Defects built into a New House, in Bulimba, an eastern suburb of Brisbane.

Defects with new house design. Identified by Peter Weddell, owner/operator of Qld Home Buyers Inspection Service and Queensland Building Inspection Service, QBIS.

Water entry occuring to interior of this new house because of poor design is inevitable

Steps leading down to the main entry of this new house are higher than the living area slab level, creating a pit.

Although a drain has been fitted, it is unlikely to  allow the water to escape quickly enough before allowing water to enter the house. What can make matters worse, is when the drain becomes blocked.

Recommended rectification:

Create an open trench from the drain level through the retaining wall to a lower point of the property and/or to the street. This would need to be sufficient in its size to allow water to escape, in adverse weather conditions.

Low area at front of the house with inadequate drainage. This will trap water with no chance of it being diverted to the street.

Design defects in new house

Insufficient differences between the paving and inside slab level:

Paving has been fitted only 30 mm lower than the inside slab level of a living area. This is likely to allow water entry to interior of the house in differing weather conditions.

Recommended rectification:

Fit large open drains that can be easily checked and kept clear of debris.

Design defect of drainage with new house

From the inside showing the level differences between paving and inside.

Additional down-pipe fitted to help stop the roof gutter from overflowing.

Two down-pipes connected to the same size storm-water pipe reducing its effectiveness by half. This will cause backflow of water and possible rot to concealed timber of the eaves.


  • Fit an additional storm-water pipe to the down-pipes.
  • Fit relief slots to front edge of the roof gutter.

New house design defects. Important notes:

  • Builders must question faults in design if they consider them to be impractical.
  • Recommend workable solutions.
  • Design faults must be identified in the early stages, before their construction.
  • A healthy relationship must be developed between the builder and designer, in the best interest of the client.

Bottom line, Builders are responsible for the faults they build.

Related material that may be of use:

Qld Goverment Standards and Tolerances Guide

Learn more about new house design defects:

For independent Building Inspections Brisbane in all suburbs, Qld Home Buyers Inspection Service.