSRIA and CIBSE emphasise measurement and verification at handover.

Book a bespoke MVHR design consultation

If you’re in Newbury or anywhere in Berkshire and are planning a new build, retrofit or conversion, we’ll:

• run a no-obligation scoping call,

• follow with an on-site survey where required, and

• deliver a clear, itemised design proposal showing performance, ducting routes, unit selection, controls and an estimate for supply, installation and commissioning.

Request your bespoke MVHR design consultation today — we’ll tailor a pragmatic, regulation-compliant design that suits the character of your property (townhouse, barn conversion, or M4-corridor development).