Safety first — call this first by situation

Smell gas, hear hissing or suspect a gas leak. Do not switch anything on or off, and do not use flames, electrical appliances, or smoke. Leave the property if the smell is strong, then call the gas emergency service on 0800 111 999 (free, 24/7) from outside. Open doors and windows if it is safe to do so. If you know where the gas meter control valve is and can reach it safely, turn off the gas supply at the meter.¹

Carbon monoxide symptoms — headaches, dizziness, nausea, breathlessness, collapse. Get everyone outside into fresh air immediately. If safe to do so, switch off the suspected appliance and — if you know where the gas meter control valve is — turn off the gas supply at the meter. Open doors and windows on your way out. Call 999 if anyone has collapsed or is seriously unwell, or 111 for non-emergency medical advice. Then call 0800 111 999. Do not re-enter the property until told it’s safe. See GOV.UK CO guidance.¹⁷

Active leak from a boiler or heating circuit. Turn off the boiler at the fused spur if safe. Do not touch gas components. If water is escaping, use the internal stop tap or call an engineer. See Burst Pipes Lambeth for active flooding from a fresh-water pipe.

Water reaching electrics around the boiler. Do not touch electrical systems if water is present. Only isolate power at the consumer unit if it is safe to access without contact with water.

Right page for your problem?

This page is for boiler installation — new and replacement boilers, conversions, relocations, system upgrades. For other situations:

• Boiler not heating, error code, intermittent fault → Boiler Repair Lambeth (diagnostic-first; often cheaper than replacement)
• Annual service or landlord gas safety check → Boiler Servicing Lambeth
• Heating system not heating the whole property → Central Heating Repair Lambeth
• Active emergency, water escaping → Emergency Plumber Lambeth or Burst Pipes Lambeth
• Active gas leak → call 0800 111 999¹

Repair vs replace?

A boiler that’s broken doesn’t always need replacing. Diagnostic-first is normally the cheaper route.

Lean towards repair if:

• Boiler is under ~10 years old
• Fault is a single component (PCB, pump, diverter valve, thermostat)
• Spare parts are available from the manufacturer
• Annual service has been kept up

Lean towards replacement if:

• Boiler is 12–15+ years old (typical industry lifespan; efficiency may be materially below current standards)
• Multiple components have failed in the past 2 years
• Spare parts are obsolete or expensive
• Heating bills have risen significantly

For a diagnostic-first approach see Boiler Repair Lambeth. The decision often comes down to age, repair cost as a percentage of replacement cost, and how much disruption you can tolerate from another mid-winter breakdown.

Boiler Plus 2018 — what applies to a new install

Per the GOV.UK Boiler Plus factsheet, all new and replacement gas boilers installed in England since April 2018 must:¹⁹

• Have a minimum space heating efficiency of 92% ErP
• Include time and temperature controls (a programmer and room thermostat) — required for all gas and oil boiler installations if not already present

In addition, every new combi boiler install must include one of these four energy efficiency measures:

• Weather compensation — boiler adjusts flow temperature based on outside temperature via a sensor
• Load compensation — boiler adjusts flow temperature based on how the room is heating
• Flue Gas Heat Recovery (FGHR) — a device that recycles heat from flue gases to preheat hot water
• Smart controls — only smart controls with automation and optimisation functions meet Boiler Plus requirements; basic app-controlled thermostats alone do not. Smart controls with load or weather compensation also satisfy the requirement.

Your Gas Safe engineer should advise which of the four is most cost-effective for your property and lifestyle.

A non-compliant install is a Building Regulations breach. Per Gas Safe Register, your engineer should notify the local authority through Gas Safe Register within 30 calendar days. Once notified, the Building Regulations Compliance Certificate is usually issued within 10–15 working days after notification.⁴⁶

What’s involved in a boiler install

A typical like-for-like boiler replacement is 1–2 days. Significant work — system to combi conversion, relocation to a new room, full system upgrade — can take 3–5 days or longer.

