Boilers
The boiler in your tenement flat
A boiler in a tenement flat normally belongs to the flat it heats, and every job on it, from the yearly service to a full replacement, must be done by a Gas Safe registered engineer.
By the Pipes Up the Stair site team · how pages are checked · Updated
Many tenement flats have their own gas boiler, often squeezed into a kitchen press or a hall cupboard, with a flue through an outside wall. It sits in a shared building, but day to day it is the flat's own business.
This page covers who answers for it, who may touch it and the rules that apply when it is serviced or replaced.
Who is responsible for the boiler in a tenement flat?
Usually the owner of the flat it serves. The Tenements (Scotland) Act 2004 says that a part such as a pipe or flue that wholly serves one flat belongs to that flat, while one serving two or more flats is shared by the flats it serves. Title deeds come first, so check yours. HSE also reminds landlords that any communal gas appliances, flues and pipework their tenants use must be maintained and checked.
Who is allowed to work on it?
Only a Gas Safe registered engineer who is competent for that kind of work. HSE says anyone employed on gas appliances in homes must be registered, and the licence number from the ID card lets you check them. That check is set out step by step in hiring a plumber or gas engineer. Householders should never open the casing, adjust the burner or touch the flue.
How often should it be serviced?
Once a year. HSE advises that gas appliances, flues and pipework be serviced at least annually by a Gas Safe registered engineer, and SGN gives the same advice. For landlords, HSE adds that a service and a gas safety check are not the same thing, so one should not be assumed to include the other.
What should the pressure gauge show?
Between roughly 1 and 1.5 bar with the heating off, according to Ideal and Vaillant; your own manual has the final word. A drop after bleeding radiators is normal. Topping up is only for boilers with clearly marked filling controls, as our radiators page explains; anything else goes to your engineer.
Does replacing a boiler need a building warrant?
It depends on the job, so ask the council's building standards service before work starts. Schedule 3 of the Building (Scotland) Regulations 2004 lists work that needs no warrant but must still meet the standards. Its like-for-like replacement entry, type 24, excludes any oil firing or gas fired boiler. Type 6 covers work on a combustion appliance installation but excludes gas appliances over 70 kW net input and any work associated with a chimney, flue pipe or constructional hearth; type 7 covers a balanced flue serving a room-sealed appliance.
What if the building is listed or in a conservation area?
Check with the City of Edinburgh Council before a new flue goes through a wall. Listed building consent is needed for work affecting a listed building's character, and the council decides what counts. Our page on listed buildings and conservation areas has more.
What about an unvented hot water cylinder?
It needs a properly trained installer and a yearly check. Scotland's domestic Technical Handbook (the 2022 version) says installation should be by a person with appropriate training and practical experience, with labelling that identifies the installer. Cylinder maker Gledhill advises an annual check of the safety devices by a qualified engineer.
Does the boiler room need a carbon monoxide alarm?
Yes. A gas boiler is a fixed combustion appliance, so under Scotland's tolerable standard its room needs a CO detector. See our gas smell and carbon monoxide page for what to do if it sounds.
| Type | What the schedule covers | What it leaves out |
|---|---|---|
| 6 | Work on a fixed combustion appliance installation | Gas appliances over 70 kW net input; chimney, flue pipe or hearth work |
| 7 | A balanced flue serving a room-sealed appliance | - |
| 8 | Pipework, radiators and controls for type 6 work | - |
| 24 | Like-for-like replacement | Any oil firing or gas fired boiler |
Asked on the stair
Is the flue on the outside wall shared with the other flats?
Not if it serves only your boiler. Under section 3 of the Tenements Act a flue that wholly serves one flat goes with that flat, unless your title deeds say otherwise.
Does the landlord's gas safety record have to be kept?
Yes. HSE says landlords must keep the record for 2 years and give each existing tenant a copy within 28 days of the check.
Can a landlord's check be done early without losing the date?
HSE says the check can be done up to 2 months before it is due while keeping the original deadline.
Who services the cylinder if the boiler engineer won't?
Gledhill advises contacting the engineer who installed the cylinder and giving the make and model in advance.
Where this comes from
- Tenements (Scotland) Act 2004, section 3 — parts serving one flat or several
- HSE: Gas safety FAQs — Gas Safe registration, ID card, yearly servicing
- HSE: Landlords FAQs — communal appliances, service versus safety check
- HSE: Gas safety record — record kept and copied to tenants
- Building (Scotland) Regulations 2004, schedule 3 — types 6, 7 and 24
- Technical Handbook 2022, 4.9 Danger from heat — unvented cylinder installers
- Gledhill: Unvented cylinder safety — annual check
- HSE: Why and where asbestos — buildings before 2000
- HSE: Asbestos diagrams — board around boilers