thedamp

DAMP PROOFING further info

Old buildings allow moisture to be absorbed by the fabric of the building and evaporate away naturally. This is what we call a ‘breathable’ fabric.

Breathability can be important when we consider the floors in old buildings, as they often consist of stone floors laid directly on the earth. In its original situation any moisture below the floor could rise to the floor surface to evaporate away with no detriment.

If we then install a concrete insulated floor with a dampproof membrane (DPM), any moisture below the floor will continue to rise and, as the floor is now impermeable, may get pushed to the walls where it could appear as damp spots.

The fundamental issue facing the owners of older properties is how to bring them up to modern standards with regard to heating, insulation, airtightness and freedom from damp.

BACKYARD
Drainage for property
Drop the current height to aus standards to allow for sub floor ventilation- what is that?
The ground levels are close to or covering some of the damp proof course (DPC) and subfloor vents to the rear external walls and the external levels should be lowered appropriately.

Ideally, the height of a damp proof course DPC should be not less than 150mm above the adjacent ground level; 75mm above the finished surface level of adjacent paved, concrete or landscaped areas that slope away from the base of the walls; 50mm above finished paved, concrete or landscaped areas that are protected from the direct effects of the weather by items such as carports, verandah, balcony etc.

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In our experience, termites most commonly enter over the slab edge and therefore we recommend modifications be made by lowering all grounds levels to expose the concrete slab edge as this is an undetected entry point for timber pest attack, see Section 4.0 – Concrete Slab Homes (part or full). The following items restricted access to the edge of the slab: Soil. Paths.