Asphalt shingles – ridges or peaks formed in the roof surface

Cause

Movement of the underlay 

Repair

  • the only satisfactory solution is to replace the roof, laying new shingles over a suitable (plywood) substrate; ensure that roof space ventilation is provided. If the old asphalt shingle roof has met minimum Building Code durability provisions (it has lasted at least 15 years) a building consent is not required; if not, a consent must be obtained before reroofing.

Cause

Timber sub-structure shrinkage 

Repair

  • the only satisfactory solution is to replace the roof, laying new shingles over a suitable (plywood) substrate; ensure that roof space ventilation is provided. If the old asphalt shingle roof has met minimum Building Code durability provisions (it has lasted at least 15 years) a building consent is not required; if not, a consent must be obtained before reroofing.

Cause

Inadequate ventilation of the roof space 

Repair

  • the only satisfactory solution is to replace the roof, laying new shingles over a suitable (plywood) substrate; ensure that roof space ventilation is provided. If the old asphalt shingle roof has met minimum Building Code durability provisions (it has lasted at least 15 years) a building consent is not required; if not, a consent must be obtained before reroofing.

Cause

Use of sarking (planks) instead of sheet plywood 

Repair

  • the only satisfactory solution is to replace the roof, laying new shingles over a suitable (plywood) substrate; ensure that roof space ventilation is provided. If the old asphalt shingle roof has met minimum Building Code durability provisions (it has lasted at least 15 years) a building consent is not required; if not, a consent must be obtained before reroofing.