Early cavity walls
The Victorians experimented with cavity walls to fight penetrating dampness and improve thermal insulation. Builders used various methods to tie the two leaves of masonry together but by far the most common was the iron tie.
Danger: Today, these are often found to be corroding, which can lead to instability, unevenness and cracks in external walls. Modern methods of repair are economical and unobtrusive, provided the defect is diagnosed in time.
Slate became a common form of roofing material and usually, slates and tiles were fixed with iron nails. The best work used copper nails onto battens but without felt, which was a later innovation.
Danger: Although, slates are fairly resilient to the weather, the iron fixings corrode and fail. Rusting nails also tend to split the slates and tiles, which, if loose, can fall and prove lethal. Without felt, failure of this type can lead to the need to strip and renew the roof covering.
Larger buildings had ornate architectural details, which often included decorative bargeboards and plaster or terracotta mouldings. Staff regularly maintained these.
Danger: Nowadays, many larger Victorian villas have been converted into flats, but often little routine maintenance results in these features deteriorating or having to be removed – and they are expensive to replicate or replace.
The Victorians addressed ground-borne dampness by providing walls with damp proof courses, typically formed with slate or pitch and sand.
Dangers: Later alterations can lead to the damp proof course being breached and the need for remedial work. Frequently, they were often built too close to the ground, meaning they often become covered by earth and paving making them ineffective. Chimneys were often built without a damp proof course. So, the chimneybreasts become damp and the plaster is affected by salts, which can be difficult to overcome economically.
The sanitisation of housing brought the introduction of drinking water supplies to each house. Lead was commonly used for the underground pipe as this was largely resistant to corrosion.
Danger: Nowadays, we know that lead deposits in drinking water can damage health, particularly in small children. Lead pipes can also wear out and begin to leak due to abrasive action over the years.
Remedy: all lead pipe work should be replaced. In country properties, if there is an extensive length of underground pipe to replace, this can prove expensive.
Decorative floor tiles
The Victorians admired early Roman floors and emulated them with elaborate patterns in coloured tiles. The Dalton works in South London were a major producer and supplier of these to properties built in Surrey.
Danger: These floors do not contain a damp proof membrane. They should not be covered with impervious carpet or underlay as this traps the damp and can lead to problems.
David Lewis is a chartered surveyor with the Godalming-based practice Grillo LLP (01483 860 600; www.grillollp.com)