A reputable installer will:

• Survey the property (existing boiler, gas supply, flue route, system condition, hot water demand, radiator sizing)
• Provide a written, fixed-price quote covering boiler, controls, parts, labour, system flush, and certification
• Confirm warranty (manufacturer’s warranty is normally tied to annual servicing being kept up)
• Power-flush or chemical-clean the system if needed (older systems with sludge often require cleaning)
• Install the boiler and any new controls (programmer, thermostat, smart control if specified)
• Fit a magnetic system filter (commonly recommended on most installs to protect the new boiler from sludge)
• Commission and test the system
• Provide a Benchmark commissioning checklist, Building Regulations Compliance Certificate, and Gas Safe registration

If system cleaning isn’t included in the quote and the existing system is silted up, manufacturer guidance may require system cleaning at install (power flush or chemical clean depending on system condition) for warranty purposes. Confirm this with the installer.

When you call

Before the engineer surveys or quotes:

• Existing setup — boiler make/model and approximate age (often on a sticker on the boiler casing), fuel type, location
• Heating and hot water needs — how many bathrooms, how many people, simultaneous hot water demand (e.g. two showers at once)
• Type preference — combi (no cylinder, hot water on demand), system (separate cylinder, mains-pressure hot water), regular (cylinder + cold water tank in loft)
• Relocation — moving the boiler often requires re-routing gas, flue, condensate drain and pipework. Significantly more expensive.
• Multiple quotes — for a major spend, get at least 2–3 written quotes. Confirm what’s included (system flush, magnetic filter, controls) — quotes vary widely on inclusions.
• Finance options — many installers offer manufacturer-backed finance. Compare the total cost including interest.

Have ready when you call: existing boiler make/model and approximate age, fuel (gas / LPG), boiler type (combi / system / regular), property type and size, hot water and heating preferences, whether you want to relocate the boiler, and your postcode.

Note on oil boilers: This page is primarily for gas and LPG boiler installation. For oil-fired boilers, confirm the installer holds the appropriate oil-heating competence (OFTEC registration is the common scheme); Gas Safe registration does not cover oil-boiler competence.

Boiler types — quick guide

• Combi (combination) boiler — heats water on demand, no cylinder, no cold water tank. Compact, suits flats and smaller homes. Limited simultaneous hot water (e.g. running two showers strains a combi).
• System boiler — works with a hot water cylinder. Mains-pressure hot water, good for properties with multiple bathrooms. Cylinder takes space.
• Regular (heat-only) boiler — works with a cylinder and a cold water tank in the loft. Common in older Lambeth properties; conversion to combi or system is a common renovation upgrade.

Conversion (regular to combi, or regular to system) is a more involved job than like-for-like replacement — significantly more pipework, possibly removing a tank or cylinder, and rebalancing the heating.

Lambeth-specific signals

Conversion flats and combi compatibility

Victorian and Edwardian conversion flats are common across Brixton, Clapham, Stockwell, Herne Hill, Tulse Hill, Streatham and West Norwood. In conversion flats, combi boilers are the most common choice — compact, no cylinder needed.

But mains water pressure can vary significantly between flats in the same building, especially when several flats draw at once. A combi’s hot water performance depends heavily on incoming mains pressure. The installer should test at the kitchen tap before specifying the boiler — an undersized combi in a low-pressure flat will struggle.

Regular-to-combi conversions in older properties

Older Lambeth properties — particularly in Kennington, Stockwell, Herne Hill, Tulse Hill and West Norwood — were originally fitted with regular boilers, hot water cylinders in airing cupboards, and cold water tanks in the loft. Conversion to combi is a common renovation, but the existing pipework and radiator layout may need rebalancing, and removal of the cylinder and loft tank changes the property’s space planning. Discuss the full implications at survey.

