As Passive House architects, we are often tasked with the thermal upgrading of a older house (or building).
There has been much in the news recently about the value of Air Source Heat Pumps (ASHP’s). And in the right house, these are fab – low running costs, no reliance on fossil fuels at source, low carbon.
However, ASHP’s only work in buildings that have a low thermal requirement ie houses that are low energy. As they only heat radiators to low temperatures (traditional radiators are higher), you may find that the ASHP needs to work harder, resulting in higher energy bills.
Our advice? Upgrade the thermal performance of your house before considering upgrading to an ASHP. Because if your house is not insulated to a good enough standard, it will cost you more money to heat your house.
Note – if you are upgrading the thermal performance of your house, a ventilation system is essential for your health, and the health of your house.