Project work
Heating for extensions and new builds
The question we're asked most on extensions is whether the existing boiler will cope. It usually can — but only if the answer is worked out from added heat loss rather than assumed either way.
For: Self-builders and extenders
Capacity and zoning
A well-insulated modern extension adds surprisingly little load, so a boiler swap often isn't needed. What does need thought is zoning: a large glazed extension has different response characteristics to the original rooms, and putting it on the same circuit with no separate control leads to overheating one and starving the other.
What we handle on these projects
- Added heat loss calculated against the existing boiler output
- Separate zone or underfloor circuit with its own control
- First fix coordinated with the builder before screed or boards
- Commissioning, balancing and Building Regs notification at completion
Frequently asked
- Will my boiler need replacing?
- Frequently not. We'll tell you honestly if the existing one has headroom.
- Underfloor or radiators in the extension?
- Underfloor suits large glazed spaces and solid floors well, and runs at lower flow temperature — which pairs nicely with a condensing boiler.
- When should we bring you in?
- At drawing stage. Pipe routes are free on paper and expensive in a finished screed.
Plan the zoning early
Extensions rarely fail on boiler capacity; they fail on control strategy. Getting the zoning right at first fix costs nothing extra.
Related solutions
Core services
Where we cover
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