FAQs & Common Defects

The Roof

The roof plays a critical role in protecting the building beneath. Structural issues or defects can quickly affect other areas of the property.

Roof structures come in different forms, designed to transfer the load of the roof coverings to the external walls. Older properties, particularly those from the 19th century and earlier, may have design deficiencies that influence the type of survey recommended.

Alterations or inappropriate replacement of roof coverings can weaken overall performance. Moisture penetration is a particular concern, making regular maintenance vital. This includes attention to roof coverings, flashings and rainwater goods such as gutters.

During a building survey, both the internal and external aspects of the roof are assessed where accessible. Identifying issues with the roof is one of the key reasons buyers commission a full Homebuyer Report or Building Survey before purchase.

Rainwater Goods

Poor rainwater disposal is one of the most common causes of damp in properties, especially older buildings with outdated systems.

Modern gutters and downpipes are usually made from PVC, but many older properties still rely on iron systems that are prone to corrosion and failure. These often need repair or replacement due to years of neglect.

If rainwater goods are blocked or too small to manage the volume of water from the roof, water can overflow. This leads to saturated brickwork and internal damp, particularly in solid masonry walls. Over time, this also causes defects such as frost damage and spalling.

Valley gutters, which run between roof slopes, are especially vulnerable and may not be accessible during a routine survey. Damp from these areas can penetrate internally. Where possible, the underside of the valley is checked from within the roof space.

Regular maintenance of rainwater systems is essential to avoid costly long-term repairs and protect the building’s fabric.

Main Walls

Main walls support the structure of a building and protect it from external elements. They can be constructed in a variety of ways depending on the age and type of property.

Walls are generally classified as either framed or mass. Framed walls use internal supports such as studs or posts to carry loads, while mass walls are solid and include materials such as brick, concrete, stone, cob or earth.

These walls also play a role in controlling moisture. Some absorb and release it through evaporation, while others use external finishes or cladding to deflect moisture. In newer constructions, insulation is often integrated into both wall types to improve efficiency.

Party walls, which separate attached properties, are designed to resist fire, sound and unauthorised access. Internal partition walls may or may not be load-bearing and are typically built using different methods depending on the construction era.

Ongoing maintenance of both external and internal walls is essential. Poor upkeep can lead to water penetration, fabric deterioration and structural movement.

Windows and Doors

Windows and doors are assessed during surveys for condition, design, glazing type and compliance with safety standards.

These elements are made from a range of materials including timber, aluminium, steel and uPVC. Their design and condition can significantly affect the energy efficiency, safety and appearance of the property.

Common window types include fixed or opening casements, single and double-hung sash, tilt-and-turn, pivot, and sliding designs. Some roof structures also incorporate skylights, vents or lantern windows. Bay windows are frequently found in properties built from the Victorian period through to the 1930s.

During a survey, we consider means of escape in case of emergency and check for the presence of safety glazing, particularly in locations where glass could be a hazard, such as near ground level or within doors. Modern glazing should meet toughened or laminated standards.

Many window and door issues stem from poor installation or lack of maintenance. Repairs or replacements can be expensive, so their condition is an important part of the survey process.

Interior of the Property

A full internal inspection is carried out to assess the building’s overall condition, materials and finishes.

The inspection covers all accessible areas including wall, ceiling and floor surfaces, internal fittings and fixtures, visible services and sanitary ware. The roof void is inspected where possible to support findings from within the main living areas.

The survey report outlines the materials present, their condition and any recommended remedial works or replacements identified at the time of inspection.

Floors

Floors are inspected for structure, ventilation, and signs of damage, particularly in older or suspended systems.

Floors typically consist of a sub-floor and covering, with electrical wiring, plumbing or other services often built in. Ground floor construction may be solid or suspended on joists, depending on the property’s design.

Suspended floors require sub-floor ventilation to prevent damp and infestation. First floor structures, usually lighter in design, are supported by internal and external walls.

Surveyors assess any visible or suspected issues that may compromise the floor’s condition or load-bearing integrity.

Services within Buildings

Surveyors carry out a visual inspection of building services, with recommendations for further checks where needed.

While most RICS-regulated surveyors are not qualified engineers or technicians, they will observe the condition of visible services such as electrics, plumbing, heating and drainage as part of the survey process. Where defects or concerns are noted, you may be advised to commission further specialist investigations.

