How Much Does a Chimney Survey Cost When Selling a House?

Chimneys are one of the most overlooked parts of selling a house. If your property has a working fireplace, a wood-burning stove, or even a chimney that has been blocked up and is no longer in use, it will come under scrutiny during the sale process. The buyer's surveyor will inspect it, the buyer's solicitor will ask questions about it, and any problems that surface at this stage can delay the transaction or knock thousands off your sale price.

This guide explains what a chimney survey involves, how much it costs, when sellers should consider getting one, and how chimney issues can affect your sale. If you are putting together your sale preparation documents, understanding your chimney's condition is an important part of the picture.

What is a chimney survey?

A chimney survey is a professional inspection of your chimney's internal and external condition. Unlike a chimney sweep, which simply cleans the flue, a survey assesses the structural integrity of the chimney stack, the condition of the flue liner, the adequacy of ventilation, and whether the chimney is safe and fit for purpose.

There are three main types of chimney inspection, each offering a different level of detail:

Visual inspection

A visual inspection is the most basic type of chimney survey. The surveyor examines the chimney from ground level and from inside the property, checking the external brickwork, mortar joints, chimney pot, flashing, and the fireplace opening. They look for visible signs of damp, cracking, spalling brickwork, and deterioration. This type of inspection is suitable for properties where the chimney appears to be in reasonable condition and there are no specific concerns. A visual inspection typically costs £100 to £150.

CCTV flue survey

A CCTV survey is the most thorough way to assess the internal condition of a chimney flue. A small camera on a flexible rod is inserted into the flue from the fireplace opening or the chimney pot, and the entire length of the flue is recorded on video. The surveyor can identify cracks in the liner, gaps between liner joints, blockages, areas of deterioration, and whether the flue has a liner at all. This is the recommended survey type for older properties, homes with wood-burning stoves, and any chimney where there are concerns about the flue's condition. A CCTV chimney survey typically costs £150 to £350.

Smoke draw test

A smoke draw test checks whether the flue is functioning correctly by lighting a smoke pellet at the base and observing whether smoke rises cleanly through the flue and exits at the chimney pot. If smoke escapes through cracks, into adjacent flues, or back into the room, the flue has a problem. Smoke tests are often carried out alongside a CCTV survey and cost £50 to £100 as a standalone check.

How much does a chimney survey cost?

Chimney survey costs depend on the type of inspection, the height and accessibility of the chimney, and your location. Here is a breakdown of typical costs in 2026:

Prices are higher in London and the South East, and properties with tall or difficult-to-access chimneys may attract a premium. If you have multiple chimneys, expect to pay for each one separately. For context on how this fits into the overall expense of selling, see our guide on how much it costs to sell a house in 2026.

Chimney sweep vs chimney survey: what is the difference?

Sellers sometimes assume that having the chimney swept is sufficient preparation for a sale. While sweeping is important for maintenance, it is not the same as a survey:

• A chimney sweep removes soot, creosote, bird nests, and debris from the flue. It keeps the chimney safe for regular use and reduces the risk of chimney fires. A sweep does not assess the structural condition of the chimney, the integrity of the liner, or compliance with building regulations.
• A chimney survey is a diagnostic inspection that evaluates the chimney's condition and identifies defects. It produces a written report (and video footage in the case of a CCTV survey) that can be provided to the buyer's solicitor as evidence of the chimney's condition.

If you have a working fireplace or stove, it is good practice to have the chimney swept before the survey. This clears any deposits that could obscure defects during the CCTV inspection, giving you a more accurate picture of the flue's condition.

When should sellers get a chimney survey?

Not every property needs a chimney survey before selling. Here are the situations where it is most advisable:

• You have a wood-burning stove or multi-fuel appliance. These are the most common trigger for chimney-related enquiries during a sale. The buyer's solicitor will want to see evidence that the stove was installed in compliance with building regulations and that the flue is in safe working order.
• You have an open fire that is regularly used. Open fires put more stress on chimney liners than modern stoves, and older flues may have deteriorated over decades of use. A survey provides reassurance.
• The chimney is old and has never been surveyed. Properties built before the 1960s often have unlined flues or original clay liners that may have cracked or deteriorated. A CCTV survey is the only way to know for certain.
• There are visible signs of damp around the chimney breast. Staining on the chimney breast, peeling wallpaper, or a musty smell can indicate damp penetrating through a defective flue or poor weatherproofing at the chimney stack. A survey will identify the source.
• The chimney has been decommissioned or blocked up. Even chimneys no longer in use can cause problems if they have not been properly ventilated and capped. The buyer's surveyor will check this and may raise concerns.
• You are missing HETAS or building control certificates. If a stove was installed without the correct certification, a chimney survey can help establish the current condition of the installation and inform your options for retrospective compliance.

