MVHR in Ireland — Mechanical Ventilation with Heat Recovery, Cost, and Why You Need It

MVHR (Mechanical Ventilation with Heat Recovery) in Ireland: €4,000–€8,000 installed. Recovers 70–90% of the heat in the air you'd otherwise throw away. Two fans, a heat exchanger, intake and extract ducts. Mandatory for airtight homes (Part L 2022: 1–3 m³/m²·hr at 50 Pa; BER A1: 1–2; Passive House: ≤0.6). Without MVHR, an airtight home has stale air, condensation, and mould. Best paired with a heat pump — the recovered heat goes into the heat pump's hot water cylinder. Sizing: based on floor area and number of wet rooms. Typical 150 m² house: 3–4 bedrooms, 2–3 bathrooms, kitchen. Unit sized 250–350 m³/h. The ductwork must be designed at the same time as the house design, not retrofitted.

TL;DR

• MVHR in Ireland: €4,000–€8,000 installed. Recovers 70–90% of the heat in the air you'd otherwise throw away. Mandatory for airtight homes.

• Best paired with a heat pump. Without MVHR, an airtight home has stale air, condensation, and mould.

• Sizing: based on floor area and number of wet rooms. Typical 150 m² house: 3–4 bedrooms, 2–3 bathrooms, kitchen. Unit sized 250–350 m³/h.

When this matters most

You're at design stage and need to specify the ventilation.

When this doesn't apply

The MVHR is commissioned.

Frequently asked questions

How much does MVHR cost in Ireland?

€4,000–€8,000 installed. Plus ductwork design and installation, which is typically included. For a 150 m² house: €5,000–€7,000.

Do I need MVHR in an airtight house?

Yes. Without MVHR, an airtight home has stale air, condensation, and mould. MVHR is mandatory for Part L 2022 airtightness targets.

What size MVHR do I need?

Based on floor area and number of wet rooms. Typical 150 m² house (3–4 bed, 2–3 bath, kitchen): 250–350 m³/h unit. Engineer sizes based on the room-by-room air flow requirements.

Sources

Building Regulations 2023, TGD-F (Ventilation). https://www.gov.ie/