Flue routing and conservation areas

Per Lambeth Council, the borough has 62 designated conservation areas covering approximately 30% of its area.⁸

Flue routing on a front elevation, on a visible side return, or near a listed feature may need consideration in a conservation area. Rear flues are usually unproblematic. Lambeth Council administers these as the local planning authority. Discuss with the installer if the proposed flue position is on a visible elevation.

Listed buildings

Some Lambeth properties are listed. Listed building consent may be required for substantial alterations including new flue terminals, condensate drains, or boiler relocations that affect external elevations. Check Lambeth Council planning guidance before commissioning major works.

Hard water

Lambeth sits in Thames Water’s hard-water area.²⁶ Hard water can contribute to limescale build-up on heat exchangers and shower elements over time. Many installers recommend a scale inhibitor or in-line scale reducer at install — discuss with the engineer. A magnetic system filter (Magnaclean or equivalent) is a separate device that catches iron oxide / sludge from the heating circuit; both are commonly fitted at install.

Lambeth council tenants and leaseholders

Per Lambeth Council’s repair responsibility guidance, the Council is responsible for the boiler and heating system in council-owned homes — subject to tenant responsibilities, misuse exclusions, and whether the appliance was provided or authorised by the Council.⁹

If you’re a Lambeth council tenant:

• Working day repair: 020 7926 6000, or via your online tenant account.¹⁰
• Out-of-hours emergency repairs: 020 7926 6666 — for issues classified as emergencies by Lambeth Council, such as no heating in cold weather, suspected gas leak, or no hot water with vulnerable occupants.³ ¹⁰

Council tenants cannot normally arrange their own boiler installation. The Council has its own programme of replacements based on age, condition, and resident need.

If you book a private installer instead of going through the Council, you may not be reimbursed unless the work was authorised or Lambeth policy allows it.

Leaseholders of former council flats: the boiler and pipework inside your demised premises is typically your responsibility under the lease, per Lambeth’s leaseholder repair guidance.¹² Communal heating systems (district heating, communal boilers serving a block) are usually the freeholder’s. Always refer to your individual lease, which overrides general guidance.

Private renters and landlords

Per Section 11 of the Landlord and Tenant Act 1985, every short-lease residential tenancy contains an implied covenant by the landlord to keep in repair and proper working order the installations for the supply of water, gas, electricity and sanitation, and for space heating and water heating.¹³ A failed boiler in a rented home is likely to engage Section 11 repair duties, for tenancies covered by Section 11. Tenants may be liable where damage is caused by misuse.

Tell the landlord (or letting agent) in writing as soon as possible. Lack of heating or hot water in cold weather is a serious matter — keep a copy of any messages.

If the landlord won’t act, contact Lambeth Private Sector Housing where licensing or housing-condition enforcement applies.

Per HSE, landlords must arrange an annual gas safety check by a Gas Safe registered engineer, keep records for 2 years, and issue a copy of the Landlord Gas Safety Record (often called a CP12) to tenants within 28 days of the check.¹⁸

Selective licensing

Lambeth’s Selective Licensing Scheme currently applies to many privately rented homes in the borough — typically those let to a single-family household or no more than two unrelated sharers — across most wards, with Vauxhall and Waterloo & South Bank excluded.¹⁴ Coverage is subject to ward designation, property-level exemptions, and change.

Check current status with Lambeth Council before relying on this — designations are time-limited. HMOs continue to be licensed separately under the Council’s HMO licensing schemes. A licensed landlord must keep the property in good repair as a licence condition.

What does a boiler installation cost in Lambeth?

For boiler installation, most quotes are fixed-price after a survey. You should be told the full price (boiler, controls, parts, labour, flush, certification) before work begins. For multiple quotes, confirm exactly what’s included in each — quotes vary widely on what’s bundled vs charged separately.

Indicative directory estimates only, based on London boiler installation market familiarity — not regulated rates and not official market data. No official pricing data exists for private boiler installation.

