The short answer: a gas hob is governed by gas safety law and an induction hob by the electrical supply. A gas hob must be connected by a Gas Safe registered engineer, who makes the gas connection, tests it for leaks and checks the room and the surroundings suit the appliance. An induction hob needs a supply that can carry its power rating, which for a full-size model usually means a dedicated cooker circuit rather than a plug. Both have to fit the same worktop, but the requirements that decide whether the job is simple or complicated come from very different places.
This explainer sets out the gas hob installation requirements one by one, then what an induction hob asks for instead, so you can see what is involved before choosing, and who needs to be involved if you are switching from one to the other.
Gas hob installation requirements, one by one
Who is allowed to connect it
Connecting a gas hob is gas work, and in Great Britain anyone doing gas work on domestic appliances for a living must be on the Gas Safe Register. The Health and Safety Executive states that anyone employed to work on gas appliances in domestic premises must be a Gas Safe registered engineer. Being registered is not quite enough on its own: engineers are qualified for particular types of appliance, and those competencies are listed on the back of their Gas Safe ID card. For a hob you want to see cookers or cooking appliances covered. You can also check an engineer on the Gas Safe Register website or by calling 0800 408 5500.
How the gas reaches the hob
A built-in gas hob sits in a worktop and is connected to a gas pipe that ends just below it. The industry installation standard for domestic gas cooking appliances, BS 6172, allows a built-in hob to be connected either with rigid pipework or with a flexible connector and a self-sealing plug-in device, as summarised in Gas Safe Register’s Technical Bulletin 036 for engineers. Some manufacturers specify one method only, and their instructions take priority. In practice this means the gas pipe has to end in the right place under the worktop, which may involve running pipework through the back of a base unit if the hob position has moved.
Testing once it is connected
Making the joint is the quick part. The engineer then checks the installation for gas leaks, confirms the hob is receiving gas at the right pressure, and lights each burner to check it burns correctly and that safety features such as flame-failure devices work. A hob that is fitted but not tested is not a finished installation.
Ventilation in the room
A gas hob burns gas in the open room, so the room needs fresh air. Manufacturers’ installation instructions set the ventilation requirement based on the British Standard for ventilation of gas appliances, BS 5440-2. A typical example, taken from one cooker manufacturer’s installation guide, asks for an openable window or equivalent in every case, adds a permanent air vent in small rooms, and rules out bathrooms, shower rooms and small bed-sitting rooms altogether. The exact figures depend on the appliance, so the engineer works from the instructions for your model. This is most likely to matter in compact kitchens, galley kitchens in flats and kitchens with no opening window.
Clearances around and above the burners
Open flames bring stricter clearances than an induction surface. Manufacturers set minimum distances from the burners to side walls, tall units and any combustible material, and a minimum height for a cooker hood above, which is usually greater for gas than for electric. A hob directly under a window with curtains or blinds, or tucked against a tall larder unit, may not meet those distances even if it physically fits the cut-out.
A small electrical supply as well
Most modern gas hobs have electric ignition, so they also need a low-power electrical connection, usually a plug into a socket or a fused connection unit within reach below the worktop. It is a small detail, but a kitchen with no socket in the right base unit will need one added.
What an induction hob asks for instead
An induction hob has none of the gas requirements: no flame, no ventilation calculation for combustion and no Gas Safe engineer. Its requirements are electrical, and the main one is capacity. A full-size induction hob can have a high maximum rating, so it normally needs a dedicated cooker circuit connected through a cooker switch and outlet plate. Some smaller or two-zone models come with a 13A plug and limit their power to suit it.
Where the kitchen has never had an electric hob or cooker, there may be no suitable circuit at all. Adding a new circuit is notifiable building work in England under Approved Document P, and whether the existing consumer unit has a spare way and enough capacity becomes part of the job. If you are not sure what kind of board you have, our guide on consumer units and fuse boxes explains how to tell. The hob installation page covers the worktop cut-out, airflow below the hob and the ratings check in more detail.
Side by side: who is involved and what gets checked
| Gas hob | Induction hob | |
|---|---|---|
| Who connects the supply | A Gas Safe registered engineer qualified for cooking appliances | An electrician or competent installer; a new circuit must be notified or certified under Part P in England |
| Main safety concern | Gas leaks, combustion and carbon monoxide, open flame near materials | Overloading a circuit that was not designed for the hob’s rating |
| Checks after fitting | Leak (tightness) check, gas pressure, burner operation and flame-failure devices | Connection, circuit protection and correct operation of every zone |
| Room requirements | Ventilation and clearances set by the manufacturer | Clearances and airflow under the hob set by the manufacturer |
| When the job grows | No gas pipe at the hob position, a small or unventilated room, a hood or window too close | No cooker circuit, a full consumer unit, an old fuse box |
Changing from one to the other
Gas to induction is the more common switch, and it needs two separate pieces of work. The gas supply to the old hob has to be capped off safely by a Gas Safe registered engineer, and a suitable electrical supply has to be provided where there was previously only a small feed for the ignition. The worktop cut-out is often a different shape too, so it is worth comparing the new hob’s cut-out dimensions before ordering.
Induction or electric to gas depends first on whether there is a gas supply near the kitchen at all. Many homes have gas at the meter but no pipe to the hob position, and some blocks of flats have no gas supply, or have building rules that limit adding one, so check with the managing agent or freeholder before buying. If gas can be run to the hob, check the hood height and the distance to any window or tall unit against the new hob’s instructions, because gas clearances are usually larger.
Questions to settle before you order a hob
- Is there a gas pipe, a cooker circuit, or neither at the position where the hob will go?
- What is the new hob’s maximum rating (on the data plate or in the manual), and is it supplied with a plug or without one?
- Does the cut-out size in the new hob’s instructions match the hole in your worktop?
- For gas, does the kitchen have an openable window, and is the room large enough for the manufacturer’s ventilation requirement?
- What sits above and beside the hob: a cooker hood, a window, curtains, a tall unit?
- If you rent or live in a managed block, has the landlord or managing agent agreed to the change?
If the answers point to induction, or to a like-for-like electric swap, the work is mainly the worktop and the electrics. Voltify Contractors fits induction and ceramic hobs and handles that electrical side, including checking whether a new cooker circuit is needed; any gas connection or capping is carried out separately by a Gas Safe registered engineer. Our hob installation service explains how a fitting is priced and what to send for an accurate answer. If you are weighing up a freestanding cooker instead of a separate hob, our guide to gas and electric cooker installation costs covers that choice.
