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Published by Mo's Plumbing and Heating
How Much to Fit a Boiler, Labour Only?
You have found a boiler online, or you already have one, and you want somebody to fit it. That is a legitimate way to do this and plenty of installers will quote for it. What it changes is not mainly the price, it is where the responsibility sits when something goes wrong, and that is worth understanding before ordering anything.
The Short Answer
Labour only means you supply the appliance and the installer supplies the work, the flue kit, the fittings and the certification. It is priced on the same things that drive any installation: the flue route, whether the boiler moves, the state of the existing system and the gas supply. The saving comes from buying the appliance yourself, and the trade-off is that if the appliance is wrong, faulty or unsuitable, that is now your problem rather than the installer's. We price this job on a survey rather than from a list, because the work varies far more than the appliance does.
What Labour Only Actually Covers
Worth being precise, because the phrase suggests a smaller job than it is and quotes differ mostly in what they include rather than in the labour rate.
It normally covers removing and disposing of the old appliance, fitting the new one, the flue kit and its installation, the fittings, valves and any pipework alterations, flushing and dosing the system, commissioning the appliance, and the Gas Safe notification and Building Regulations paperwork.
So the appliance is the only thing you are supplying, and it is a smaller share of the total than most people expect. A quote that looks high against the boiler price you paid is usually not overpriced; it reflects that most of an installation is not the box.
Things worth confirming are in or out before agreeing anything: the flue kit, which is a real cost and is sometimes assumed to come with the boiler when it does not; a system filter, which most manufacturers now expect; a power flush if the system needs one; and making good afterwards where an old back boiler or cylinder has come out.
The Warranty Question
This is the part that matters most and it is the one people find out about afterwards, so it is worth going into properly.
Manufacturer warranties on domestic boilers generally require two things: installation by a suitably qualified and registered person, and registration of the appliance with the manufacturer within a set period after installation. Labour only satisfies both perfectly well, provided your installer is Gas Safe registered and registers it, so buying the appliance yourself does not automatically cost you the warranty.
What it does change is the length of warranty available. Manufacturers commonly offer extended warranties, sometimes considerably longer, where the appliance is both supplied and installed by an accredited installer of that brand. Buying the boiler yourself often means the standard warranty rather than the extended one, and over a decade that difference can be worth more than the saving on the box.
Terms vary by manufacturer and change over time, so the sensible move is to read the specific warranty terms for the specific model before ordering, and to ask your installer whether they are accredited for that brand and what that would add. We are manufacturer certified for Worcester Bosch, Vaillant, Baxi, Ideal and Vokera, which is worth asking about rather than assuming either way.
One thing that is not in doubt: whoever installs it must be on the Gas Safe Register, and the installation must be notified. That is a legal requirement rather than a warranty condition, and it applies identically whoever bought the appliance.
Where the Responsibility Moves
This is the real trade and it is worth seeing clearly, because it is not about trust or goodwill, it is about who holds the contract for what.
On a supply and fit job, the installer is responsible for the appliance and the work together. If the boiler is the wrong size, if it arrives damaged, if it fails in week three, that is one company to call and it is their problem to resolve.
On labour only, that splits. The appliance is between you and whoever sold it. The installation is between you and the installer. If a fault appears, the first question becomes whether it is an appliance fault or an installation fault, and you are the person standing between two parties who each have a reason to say it is the other one.
In practice most jobs are fine and this never arises. When it does arise it is awkward, and it is the honest reason installers price supply and fit the way they do rather than a markup for its own sake.
The other consequence is sizing. On a supply and fit job the installer sizes the appliance and carries the consequence of getting it wrong. If you buy the boiler, you have made the sizing decision, usually before anyone has seen the property.
Before You Buy the Appliance
Four things worth checking, and checking them first turns most of the risk above into nothing.
- Get the sizing confirmed rather than guessing from the old boiler's output. Boilers are commonly oversized, and copying the existing figure carries forward somebody else's mistake. On a combi the hot water demand and the incoming mains flow rate matter as much as the heat requirement.
- Check the boiler physically fits and the flue can go where it needs to. Case dimensions and flue positions differ between manufacturers and between models within a range, so a unit that suits the space on paper may not suit the existing hole.
- Confirm the flue kit is included and is the right one for your route. This is the single commonest gap between what people order and what they need, and the kit for a long or vertical run is a separate item.
- Ask an installer to look before you order, not after. Most will, and a survey that costs nothing is considerably cheaper than a boiler that turns out to be the wrong shape for the cupboard.
When an Installer Will Decline
Worth knowing so it is not a surprise, and none of these are awkwardness.
An appliance that is clearly the wrong size or type for the property. Fitting a boiler somebody knows is unsuitable makes them responsible for the outcome, and no reasonable installer will take that on.
An appliance bought from an unclear source, or one arriving without full documentation and a serial number that registers with the manufacturer. Without that the appliance may not be warrantable at all, which puts the installer in an impossible position later.
A system that needs work the customer does not want to pay for. Fitting a new appliance onto a heavily sludged system without cleaning it will damage the new boiler and most warranties expect the system to have been cleaned and dosed.
And second-hand or reconditioned appliances, which most installers will not touch, because the history is unknown and the liability is not.
If somebody declines your job, it is usually worth asking why rather than simply calling the next number. The answer is often something that would have caused you a problem later.
The Boiler That Does Not Fit the Flat
The specific way this goes wrong in this city is a sizing and shape mismatch rather than anything about the work, and it happens often enough to be worth naming.
Boilers bought online are usually chosen on output and price. In a Glasgow flat the binding constraints are frequently neither: it is whether the case fits the kitchen wall unit it has to live in, and whether that model's flue outlet lines up with the hole that already exists in a tenement gable. Flue positions vary between manufacturers and between models in the same range, so a boiler that is dimensionally similar can still need a new core drill through a sandstone wall, which is a different job from the one that was quoted.
The output side goes wrong in the other direction. A combi sized for a family house is frequently more than a one-bathroom flat can use, and on a combi the useful output is limited by the mains flow rate arriving at the property, which in an upper-floor tenement flat can be modest. Paying for a larger appliance than the incoming supply can feed is money spent on performance that will never appear at the tap.
Both are avoidable by having somebody look before ordering. That is the whole argument for a survey on a labour only job, and it is why we will look and give you a fixed price for the work rather than quote a fitting figure down the phone. On this housing stock, a fitting price given without seeing the flue route is a guess, and guesses on this job move in one direction.
When to Call Someone Out
Worth calling before you order the appliance rather than after, because the sizing, the case dimensions and the flue route are what decide whether the boiler you are looking at is the right one, and all three want checking on site. We will survey and give you a fixed price for the work, and we will tell you honestly if the appliance you have chosen is unsuitable rather than fitting it and leaving you with the consequence. Mo and Muhammad are Gas Safe registered for domestic work, and the installation is notified and the appliance registered with the manufacturer whoever bought it. If you would rather we supplied the boiler as well, ask what the warranty difference would be, since on some brands it is substantial.
Boiler Installation in GlasgowCommon Questions
Yes, and plenty of installers will quote for it. The installation must still be carried out by someone on the Gas Safe Register and notified, exactly as it would be otherwise. What changes is where responsibility sits if the appliance turns out to be faulty, wrong or unsuitable, which becomes your side of the line rather than the installer's.
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