Always confirm pricing before work begins. Actual costs vary by boiler choice, property, scope, access, and time. VAT applies. Boiler supply (indicative directory range, before fitting): budget brands from around £700, mid-range £900–£1,500, premium £1,500–£2,500+. Manufacturer pricing varies and is set by the supplier — confirm the exact boiler price with your installer.

A reputable quote should bundle the boiler, controls, system flush (if needed), magnetic filter, and certification. A bare-bones quote that excludes flush and filter may compromise the manufacturer warranty.

Lambeth-specific cost factors:

• Conversion flat low-pressure mains — combi boiler choice in low-pressure conversion flats may need a higher-spec model with internal pressure boost, which adds cost. The installer should test before specifying.
• Regular-to-combi conversions in older properties — full conversion in Kennington, Stockwell, Herne Hill, Tulse Hill or West Norwood properties with original tank and cylinder layouts brings cylinder removal, loft tank removal, pipework reconfiguration and radiator rebalancing into scope.
• Flue routing in conservation areas — front-elevation or visible side-return flue routing in any of Lambeth’s 62 conservation areas may need planning consideration, adding lead time.
• Listed building consent — substantial alterations affecting external elevations may need listed building consent before work starts.
• Conversion flat freeholder consent — boiler relocation that affects shared services or visible elevations in a conversion flat normally needs freeholder/managing-agent consent.
• Council-owned homes — council tenants cannot normally arrange private installations; the Council has its own replacement programme. Leaseholders pay for their own boiler work.

Why directory-listed Gas Safe plumbers

Boiler installation is gas work — Gas Safe registration is a legal requirement. Under the Gas Safety (Installation and Use) Regulations 1998 (enforced by HSE), any gas work on a domestic gas appliance must be carried out by a Gas Safe registered engineer competent for that category of work, with registration through the Gas Safe Register. Always check the current Gas Safe ID card before any work begins — per HSE, the card has the engineer’s photo, licence number, and the categories of work they’re qualified for.⁵ ¹⁵

Before any engineer appears in this directory we check, at minimum:

• Gas Safe registration for any engineer offering gas work, against the Gas Safe Register’s check an engineer service.⁵
• Public liability insurance — industry-standard rather than a legal requirement, but every listing carries it at time of listing.
• Business identity — registered company details, trading name, and trading address.

Listing checks are completed before publication and repeated annually. Gas Safe status should still be checked again at booking.⁵

FAQs – Boiler Installation in Lambeth

Areas covered

• SW2 — Brixton, Brixton Hill, Streatham Hill (parts)
• SW4 — Clapham, Clapham Common, Clapham Park (parts)
• SW8 — South Lambeth, Stockwell (parts), Vauxhall (parts), Oval (parts)
• SW9 — Brixton (parts), Stockwell (parts), Angell Town, Loughborough Junction (parts), Oval (parts)
• SW12 — Clapham Park (parts) (postcode crosses borough boundary)
• SW16 — Streatham, Streatham Hill (parts), Streatham Vale
• SE1 — Waterloo, South Bank, Lambeth (North Lambeth) (parts), Vauxhall (parts)
• SE5 — Brixton (parts), Myatt’s Fields
• SE11 — Kennington, Vauxhall (parts), Oval (parts)
• SE19 — Crystal Palace (parts), Gipsy Hill (parts)
• SE21 — Tulse Hill (parts), West Dulwich
• SE24 — Herne Hill, Tulse Hill (parts), Loughborough Junction (parts)
• SE27 — West Norwood, Tulse Hill (parts), Gipsy Hill (parts)

Related services in Lambeth

• Boiler Repair Lambeth
• Boiler Servicing Lambeth
• Central Heating Repair Lambeth
• Emergency Plumber Lambeth
• General Plumbing Lambeth

Related guides

• Should I Repair or Replace My Boiler?
• London Plumbing Costs & Compliance Guide 2026
• How to Read a Plumbing Quote
• New Homeowner Plumbing Guide — London 2026

Closing

A boiler installation is one of the larger plumbing investments in a property’s lifecycle. Get at least two written quotes, check what’s included (system flush, magnetic filter, controls, certification), confirm the engineer is Gas Safe registered, and verify the manufacturer warranty terms before committing.

