How Does a MVHR System Work?
How does a MVHR system work? In simple terms, it extracts stale, humid air and supplies fresh, filtered air while a heat exchanger recovers up to 90% of heat from the outgoing air. This keeps Irish homes comfortable, energy‑efficient, and healthy.
What Is a MVHR System?
A MVHR system (Mechanical Ventilation with Heat Recovery) provides controlled, continuous ventilation. It removes moisture and pollutants from wet rooms and delivers filtered air to living spaces. The system balances supply and extract airflows for a draught‑free, consistent climate.
Key components
Supply and extract fans
Heat exchanger core
Ductwork and valves
Filters and controls
Key Benefits of MVHR
Improves indoor air quality by removing moisture, allergens, and pollutants.
Prevents condensation and mould in kitchens, bathrooms, and utilities.
Recovers heat to reduce heating demand and bills.
Creates a balanced, draught‑free climate all year.
Supports Part F and NZEB compliance when designed and commissioned correctly.
MVHR vs traditional extractor fans
Extractor fans dump warm air outside and waste energy. How MVHR works is different: the heat exchanger pre‑warms incoming fresh air using outgoing exhaust air, improving comfort and efficiency.
Installation Timeline in Ireland
Retrofits: typically 3–5 working days, depending on access for ducts.
New builds: best during first fix so ducts sit within floors, ceilings, or walls.
Compliance and best practice
Work with NZEB‑certified professionals who follow Irish Building Regulations, DEAP, and ventilation best practice. Correct commissioning ensures balanced airflow and verified performance.
Discover How MVHR Can Work in Your Home
Now you know how an MVHR system works and why it suits airtight Irish homes. Ready to explore options? View our services
🌍 External Link
Official Irish Technical Guidance Document F – Ventilation (2019) on gov.ie