What does a chimney survey check?

A comprehensive chimney survey covers both the internal flue and the external chimney structure. Here is what the surveyor will examine:

Internal flue condition

• Presence and type of flue liner (clay, concrete, stainless steel, or none)
• Cracks, gaps, or deterioration in liner joints
• Blockages from debris, bird nests, or fallen mortar
• Soot and creosote build-up
• Flue diameter and suitability for the connected appliance
• Evidence of previous repairs or patching

External chimney structure

• Condition of the chimney stack brickwork and mortar joints
• Flashing where the chimney meets the roof
• Chimney pot condition and security
• Chimney cowl or cap (if fitted)
• Signs of leaning, cracking, or structural movement
• Weatherproofing and damp-proofing

Fireplace and hearth

• Fireplace opening dimensions and condition
• Hearth size and compliance with regulations
• Throat plate or register plate (for stoves)
• Ventilation provision
• Distance from combustible materials

Chimney liners: what sellers need to know

The flue liner is one of the most important components of a chimney. It protects the chimney structure from heat and corrosive gases, maintains the correct flue diameter for efficient draw, and prevents combustion products from leaking into the property through cracks in the brickwork.

There are several types of chimney liner:

• Clay liners. Found in most properties built from the 1960s onwards. Generally durable but can crack over time, particularly if subjected to rapid temperature changes or if the mortar joints between sections deteriorate.
• Flexible stainless steel liners. The modern standard for relining chimneys. These are inserted into the existing flue and are required for most wood-burning stove installations. They have a lifespan of 15 to 25 years depending on the grade of steel and the type of fuel burned.
• Concrete liners. Found in some post-war and mid-century properties. These can deteriorate and are not suitable for use with wood-burning stoves without relining.
• Unlined flues. Many older properties have no liner at all. The flue is simply the space inside the chimney brickwork. Unlined flues are not suitable for use with modern appliances and present a risk of carbon monoxide leakage and chimney fires.

If a chimney survey reveals that the liner is damaged, missing, or unsuitable for the connected appliance, relining the chimney with a flexible stainless steel liner is the most common solution. This typically costs £800 to £2,000 depending on the chimney height, access, and whether scaffolding is needed.

Decommissioned chimneys and selling

Many properties have chimneys that are no longer in use. The fireplace may have been blocked up, the chimney breast removed on one or more floors, or the chimney pot capped. While a decommissioned chimney does not prevent a sale, it does need to have been dealt with correctly.

Proper decommissioning

A correctly decommissioned chimney should have:

• A ventilation grille fitted in the blocked-up fireplace opening to allow air circulation and prevent condensation build-up inside the flue
• An appropriate cowl or cap on the chimney pot that keeps rain out while allowing ventilation
• No signs of damp staining on the chimney breast, which would indicate inadequate ventilation or failed weatherproofing

Removed chimney breasts

If a chimney breast has been removed on a lower floor but the chimney stack above is still supported, this is a structural matter. The remaining chimney breast on the upper floor and the stack must be properly supported, usually with a gallows bracket or steel beam. This work requires building regulations approval. The buyer's surveyor will check for evidence of proper support, and missing building control sign-off for chimney breast removal is a well-known cause of sale delays. This is one of many hidden costs of selling that can catch sellers by surprise.

HETAS certification and wood-burning stoves

If your property has a wood-burning stove or multi-fuel appliance, HETAS certification is one of the most important documents you need for the sale. HETAS (Heating Equipment Testing and Approval Scheme) is the official body recognised by the UK government for approving solid fuel heating appliances and registering competent installers.

What HETAS registration means

A HETAS registered installer is qualified to install solid fuel appliances, flue systems, and associated hearth and ventilation requirements in compliance with Building Regulations Approved Document J. Installations carried out by HETAS registered installers are self-certified, meaning the installer can sign off the work without a separate building control inspection. The installation is automatically notified to the local authority.

What happens if you do not have a HETAS certificate

If your wood-burning stove was installed without HETAS certification or building control sign-off, the buyer's solicitor will flag this as a compliance issue. Your options include:

• Retrospective building control approval. You can apply to your local authority for a regularisation certificate. A building control officer will inspect the installation and, if it meets current standards, issue a certificate. This typically costs £250 to £500 and can take several weeks.
• Indemnity insurance. If retrospective approval is not practical, your solicitor may suggest taking out an indemnity insurance policy to cover the buyer against the risk of enforcement action. This is a one-off cost of around £100 to £300. However, not all buyers or their lenders will accept indemnity insurance as a substitute for proper certification.
• HETAS survey and report. A HETAS registered engineer can inspect the existing installation and provide a report on its compliance. While this is not the same as a certificate of compliant installation, it provides evidence that the installation has been assessed by a competent person.