Boiler Plus 2018 compliance is mandatory for new gas boiler installs in England — your engineer should explain which combi efficiency measure they’re including and provide Building Regulations Compliance Certification on completion.

For Lambeth landlords, keeping installations for space heating and water heating in repair and proper working order is a Section 11 duty under the Landlord and Tenant Act 1985, for tenancies covered by Section 11.¹³ Lambeth’s Selective Licensing Scheme currently applies to many privately rented homes across the borough except in Vauxhall and Waterloo & South Bank wards — check current status with Lambeth Council before relying on this.

Contact directory-listed Gas Safe engineers in Lambeth ↑

← Back to all plumbing services in Lambeth

Last reviewed: May 2026 by Adiel Khan — SFEDI-accredited business advisor with 20+ years experience (South East Enterprise Ltd) and operator of VerifiedPlumbers. LinkedIn ↗

This page is reviewed against guidance published by HSE ↗, Gas Safe Register ↗, GOV.UK legislation ↗, Thames Water ↗ and London Borough of Lambeth ↗. Source links are provided within this page where relevant.

Sources & further reading

¹ HSE — Domestic gas safety FAQ (gas emergency contact). https://www.hse.gov.uk/gas/domestic/faqs.htm ³ Lambeth Council — Emergency contact numbers. https://www.lambeth.gov.uk/about-council/contact-us/emergency-contact-numbers ⁵ Gas Safe Register — Check An Engineer. https://www.gassaferegister.co.uk/find-an-engineer-or-check-the-register/check-an-engineer/ ⁸ Lambeth Council — Conservation area profiles. https://www.lambeth.gov.uk/planning-and-building-control/conservation-and-listed-buildings/conservation-area-profiles ⁹ Lambeth Council — Our repair responsibility. https://www.lambeth.gov.uk/housing/housing-repairs/tenants-repairs/our-repair-responsibility ¹⁰ Lambeth Council — Request a housing repair. https://www.lambeth.gov.uk/housing/housing-repairs/tenants-repairs/request-housing-repair ¹² Lambeth Council — Leaseholders and repairs. https://www.lambeth.gov.uk/housing/housing-repairs/leaseholders-repairs ¹³ Landlord and Tenant Act 1985, Section 11 — legislation.gov.uk. https://www.legislation.gov.uk/ukpga/1985/70/section/11 ¹⁴ Lambeth Council — Selective Licensing Scheme. https://www.lambeth.gov.uk/housing/landlords-licensing/selective-licensing-scheme ¹⁵ HSE — Check an engineer – are they Gas Safe registered? https://www.hse.gov.uk/gas/gas-safe-register-check.htm ¹⁷ GOV.UK — Carbon Monoxide: Be Alarmed. https://www.gov.uk/government/publications/carbon-monoxide-be-alarmed/carbon-monoxide-be-alarmed-fact-sheet ¹⁸ HSE — Gas safety records. https://www.hse.gov.uk/gas/landlords/gassaferecord.htm ¹⁹ GOV.UK — Boiler Plus 2018 factsheet (BEIS). https://assets.publishing.service.gov.uk/media/5b2cc1e2ed915d586e2d8fe9/Boiler_Plus_Factsheet_v3.pdf ²⁶ Thames Water — Hard water. https://www.thameswater.co.uk/help/water-and-waste-help/water-quality/hard-water ⁴⁶ Gas Safe Register — Building Regulations certificates. https://www.gassaferegister.co.uk/gas-safety/gas-safety-certificates-records/building-regulations-certificate/