Large-home specialist
Boiler sizing for large 4-bathroom homes in Bath
A large Bath home with four bathrooms and a family of five is not a combi job. It needs a properly sized system boiler, a 250–300L unvented cylinder, and 22mm distribution pipework designed for simultaneous demand.
For: Owners of large detached and townhouse properties
Where standard sizing fails
'One boiler fits all' rules of thumb break down over three bathrooms. We model simultaneous outlet demand — shower, bath, kitchen tap — and size the cylinder recovery to match your worst-case morning.
Included in a large-home design
- Simultaneous-demand model on your actual outlet count
- System boiler sized on recovery, not headline kW
- 250L+ unvented cylinder with high-output coil
- 22mm pipework audit and upgrades where undersized
- Weather compensation and zoning built in
Frequently asked
- Can I put a second combi in instead?
- Rarely a better answer. Twin combis double maintenance and lose the simultaneous-demand benefit of a proper system + cylinder.
- What if I want a bath filler at high flow?
- That needs a strong mains supply and a high-flow cylinder outlet. We test both and specify accordingly.
- Is space an issue?
- A modern 250L unvented is roughly 1.7m tall by 600mm — most Bath homes have a plant room, garage corner or airing cupboard for it.
Book a large-home survey
Tell us bathrooms, occupants and shower types. We'll model demand and quote the right boiler-plus-cylinder combination.
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