Waterproof decks – the deck is springy

Cause

There is damage to the substrate and/or framing due to water entry through the membrane or through adjacent wall claddings 

Repair

  • check the roof structure from below for evidence of water ingress and substrate/framing deterioration 
  • if the framing is sound but the substrate is damaged, contact a specialist applicator to remove the membrane and the substrate; replace the substrate using H3 CCA-treated, 17.5 mm plywood; replace the deck membrane
  • if the substrate is particleboard, it must be replaced with H3 CCA-treated, 17.5 mm plywood 
  • if moisture is present, identify the source of water entry and remedy; employ a specialist to carry out repairs
  • where it is suspected that the building may be leaking and there is a risk of damage, engage a building surveyor to report on the building and advise on repair/replacement options. A building consent will be needed for repair work

Cause

The substrate material is not thick enough to span the rafters/joists

Repair

  • check the roof structure from below for evidence of water ingress and substrate/framing deterioration 
  • if the framing is sound but the substrate is damaged, contact a specialist applicator to remove the membrane and the substrate; replace the substrate using H3 CCA-treated, 17.5 mm plywood; replace the deck membrane
  • if the substrate is particleboard, it must be replaced with H3 CCA-treated, 17.5 mm plywood 
  • if moisture is present, identify the source of water entry and remedy; employ a specialist to carry out repairs
  • where it is suspected that the building may be leaking and there is a risk of damage, engage a building surveyor to report on the building and advise on repair/replacement options. A building consent will be needed for repair work

Cause

The particleboard used as a substrate has deteriorated

Repair

  • check the roof structure from below for evidence of water ingress and substrate/framing deterioration 
  • if the framing is sound but the substrate is damaged, contact a specialist applicator to remove the membrane and the substrate; replace the substrate using H3 CCA-treated, 17.5 mm plywood; replace the deck membrane
  • if the substrate is particleboard, it must be replaced with H3 CCA-treated, 17.5 mm plywood 
  • if moisture is present, identify the source of water entry and remedy; employ a specialist to carry out repairs
  • where it is suspected that the building may be leaking and there is a risk of damage, engage a building surveyor to report on the building and advise on repair/replacement options. A building consent will be needed for repair work