What’s the best heating system to comply with ROI energy regulations?

What’s the cheapest alternative to meet the ROI Building Regulations’ renewables requirement for a new build? How about a retrofit?

In a new build situation, the payback with a heat pump should be three to five years at the most. The marginal cost of installing a heat pump, appropriate cylinder and potentially larger radiators is likely to be similar to the fossil fuel alternative. This is because a gas + connection to grid (and associated developer infrastructure) or oil + tank will require the addition of photovoltaics to comply with Part L of the Building Regulations.

Even though you can currently comply with Part L of the Building Regulations with a high efficiency boiler and solar thermal panels, (with a very high building fabric specification in every other respect), the spirit of the regulations is to encourage renewable heating sources. The upcoming changes to Part L will see this requirement become even more stringent with, possibly, the need for heat pumps and PV to be installed on all new builds.

In terms of retrofit, the economic case is slightly less generous. The catch is that the cost of a retrofit of this nature including the airtightness measures, the ventilation system and the heat pump is unlikely to be less than €15,000 (excluding other likely required insulation measures) and over the next 20 years this is about €3.75 per heating day, gobbling up about 50 to 70 per cent of the energy efficiency savings.

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Paul Kenny

Written by Paul Kenny

Paul is the CEO of the Tipperary Energy Agency

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