What does a house survey actually check?

Key takeaways

• A house survey is a professional inspection that identifies structural flaws, damp, and legal issues.
• The level of detail depends on the survey type, ranging from a basic summary to a deep structural dive.
• Surveyors use a traffic light system to highlight the urgency of required repairs.
• Getting a survey can provide leverage for price negotiations if significant problems are found.

Buying a home is exciting, but it's also one of the biggest financial decisions you'll ever make. While a property may look perfect during a viewing, many problems can remain hidden until after you've collected the keys. That's where a house survey comes in.

A professional house survey gives you an independent assessment of the property's condition before you're legally committed to buying it. Rather than simply confirming the property's value, a survey helps uncover defects, maintenance issues and potential risks that could cost thousands of pounds to repair in the future.

Whether you're purchasing a modern apartment, a Victorian terrace or a countryside cottage, understanding what a house survey checks will help you decide which type of survey you need and why it's such an important part of the home-buying process.

Why is a house survey important?

No property is perfect. Even homes that appear well maintained can hide issues behind freshly painted walls or newly laid flooring. A survey gives you a clearer picture of the property's overall condition before contracts are exchanged. It allows you to budget for future repairs, decide whether further specialist inspections are needed and, in many cases, negotiate a reduction in the purchase price if significant defects are discovered.

If you're still deciding whether you need one, our guide to survey vs mortgage valuation explains why a lender's valuation should never be considered a replacement for a professional survey.

What does a house survey check?

Although the exact scope depends on the type of survey you choose, every RICS survey follows a systematic inspection of the property's visible and accessible elements. The surveyor isn't looking for cosmetic issues like outdated décor or worn carpets. Instead, a house survey checks the visible and accessible parts of a property to identify defects, structural issues, and maintenance needs. It covers everything from the roof and walls to the windows, floors, and drainage systems to ensure safety.

A surveyor acts as your eyes and ears on the ground. They are trained to spot signs of trouble that a typical buyer might miss during a 20-minute viewing.

A survey helps you avoid unexpected costs that average over £5,000 for homebuyers who do not get an independent report. The inspection looks for major issues like subsidence, where the ground under the house moves, and smaller but still costly problems like failing window seals or blocked guttering.

What happens during a house survey on the day?

On the day of the survey, the professional will spend between one and four hours at the property. They will walk through every room, check the exterior, and inspect any outbuildings or boundaries to ensure everything matches the legal description.

The surveyor starts with an external walkaround, checking the roof, walls, and drainage. Inside, they will move from the top of the house down to the bottom. They will open windows, look under sinks for leaks, and check the loft space. It is important to note that surveyors do not move heavy furniture or lift carpet that is tacked down. They are there to observe and report on what is accessible. If they cannot access a certain area, such as a locked garage, they will state this in the final report.

The roof

The roof is one of the first areas a surveyor will assess because repairs can be among the most expensive you'll face as a homeowner. During the inspection, they'll look for missing or slipped tiles, damaged flashing, sagging rooflines, signs of previous repairs, blocked valleys and evidence of water ingress. Where visible, they'll also assess the condition of chimneys and roof coverings.

If loft access is available, the surveyor will inspect the roof structure from inside, checking for daylight through the roof covering, signs of leaks, timber defects and inadequate ventilation.

External walls

External walls can reveal a great deal about the condition of a property. The surveyor will inspect brickwork, render, stonework and cladding for cracks, bulging, movement, weather damage and deteriorating pointing. They'll also assess whether any cracking is cosmetic or indicates structural movement that requires further investigation.

Particular attention is given to older properties where previous repairs or alterations may have affected the building's stability.

Damp and moisture

Damp is one of the most common issues identified during house surveys. Rather than simply looking for mould, surveyors search for evidence of rising damp, penetrating damp and condensation. They may identify staining, peeling wallpaper, salt deposits, damaged plaster or high moisture readings that suggest water is entering the property.

While surveyors don't usually diagnose the exact cause without further investigation, they'll explain the likely issue and recommend whether specialist advice is required.

Windows and doors

Windows and external doors are inspected for their overall condition, operation and signs of deterioration. Surveyors check for rotten timber, damaged frames, failed double glazing, poor seals and evidence of movement that may prevent doors or windows from opening correctly.

Although worn seals or stiff hinges may seem minor, they can sometimes indicate wider structural movement or poor maintenance.

Structural movement

One of the most valuable aspects of a survey is identifying signs of structural movement. Surveyors assess cracks, uneven floors, leaning walls and distorted openings to determine whether movement appears historic, ongoing or potentially serious.

