Extended Ground Levels and Subfloor Ventilation

Extended Ground Levels and Subfloor Ventilation

Extended ground levels and subfloor ventilation are two important areas in a survey for both Homebuyer Reports and Building Surveys.

Extended Ground Levels

Extended ground levels should be at least 150mm (or two bricks) below a damp proof course. On older period properties, this distance should be greater – 200-250mm below finished floor level.

This can sometimes be difficult to identify when the external wall is rendered. Where render is taken down to the ground it should be ‘hacked’ back above damp proof course or floor level and finished with a ‘bell drip’ which will help push water away from the walls.

Subfloor Ventilation

Sub-Floor ventilation is important when a property has a suspended timber ground floor. Air circulation helps to prevent rot to timbers from dampness.

Having a sufficient number of vents is important and these should be maintained in a good condition to help prevent against rodent access and to allow a good through flow of air.