This may apply where services appear poorly maintained, are of an older specification, or show signs that upgrading or renewal may soon be necessary. Specialist reports can confirm condition, safety compliance and cost of remedial works.

Because servicing and system replacement can carry significant costs, a surveyor’s advice on further checks should be followed up before committing to a purchase.

The Site and Environmental Influences

External environmental factors may influence both your comfort and the long-term value of a property.

The site itself, along with its immediate surroundings, is assessed as part of the survey. Surveyors look for anything that could affect the marketability of the property or impact your enjoyment of it. This includes things like nearby sources of noise, odour, or heavy traffic, as well as structural concerns such as signs of subsidence or flood risk.

Environmental risks such as radon gas are also considered, with desktop research carried out prior to the inspection. These elements are not always visible, but if your surveyor identifies concerns, further investigation may be recommended.

Whether it’s a nearby railway line, industrial site or something less obvious, your report will flag any known or suspected issues that may influence your decision to proceed with a purchase.

Asbestos

Asbestos is still commonly found in properties built or refurbished between the 1950s and 1980s.

Asbestos is a naturally occurring mineral that was widely used in domestic construction due to its fire resistance and insulation properties. It is found in various materials such as ceiling coatings, pipe insulation, roofing sheets, and floor tiles.

Its use was largely phased out after serious health risks became known. Inhaling asbestos fibres can lead to long-term lung conditions, including mesothelioma and asbestosis. The supply of certain asbestos types was banned under the Asbestos Prohibition Regulations 1985.

Identifying asbestos by sight alone is not always possible, and testing by a certified laboratory is required for confirmation. If surveyors suspect that a component contains asbestos, they will advise caution and note its condition.

Where materials are in good condition, it is often safer to leave them undisturbed. However, damaged or deteriorating materials require attention from a qualified professional. A surveyor will highlight potential asbestos-related risks and advise on next steps, especially for properties dating from the mid-20th century.

Rising Dampness

Rising damp is a common and visible issue in older properties, often signalled by damaged walls and woodwork.

This problem occurs when moisture from saturated ground rises through porous masonry due to the absence or failure of a damp-proof course (DPC). Signs include blistering paint, deteriorated skirting boards, and a visible tidemark on internal walls.

The requirement for a DPC was introduced in the Public Health Act 1885. Many older properties were built without one, and in others, existing DPCs may have failed due to age, ground movement, or bridging from debris or render.

Modern remedial solutions include the installation of a new chemical DPC or, where appropriate, a physical barrier. In some traditional buildings, these interventions must be carefully considered to avoid causing further complications.

Rot and Infestation within Buildings

Rot and timber infestation can significantly weaken a building’s structure if not identified and managed early.

Rot may affect internal or external joinery, often due to prolonged damp exposure or lack of maintenance. On the exterior, failed paintwork, blocked gutters, or poor detailing can all contribute to decay. Surveyors check for these signs and advise on appropriate remedial actions.

Damp conditions can also lead to beetle infestations, especially in structural timbers such as roof joists or floorboards. If left untreated, infestations and rot can make timbers brittle and structurally unsound.

Dry rot is less common than it once was, but where it occurs, it can spread quickly—even behind plaster and through masonry. Wet rot is typically caused by prolonged damp and is often found in hidden areas such as floor voids or near defective roof coverings.

Wood-boring insects (commonly called woodworm) thrive in damp environments. Where ventilation is poor or moisture levels are high, conditions become ideal for infestation. Treatment may involve both repair and specialist intervention.

A surveyor may recommend further inspection by a timber specialist if there is any doubt, particularly where hidden timbers are involved or signs of infestation are noted during the survey.

Non-traditional/System Built Houses

Post-war housing systems were designed to meet urgent demand, but some now present challenges for buyers and lenders.

Non-traditional or system-built houses were constructed using methods that differ from standard brick-and-mortar. They include concrete panel systems, steel frames, and timber or prefabricated structures. While they helped meet housing needs quickly, many of these designs later revealed long-term durability issues.

Approximately 26 construction types were officially designated as defective under the Housing Act. These properties may not meet standard mortgage lending criteria unless significant structural repairs or upgrades have been carried out under an approved scheme.

It’s important that your surveyor identifies the construction method and advises on any known risks or required investigations, particularly if a mortgage is being arranged. Not all system-built homes are problematic, but buyers should be made aware of any relevant design history or performance issues.