From the Tales of Woe Archives: Problems Arising Out of Site Dimensions
Owner points out boundary position lies just inside a thick wide hedge. Architect designs a building to the maximum allowed by height to boundary controls. Regrettably, owner is mistaken, and the boundary is at the other side of the hedge, and at a much lower level.
Architect obtains survey and to the maximum allowed by height to boundary controls. But the Surveyor’s drawing is misunderstood to show the boundary at the top of a retaining wall instead of at its base.
Builder thinks the architect is a wally; after discussion/agreement with the owner helpfully raises the floor level 200mm without the architect being told or noticing on a site visit. HIRB encroachment discovered when neighbour complains.
Boundary levels are more or less consistent, except for a small section which has a pronounced dip about 1.2m across and 400mm deep. Architect ignores it but the council doesn’t!
Construction proceeding smoothly, framed up with roof about to go on. Some bright spark in the check-box department of the local council realises that they have not yet got a certificate from a surveyor to verify the HIRB (side yard width) and sends out a routine letter. Architect sadly discovers that the required clearance has been taken from the dimension line on the drawing, not the building itself.
Old house in poor condition and warped floor is to be repiled, refurbished and extended along the boundary. Site levels are taken before the design is started. Floor level of the extension is designed to be level through to the existing old house. But after the repiling there is an embarrassing step between old and new.
(Many cases!): Design relies on previously recorded position of existing subsurface services; subsequent excavation for some vital part of the new structure reveals a direct clash between existing services and new foundations.
(Many cases!): Setout dimensions inconsistent either on the drawing or another one; inevitably the wrong dimension gets built!
