Return to learning centre
Should I replace my gas boiler with a heat pump?
January 5, 2024

Yes, replacing your existing gas boiler with an Air Source Heat Pump (ASHP) should save you money on your heating bills and lower carbon emissions, two good reasons! However there are wider considerations that could affect other aspects of your building including insulation and ventilation, improvements to both will help to make sure you get the best out of any central heating system. Get in touch with our qualified Architects who can guide you through the process.

Building Fabric

The fabric of your building, ie. the walls, floors, roof, windows, external doors, needs to be airtight and well insulated. You need to make sure the space you are trying to heat holds onto the warm air rather than letting it escape through the fabric to ensure the heat-pump is running at maximum efficiency. Upgrading or adding insulation could be a cost-effective way of improving the fabric. Replacing or resealing leaky windows and doors will improve air-tightness.


Air movement in buildings is required to maintain a comfortable environment for occupants. It provides fresh air to breathe and removes unwanted smells and excessive moisture. Too much ventilation and draughts will be felt, too little and the air will become stale. Moisture and limited ventilation are an ideal environment for mould to grow. The Building (Regulations) Scotland require for specific ventilation rates depending on the air-tightness value of the building.

Photo of a domestic sized air source heat pump outside a house
Domestic sized Air Source Heat Pump

Works undertaken to alter a building should comply with the Building (Regulations) Scotland and may also require a Building Warrant. At T.H.E. we are experts in gaining technical approvals and can make the required applications on your behalf.

It is also worth noting that from April 1st 2024, you will not be able to obtain a Building Warrant for a building heated by a ‘direct emission heating system’ which include gas boilers. This would also be the case if you were extending a building where the Building Warrant was obtained after April 2024. Ultimately it is hoped that Scotland could phase out fossil fuel boilers completely however the timeline and process for this is still unclear, read more here: Scottish government delays plan to phase out gas boilers – BBC News.

Not quite what you were looking for? Why not get in touch with one of our team who will be happy to answer any questions you have about making sustainable improvements to your building.

Looking for more information on planning for a green future? Why not check out our guide on how to design more sustainable homes.

Get in touch
Do you have initial ideas for your project but are unsure where to begin? Contact our team and we would be delighted to offer our assistance and expertise.
Contact Us