Frequently asked questions
What is construction monitoring and why does council require it?
Construction monitoring is engineering observation and testing during the works to confirm that what is built matches what was designed and that the ground behaves as assumed. Where a design relied on specific engineering design or on a geotechnical assessment, the building consent will usually carry conditions requiring inspection at key stages, with the engineer issuing a PS4 construction review statement at the end. Without that record, the completion certification can stall.
What is a PS4 and who issues it?
A PS4 is a producer statement for construction review, issued by the engineer who carried out the review to confirm that, on the basis of the observations and testing undertaken, the work has been constructed in general accordance with the design. It is normally issued by a Chartered Professional Engineer and is relied on by the building consent authority when issuing a code compliance certificate. A PS4 cannot be issued retrospectively for work that was never observed.
At what stages is inspection usually required?
For geotechnical work the typical hold points are bulk earthworks and subgrade exposure, fill placement and compaction testing, foundation excavations before pouring, pile installation including founding depth and set, retaining wall embedment and drainage before backfill, and subsoil drainage. The exact schedule is set by the consent conditions and the design, and it is worth agreeing it with the contractor before work starts so inspections are not missed.