Not every crack indicates subsidence, but recognising the difference requires professional experience. Where movement appears significant, your surveyor will recommend further structural investigation before you proceed.

Floors and ceilings

Inside the property, surveyors inspect floors and ceilings for unevenness, movement, sagging and visible defects. They'll note cracked ceilings, damaged plaster, springy floorboards and signs that may indicate water damage or underlying structural concerns.

Where safe access isn't possible, they'll explain any limitations within the report.

Walls and internal finishes

Internal walls are checked for cracking, damp staining, movement and signs of previous repairs. While surveyors aren't concerned with cosmetic decoration, defects in plasterwork or wall finishes can sometimes reveal more significant problems hidden beneath the surface.

Loft spaces

If accessible, lofts are inspected for insulation, roof structure, ventilation and evidence of leaks. Surveyors also look for timber decay, insect infestation and alterations that may not comply with current building standards.

Chimneys

Where visible, chimneys are checked for leaning stacks, deteriorating mortar, damaged flashing and structural defects. Older chimney stacks can become unstable over time, making this an important part of the inspection.

Gutters and drainage

Rainwater goods play a crucial role in protecting a property from damp. Surveyors inspect gutters, downpipes and drainage where visible, looking for blockages, leaks, poor falls and signs that overflowing water has damaged external walls.

Although underground drainage is rarely tested, any obvious concerns will be highlighted.

Garages, outbuildings and permanent structures

Where included within the property's boundaries, garages and permanent outbuildings are inspected in the same way as the main property. Surveyors assess their condition, structural stability and any obvious maintenance issues that could require attention.

We recommend reading our guide on the 10 common survey problems highlighted in UK properties to help you distinguish between the most concerning repairs.

What is included in a house survey checklist?

A standard survey checklist includes the roof, walls, windows, doors, floors, and ceilings. It also covers the heating system, plumbing, electrical fittings, and the external grounds, including fences, paths, and any signs of invasive plants like Japanese Knotweed.

While the surveyor is not a qualified electrician or plumber, they will perform a visual check of these systems. They will look for outdated fuse boxes or lead piping that might need replacing. They also check the boundaries for any issues that your conveyancer might need to investigate further, such as shared access or encroaching trees.

Pro tip: Always ask your surveyor if they noticed any signs of Japanese Knotweed. This invasive plant can make a property unmortgageable if it is within seven metres of the building, and it requires a professional management plan to resolve.

What doesn't a house survey check?

Although house surveys are comprehensive, there are important limitations.

Surveyors don't move furniture, lift carpets or remove floor coverings. They won't drill into walls or carry out invasive investigations, and they don't test electrical wiring, gas appliances, or plumbing systems as a qualified engineer would.

If visible evidence suggests a problem, the surveyor will usually recommend obtaining a specialist inspection before exchanging contracts.

Similarly, inaccessible areas such as sealed roof voids, locked rooms or heavily obstructed spaces can't be fully inspected. Any limitations will be clearly explained within your survey report.

Does every survey check the same things?

Every RICS survey follows the same fundamental principles, but the depth of inspection varies by survey level. A Level 1 survey provides a broad overview of the property's condition and highlights urgent issues without offering detailed advice on repairs. A Level 2 survey examines the same areas in greater detail and is suitable for most conventional homes. It explains defects, their likely causes and recommended maintenance, making it the most popular choice for buyers. A Level 3 survey offers the most comprehensive inspection available. It explores construction methods, significant defects, potential structural concerns and repair options in much greater depth. This level is generally recommended for older properties, listed buildings, unusual construction types or homes requiring renovation.

If you're unsure which option is right for your purchase, our guide to Level 2 vs Level 3 surveys explains the key differences and when each survey is recommended.

What happens after the survey?

Once the inspection has been completed, you'll receive a written report summarising the surveyor's findings. Most reports use a traffic-light condition rating system, helping you quickly identify which issues require immediate attention and which need monitoring or routine maintenance.

It's important to remember that not every defect should be a cause for concern. Every property has some degree of wear and tear, particularly older homes. Your survey helps distinguish between expected maintenance and more significant issues that could affect your decision to buy.

If major defects are identified, you may wish to discuss the findings with your conveyancer before renegotiating the purchase price or requesting further specialist investigations. Our complete guide to conveyancing explains how survey findings fit into the wider home-buying process and what happens before exchange and completion.

Summary

A house survey is your best defence against buying a money pit. Whether you choose a Level 2 or Level 3 report, the information provided by a RICS professional ensures you can proceed with confidence or renegotiate the price based on facts.

Disclaimer: This article is for informational purposes only. For specific financial or legal advice regarding your property purchase, please consult a qualified financial adviser or solicitor.