Radiator
Installation in
Watford
New radiators fitted neatly, sized correctly and balanced properly — so the whole house heats evenly and your boiler doesn't have to work overtime to make up for a cold room.
What radiator installation actually covers
What it is
Supply and install of new radiators, replacement of tired or leaking units, relocating radiators (e.g. to fit a new kitchen), rebalancing an entire system, and vertical / designer radiator installations.
Who it's for
Anyone with a cold room, a rusty or leaking radiator, a radiator in the wrong place, a bathroom needing a heated towel rail, or a whole-house upgrade paired with a boiler replacement.
When you need it
Any time — but ideally before winter, and always as part of a boiler replacement rather than after (so the new heat exchanger isn't contaminated by an unflushed old system).
Why professional help matters
A radiator that's too small heats slowly and never quite gets there. Too big, it short-cycles the boiler. Poorly balanced, one room boils while another stays cold. Getting this right is the difference between a house that feels warm and one that just costs more to heat.
The cost of leaving it
Radiators look simple. The pain of getting them wrong is not.
What can go wrong
- A leaking radiator can cause floor damage worth many times the cost of replacement — often invisibly, under carpet.
- An undersized radiator forces the boiler to run longer at higher temperatures — burning more gas and shortening its life.
- Fitting new radiators onto an unflushed old system voids most boiler warranties and dumps sludge into the new radiators within weeks.
- A poorly balanced system means paying to heat the hallway to 25°C so the back bedroom reaches 18°C.
Common mistakes we see
- Buying a radiator by size on the wall rather than by BTU output for the room.
- Reusing old valves — they're usually the first thing to fail, and much cheaper to replace during install.
- Not fitting isolation valves — turning off the entire heating just to swap a radiator later on.
- Skipping a system flush when adding new rads to an old system.
Our process
A clear, repeatable system — the same on every job, whether you're a homeowner or a landlord with a portfolio.
- 01
Heat loss check
Room-by-room sizing based on BTU requirement, not guesswork. Right output, right position.
- 02
Quote & spec
Fixed price for supply and install, radiator model, valve type and pipe route confirmed in writing.
- 03
Install day
Floors and furniture protected. Neat pipework, isolation valves fitted, radiator hung level, valves TRV'd unless stated.
- 04
Fill, vent, balance
System refilled with fresh inhibitor, air vented, and every radiator balanced on the lockshield.
- 05
Test & tidy
Full leak test, warm-up check on every radiator, waste removed. 12-month workmanship guarantee.
What you get
Correctly sized rooms
Every radiator sized on heat loss — no cold corners, no boiling hallways.
Neat, permanent pipework
Isolation valves fitted so future work never means draining the whole system.
Balanced system
Every radiator balanced so hot water reaches each rad at the right rate — genuinely even heat.
TRVs as standard
Thermostatic radiator valves fitted unless you specify otherwise, so unused rooms don't burn gas.
Protects your boiler warranty
System flushed and inhibited before new radiators are added — a manufacturer warranty requirement.
Backed by 12-month guarantee
All workmanship guaranteed for a year, in writing.
Recent radiator installation work
Photos from real jobs completed by Matt and the Premier Heating team.
In detail
Radiator work covers more than swapping like-for-like. Here's the range of jobs we do most weeks.
Sizing and heat loss
Radiator size is measured in BTU or watts of heat output, not centimetres on the wall. We calculate room heat loss based on window area, wall U-values, ceiling height and desired room temperature, then spec a radiator that hits that target at the boiler's design flow temperature — including at lower flow temperatures if you're planning a future heat-pump upgrade.
Types we install
Single and double convectors, low surface temperature (LST) radiators for bathrooms and nurseries, vertical radiators for tight walls, designer radiators, aluminium radiators for fast response, heated towel rails and dual-fuel towel rails, and cast-iron column-style radiators.
Valves and controls
TRVs (thermostatic radiator valves) as standard so rooms self-regulate; lockshield valves fitted opposite; isolation valves so future radiator changes don't need the whole system drained. Smart TRVs (Tado, Hive, Honeywell) available on request for room-by-room scheduling.
System flush and inhibitor
Any new radiator work includes at minimum a hot chemical flush of the affected zone and fresh inhibitor. Where the system is heavily contaminated we'll recommend a full powerflush before install — priced separately — to protect the new radiators and your boiler warranty.
Whole-system rebalancing
If some rooms are always too cold and others too hot, the answer usually isn't a bigger boiler — it's a properly balanced system. We can rebalance as a standalone job.
Frequently asked questions
How much does a radiator installation cost?
It depends on the radiator, the valves, the pipe route and whether we're replacing like-for-like or relocating. Every job is quoted in writing before we start. Rebalancing an existing system is priced separately.
Can you fit vertical or designer radiators?
Yes — we fit all types including vertical, column, aluminium, LST and heated towel rails.
Will you flush the system when fitting new radiators?
Yes — at minimum a hot chemical flush and fresh inhibitor. Where needed we'll recommend a full powerflush (priced separately) to protect your warranty.
Do you fit TRVs as standard?
Yes — thermostatic radiator valves are fitted unless you ask for manual valves. Smart TRVs available on request.
How long does a single radiator take to fit?
A like-for-like swap in the same location is usually 1–2 hours. Relocating a radiator or piping a new one from scratch takes longer and is priced individually.
Do you guarantee the work?
Yes — 12-month workmanship guarantee, plus the radiator's own manufacturer warranty.
Can you rebalance my whole system without fitting new radiators?
Yes — rebalancing is a standalone job. If you have hot rooms and cold rooms with the same-size boiler, this is usually the first fix to try.
Do you cover my area?
Yes — we cover Watford, Northwood, Rickmansworth, Pinner, Bushey, Hatch End, Stanmore, Middlesex and Greater London. If you're nearby but not listed, please call.
Related services
Areas we cover
Based in Watford, serving Hertfordshire and Greater London.
Need something not listed? Get in touch.
Cold rooms? Let's fix them.
Free on-site quote. Fixed price. Neat pipework, properly balanced, guaranteed.