RICS Level 2 Survey in CR0

CR0 spans a broad and mixed stretch of South London. Sales data points to terraced homes making up 32.7% of transactions, flats 32%, semi-detached properties 21.8%, and detached houses 13.5%. That spread matters, because the right survey in this postcode depends heavily on what is being bought. For a flat, we need to look at the lease, the communal parts and the building fabric as a whole. On older Croydon terraces, we are often looking closely at solid wall dampness and Victorian rooflines.

Across CR0, and more widely through the London Clay belt, one of the main structural hazards is shrink-swell subsidence. In long dry spells, clay soils lose moisture and shrink, then expand again once saturated. Homes close to large established trees, with lime, oak, poplar, and willow among the worst offenders, carry a higher risk of differential foundation movement. One of the first things we check is the characteristic diagonal cracking linked to this form of subsidence.

Croydon saw heavy housebuilding in the inter-war period, and 1930s homes in places such as Croham Manor Road, South Croydon, now within a conservation area, remain in strong demand. They were usually built well. Even so, they are now 80-90 years old, and many have been through several rounds of repairs and alterations. Our team knows the defect pattern that commonly comes with this period of construction.

• Clay geology throughout south London creates shrink-swell subsidence risk
• Significant inter-war and Victorian housing stock with age-related defects
• Conservation areas at Addington Village and Croham Manor Road requiring care
• High proportion of flatted stock needing communal area and lease checks
• Surface water flooding risk in lower-lying parts of CR0
• Pre-1980 properties likely to need electrical and plumbing system review
• Damp is common in solid-walled pre-war terraces

Large parts of south London, including substantial sections of CR0, stand on London Clay. For residential property, that geology creates one of the capital's most common structural risks. Clay soils are prone to volumetric change. In dry summers they shrink and crack, and in wet periods they take on moisture and swell. That repeated movement can lead to differential settlement in foundations, especially where tree roots have dried the clay out.

Tree-lined streets are common in CR0, and that mix of clay subsoil with long-established root systems can create the right conditions for subsidence. Where a property has been affected, we often see stepped diagonal cracking through brickwork at corners and above window and door openings, doors and windows that stick or shut unevenly, and floors that slope. Our surveyors are trained to judge whether cracking is old and stable or a sign of continuing movement.

If we find signs that may point to active foundation movement, we recommend specialist investigation, usually a structural engineer's report and sometimes a drain survey as well, since leaking drains can speed up clay desiccation. Picking that up early is one of the most useful parts of a pre-purchase survey. Subsidence claims are among the most expensive and disruptive problems to sort out, and insurers may attach conditions to cover where a property has a history of movement.

The age profile of housing in CR0 means some defects come up again and again in our surveys. Damp is especially common in solid-walled pre-war homes, where there is no modern damp-proof membrane to stop moisture rising through the masonry from the ground. We also frequently find penetrating damp caused by failed pointing, cracked render, and defective flashings where outside maintenance has been put off.

Roofing problems are among the issues we report most often in CR0. A good number of inter-war and post-war homes still have roofs at, or beyond, their economic service life, with concrete or clay interlocking tiles laid over worn roofing felt, deteriorated timber battens, and lead valley gutters and flashings that have simply reached the end of the road. If a roof is near the end of its serviceable life, we say so clearly in the report so replacement costs can be reflected in the offer.

Another regular finding is an outdated electrical installation, especially in homes that have seen little upgrading since they were first built. Consumer units installed before RCD protection standards, rubber or aluminium wiring, and extensions completed without electrical certification all merit further checking by a qualified electrician. We flag each of these points in the report and set out the follow-up we think is needed.

• Rising and penetrating damp in pre-war solid-wall properties
• Worn roof coverings, tiles, felt, and lead flashings
• Cavity wall tie corrosion in properties built 1935-1980
• Subsidence-related cracking on clay subsoils
• Outdated electrical consumer units and wiring
• Older plumbing systems, including potential lead pipework
• Asbestos-containing materials in pre-2000 buildings