Fibre-cement cladding too close to or in ground contact

Causes

Cladding was installed too close to the ground

Gardens have been built up

Path or paving laid against the cladding

Listed under: Exterior, concrete and cement, fibre-cement, cladding, walls, wall cladding, fibre-cement cladding

Cause

Cladding was installed too close to the ground

Repair

  • aim for a minimum 30–50 mm gap between the base of the cladding and the ground to prevent moisture uptake. The easiest way to achieve this may be by lowering the soil or garden level so it is clear of the cladding – the bottom of the cladding must be able to dry completely. Ensure that lowering the garden level does not lead to rainwater flowing under the house.

  • check cladding for dampness or damage. Repair or replace as necessary

  • with suspended floors, ensure good subfloor ventilation:

    • there should be not less than 3500 mm² of clear open subfloor venting for every 1 m² of floor area

    • ventilation openings should ideally be high in the subfloor space, near to the underside of bearers

    • vents should be spread evenly around the building perimeter to allow cross-ventilation

    • no part of the subfloor should be more than 7.5 m from a ventilation opening.

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Cause

Gardens have been built up

Repair

  • lower the soil/mulch level so it is clear of the cladding – the bottom of the cladding must be able to dry completely. Leave a minimum 30–50 mm gap between the base of the cladding and the ground to prevent moisture uptake. Ensure that lowering the garden level does not lead to rainwater flowing under the house

  • check cladding for dampness or damage. Repair or replace as necessary

  • with suspended floors, ensure good subfloor ventilation:

    • there should be not less than 3500 mm² of clear open subfloor venting for every 1 m² of floor area

    • ventilation openings should ideally be high in the subfloor space, near to the underside of bearers

    • vents should be spread evenly around the building perimeter to allow cross-ventilation

    • no part of the subfloor should be more than 7.5 m from a ventilation opening.

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Cause

Path or paving laid against the cladding

Repair

  • where possible, break up and remove concrete or paving. Reform the ground surface so there is a minimum 30–50 mm gap between the base of the cladding and the ground and ensure that rainwater will flow away from the building

  • check cladding for dampness or damage. Repair or replace as necessary

  • with suspended floors, ensure good subfloor ventilation:

    • there should be not less than 3500 mm² of clear open subfloor venting for every 1 m² of floor area

    • ventilation openings should ideally be high in the subfloor space, near to the underside of bearers

    • vents should be spread evenly around the building perimeter to allow cross-ventilation

    • no part of the subfloor should be more than 7.5 m from a ventilation opening.

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