Where either external hard landscaping or soil is allowed to touch the wall above the level of the damp proof course or ventilation bricks, "bridging can" occur leading to dampness problems within a property. The external ground level should be at least 150mm (6”) below the damp proof course. Where there are high ground levels, there may be a lack of sub-floor ventilation and also exposed timbers bearing onto the wall may be at risk from dampness and therefore may rot.
Situations where high ground levels may be present include
• Patios and other paved areas
• Garden walls
• Raised beds