This UK home ventilation cost guide explains how to compare PIV, MVHR, bathroom and kitchen extractor fan projects, estimate running and maintenance costs, and request quotes that are genuinely comparable.
Overview
The cost of improving ventilation depends less on the equipment name than on the property, the installation route and the condition of the existing building. A straightforward extractor fan replacement may involve one appliance and an accessible electrical connection. A whole-house system can involve ductwork, ceiling access, controls, commissioning and making good after installation.
For that reason, a useful estimate should separate the project into four parts:
- Equipment: the fan, PIV unit, MVHR unit, grilles, filters, controls and any accessories.
- Installation: labour, electrical work, ductwork, roof or wall terminals and access equipment.
- Building work: cutting openings, lifting floors or ceilings, boxing-in, plastering, decorating and waste removal.
- Aftercare: commissioning, filter replacement, inspection, cleaning and repairs.
This approach is more reliable than searching for a single average figure. Two homes may need the same type of system but receive very different quotes because one has accessible loft space and the other has limited access, long duct runs or several occupied rooms that require careful scheduling.
The best ventilation system for a house also depends on the problem being solved. Local moisture in a bathroom may need an effective extractor fan. Persistent condensation across several rooms may justify a whole-house approach. A decision between PIV and MVHR should consider the property layout, airtightness, heat-loss priorities, available space and the level of disruption acceptable to the household. See our guide to MVHR versus PIV for a broader system comparison.
How to estimate
Start by writing a short project definition before asking for prices. Include the property type, number of bedrooms, affected rooms, visible symptoms and any known constraints. Take photographs of existing fans, vents, the consumer unit, loft access and areas where mould or condensation appears. This helps an installer identify likely access and electrical requirements before visiting.
Use this simple estimating formula:
Total project cost = equipment + installation labour + materials and access + building work + commissioning − included discounts or grants, where applicable.
Do not treat a product-only price as an installation estimate. The quote should state whether it includes:
- removal and disposal of the old equipment;
- new ducting, external terminals, grilles and backdraught protection;
- electrical isolation, wiring, switches, controls and testing;
- loft boards, access platforms, scaffold or other access requirements;
- repairs to holes, ceilings, walls or roof coverings;
- commissioning, airflow checks and user instructions; and
- VAT, if applicable, plus any call-out or survey fee.
For a bathroom extractor fan installation cost, the main variables are usually the distance to an external wall or roof outlet, the condition of the existing ducting, electrical access and whether the fan must be replaced with a different size or control arrangement. A kitchen extractor fan replacement may also require consideration of grease, existing duct restrictions, recirculation versus external discharge and the position of cupboards or a hob.
For PIV system installation, ask whether the proposed unit will be located in the loft or another suitable area, how the incoming air will be filtered, where the diffuser will sit and whether the loft needs additional ventilation or preparation. For MVHR installation UK projects, request a clear drawing showing the unit position, supply and extract points, duct routes, condensate arrangements, controls and service access.
Inputs and assumptions
A repeatable estimate should record the assumptions behind every quote. The following checklist gives you a practical starting point.
Property and access
- House, flat, bungalow, converted property or new-build home.
- Number of floors, bedrooms and wet rooms.
- Loft, ceiling, cupboard and service access.
- Distance between fans, the ventilation unit and external terminals.
- Whether residents, tenants or neighbouring properties will be affected during the work.
System scope
- One-room extractor, several local fans, PIV, MVHR or another whole-house ventilation system.
- Number and type of wet rooms requiring extraction.
- Whether existing ductwork can be reused or needs replacing.
- Required controls, such as timer, humidity sensing, boost or remote control.
- Noise, appearance, filter access and maintenance preferences.
Running and maintenance assumptions
Running costs depend on the appliance's electrical input, how many hours it operates, the electricity tariff and the selected control settings. A simple comparison is:
Annual electricity cost = power in kilowatts × operating hours per year × electricity unit rate.
Use the rated power from the product documentation rather than assuming every fan or ventilation unit consumes the same amount. Intermittent extractors, continuous low-rate systems and boost settings will produce different results. An MVHR system may also have filter and service requirements that should be included in the household budget.
Maintenance costs can include filter purchases, cleaning grilles and ducts where appropriate, checking airflow, inspecting external terminals and repairing controls or motors. Ask whether the installer offers a ventilation maintenance service and what is included in each visit. The cheapest installation is not necessarily the lowest-cost option if filters are difficult to access or replacement parts are unavailable.
Worked examples
These examples show how to compare scope without relying on unverified market prices. Replace each blank with the figures from your own quotations.
Example 1: bathroom extractor replacement
Estimate: fan and controls (£___) + labour (£___) + ducting or terminal (£___) + electrical work (£___) + making good (£___) = quoted total £___.
Check whether the quote includes removal of the old fan, a suitable external discharge route, airflow testing and disposal. If the installer proposes reusing existing ducting, ask whether it has been inspected and whether its size and condition are suitable for the replacement fan.
Example 2: PIV installation for a condensation problem
Estimate: PIV unit and diffuser (£___) + loft preparation (£___) + electrical connection (£___) + installation (£___) + commissioning (£___) = quoted total £___.
Record what the system is expected to address and what it cannot address. Ventilation can help manage moisture, but leaks, penetrating damp, rising damp, inadequate heating, defective gutters and building defects need separate investigation. For wider condensation advice, see our room-by-room guide to condensation and mould prevention.
Example 3: whole-house MVHR project
Estimate: MVHR unit (£___) + ductwork and terminals (£___) + design and installation labour (£___) + electrical and condensate work (£___) + access and making good (£___) + commissioning (£___) = quoted total £___.
Compare the design, not only the unit. A lower quote may exclude duct insulation, difficult routes, balancing, controls or post-installation adjustments. Ask each installer to price the same rooms and provide the same deliverables so the comparison is fair.
When to recalculate
Revisit your home ventilation cost estimate whenever a key input changes. This includes a change in electricity tariffs, a revised property layout, new loft insulation, replacement windows, an extension, a renovation that affects airtightness or a decision to add more rooms to the system.
Recalculate before accepting a quote if the survey reveals inaccessible duct routes, damaged roof or wall finishes, an inadequate electrical supply or building defects. Also ask for an updated figure if the specified model, control package or external terminal changes. A written variation is preferable to relying on a verbal estimate.
For a practical quote comparison, place each installer’s response in a table with these headings: system type, rooms served, equipment model, ductwork, electrical work, access, making good, commissioning, warranty, maintenance, VAT, exclusions and total. Then ask:
- What problem is the design intended to solve?
- How will airflow be measured and adjusted?
- Which parts require regular cleaning or replacement?
- What happens if concealed access or additional building work is needed?
- Who will provide instructions, certificates and aftercare?
Keep the completed table with your property records and update it when prices, equipment or the scope changes. For further planning, compare the options in our guide to choosing a home ventilation system, then request a survey-based quote rather than relying on a headline installation figure.