For a full overview of what your solicitor will need, see our guide on the TA6 services section.

Building regulations for chimney and stove installations

In England and Wales, the installation of solid fuel appliances is governed by Building Regulations Approved Document J (Combustion Appliances and Fuel Storage Systems). Key requirements include:

• The flue must be the correct diameter for the appliance and must extend at least one metre above the highest point of the roof where it passes through
• The hearth must be a minimum of 840mm x 840mm and at least 12mm thick, made from a non-combustible material
• Combustible materials must be kept at specified distances from the stove and flue pipe
• Adequate ventilation must be provided to the room where the appliance is installed, typically via a permanent air vent
• A carbon monoxide alarm must be fitted in the same room as the appliance (mandatory since October 2010 for new installations)
• In smoke control areas, the appliance must be DEFRA-exempt or burn an authorised smokeless fuel

Non-compliant installations are a red flag for buyers and their solicitors. If you know or suspect that your stove installation does not meet these requirements, address the issue before listing your property.

How chimney issues affect a house sale

Chimney problems can impact your sale in several ways, depending on their severity and when they are discovered:

During the buyer's survey

The buyer's surveyor will inspect the chimney as part of a homebuyer's report or building survey. Common issues they flag include deteriorating mortar joints, damp around the chimney breast, a leaning chimney stack, missing or defective flashing, and the absence of a chimney cowl. If the surveyor recommends a specialist chimney inspection, the buyer may request that you arrange one at your expense, or they may arrange their own and use the findings to renegotiate the price.

During conveyancing enquiries

The buyer's solicitor will ask about heating appliances, fireplaces, and any work carried out on the chimney as part of the standard conveyancing enquiries. They will want to see HETAS certificates, building control sign-off, chimney sweep records, and any survey reports. If documentation is missing, they will raise further enquiries, which can add weeks to the timeline.

Mortgage lender conditions

If the buyer's surveyor flags significant chimney defects, the mortgage lender may impose a retention on part of the mortgage funds until the issue is resolved. This means the buyer cannot access the full amount they need to complete the purchase until the chimney problem is fixed or independently assessed as acceptable. This can delay completion and, in some cases, cause the sale to fall through entirely.

What to disclose about your chimney on the TA6

The TA6 Property Information Form requires you to disclose information about your property's services, heating, and any alterations or works carried out. When it comes to chimneys, you should disclose:

• Whether the property has working fireplaces or stoves, and which fuels they burn
• When the chimney was last swept and by whom
• Any chimney surveys or inspections that have been carried out, along with copies of the reports
• Whether any stove or fireplace was installed during your ownership, and whether HETAS certification or building control sign-off was obtained
• Any chimney repairs or alterations, such as relining, repointing, or chimney breast removal
• Any known defects, such as damp on the chimney breast, smoking back into the room, or a failed smoke test
• Whether any chimneys have been decommissioned and how this was done

Honest and thorough disclosure protects you from potential claims after completion. If you are unsure about what to disclose, your solicitor can advise. For guidance on the full range of certificates and documentation you may need, see our guide on gas safety certificates when selling, which covers a similar area.

Seller's checklist for chimney preparation

Use this checklist to make sure your chimney does not become a sticking point during the sale:

1. Have the chimney swept by a NACS-registered or HETAS-approved sweep before listing
2. If you have a wood-burning stove, locate your HETAS certificate or building control sign-off and provide a copy to your solicitor
3. Consider a CCTV chimney survey if the chimney is old, has never been inspected, or shows signs of damp
4. If the chimney has been decommissioned, check that it has been properly ventilated and capped
5. If a chimney breast has been removed, confirm that building control approval was obtained and that the remaining structure is properly supported
6. Ensure a carbon monoxide alarm is fitted in any room with a solid fuel appliance
7. Complete the relevant sections of the TA6 form accurately and attach any certificates, survey reports, and sweep records
8. Address any defects identified by the survey before listing, or be prepared to disclose them and negotiate on price

Sources

• HETAS (Heating Equipment Testing and Approval Scheme) — hetas.co.uk
• National Association of Chimney Sweeps (NACS) — nacs.org.uk
• Building Regulations Approved Document J: Combustion Appliances and Fuel Storage Systems — GOV.UK
• The Building Regulations 2010 (as amended) — legislation.gov.uk
• Law Society — Property Information Form (TA6), 4th edition
• RICS Home Survey Standard — rics.org

Frequently asked questions