05/07/2026
๐๐ข๐๐ ๐๐ข๐๐ฆ๐ง ๐๐ข๐ ๐ ๐ข๐ช๐ก๐๐ฅ ๐ช๐๐ฆ ๐ง๐ข๐๐ ๐จ๐ฅ๐๐๐ก๐ง ๐จ๐ก๐๐๐ฅ๐ฃ๐๐ก๐ก๐๐ก๐ ๐ช๐๐ฆ ๐ฅ๐๐ค๐จ๐๐ฅ๐๐ ๐๐ข๐ฆ๐ง๐๐ก๐ ๐ง๐๐ข๐จ๐ฆ๐๐ก๐๐ฆ ๐ข๐ ๐๐ข๐๐๐๐ฅ๐ฆ. ๐ง๐๐๐ก๐ ๐๐ข๐ข๐๐ก๐๐ฆ๐ฆ ๐๐ ๐๐ข๐ก๐ง๐๐๐ง๐๐ ๐๐ข๐ฅ๐๐ก๐ฆ๐๐ ๐๐ก๐๐๐ก๐๐๐ฅ๐ฆ ๐๐ข๐ฅ ๐๐ก ๐๐ก๐๐๐ฃ๐๐ก๐๐๐ก๐ง ๐ฅ๐๐ฃ๐ข๐ฅ๐ง, ๐๐๐๐๐จ๐ฆ๐ ๐ช๐ ๐๐ข๐จ๐ก๐ ๐๐ง ๐ฆ๐๐ ๐ฃ๐๐ฌ ๐ช๐๐ฆ ๐ก๐ข๐ง ๐ง๐ฅ๐จ๐. ๐๐๐ฅ๐ ๐๐ฅ๐ ๐ฆ๐ข๐ ๐ ๐ฅ๐๐ฃ๐ข๐ฅ๐ง ๐๐๐๐๐๐๐๐๐ง๐ฆ.
๐ฃ๐ฅ๐ข๐ฃ๐๐ฅ๐ง๐ฌ ๐๐๐ฆ๐๐ฅ๐๐ฃ๐ง๐๐ข๐ก
The house comprises;
โข Multi-level
โข Masonry, stud & blueboard walls
โข Slab on ground, suspended slab & timber floors
โข Tile roof
๐๐๐ก๐๐๐ก๐๐ฆ
Exterior
โข Garage left entry, erosion void under edge of firewall footing
โข Similar slight erosion noted under edge of firewall of units 7&8
โข Front storm water downpipe not vertical (as installed)
โข Front wall some blueboard sheet joint edge gaps, some blueboard crack repairs
โข Front driveway (old) cracks
โข North wall some crack repairs
โข West outdoor living roof beam joint seal split
Interior
โข Garage slab cracks
โข Garage & store wall cracks, ceiling (slab) fine cracks
โข Family/dining (added) stud wall edge gaps
โข Kitchen bulkhead some edge cracks
โข Some door architrave /wall gaps
โข 3rd level window reveal trim wear & some ceiling sheet edge gaps
โข 2nd level laundry wall crack
โข 2nd level hallway & bed 3 wall cracks
๐๐๐ข๐ข๐ฅ ๐๐๐ฉ๐๐๐ฆ
*Relative zero was reset for each floor. Test locations are approximate and may be restricted by household items. Carpet wear affects readings, bathroom slabs fall to the floor waste and garage floor slabs are often finished with a fall to the door. Unit 9 (adjacent) recorded a level of -11 at the front left entry
We took levels on the floors (illustrated in mm in red highlights). There are some variations that would be โas finishedโ levels and also floor level variations which are likely to be associated with some slight ground movements. It is our interpretation that any floor level variations caused by ground movements are minimal, and are well within the allowed tolerances of AS 2870 appendix C and table 4.1.
๐๐ฅ๐๐๐ ๐๐๐ง๐๐๐ข๐ฅ๐๐๐ฆ
Wall cracks are up to category 2 in accordance with AS2870-2011 Appendix C. Garage slab cracks are category 1 in accordance with AS2870-2011 Appendix C
๐๐๐จ๐ฆ๐๐ฆ
๐๐ผ๐๐ป๐ฑ๐ฎ๐๐ถ๐ผ๐ป ๐๐ผ๐ถ๐น ๐บ๐ผ๐๐ฒ๐บ๐ฒ๐ป๐๐
Our local experience indicates that the founding soils of the housing estate consist of clean landfill which was pre-consolidated prior to commencement of construction.
Although the quality density of the founding material would be certified by civil engineers as a suitable standard for high level footing construction, there can be some slight initial / normal footing settlements under applied loads which are within design tolerances.
Some landfill can also have the capacity to shrink and swell with variations in moisture content โ again which is generally not significant and within design tolerances.
In this case it is likely that there has been some slight initial footing/slab settlements which caused some cracks & gaps. In addition, some current, slight footing & slab movements is likely to be a contributing factor.
๐ฆ๐ฒ๐๐๐น๐ฒ๐บ๐ฒ๐ป๐๐, ๐ฑ๐ฟ๐ฎ๐ถ๐ป๐ & ๐ฒ๐ฟ๐ผ๐๐ถ๐ผ๐ป.
We could not identify any evidence or likelihood that the slight erosion under the garage firewall edge has caused any settlements or footing/slab instability.
๐ข๐๐ต๐ฒ๐ฟ ๐ฐ๐ฎ๐๐๐ฒ๐ ๐ผ๐ณ ๐ฐ๐ฟ๐ฎ๐ฐ๐ธ๐ & ๐ด๐ฎ๐ฝ๐
The building elements; blueboard, concrete, plasterboard & framing can undergo differential expansion and contraction with variations in temperature and humidity.
This can be exacerbated by the quality of finishing and fitments at the construction stage.
๐๐ฎ๐ฟ๐ฎ๐ด๐ฒ ๐ณ๐น๐ผ๐ผ๐ฟ ๐๐น๐ฎ๐ฏ ๐ฐ๐ฟ๐ฎ๐ฐ๐ธ๐
The cracks in the garage floor are โplastic shrinkage cracksโ which would have originated shortly after the slab was poured. The cracks occur due to concrete shrinkage as it cures and the cracks generally grow as the surface edges wear and they become more visible as they collect dirt. They are not a structural defect.
๐ฅ๐๐๐ข๐ ๐ ๐๐ก๐๐๐ง๐๐ข๐ก๐ฆ
๐๐ฟ๐ถ๐ฒ๐ณ
๐ง๐ต๐ฒ๐ฟ๐ฒ ๐ถ๐ ๐ป๐ผ ๐ฒ๐๐ถ๐ฑ๐ฒ๐ป๐ฐ๐ฒ ๐ผ๐ฟ ๐น๐ถ๐ธ๐ฒ๐น๐ถ๐ต๐ผ๐ผ๐ฑ ๐ผ๐ณ ๐ฎ๐ป๐ ๐๐ถ๐ด๐ป๐ถ๐ณ๐ถ๐ฐ๐ฎ๐ป๐ ๐บ๐ผ๐๐ฒ๐บ๐ฒ๐ป๐๐ ๐ผ๐ณ ๐๐ต๐ฒ ๐ณ๐ผ๐ผ๐๐ถ๐ป๐ด๐ ๐ผ๐ฟ ๐๐น๐ฎ๐ฏ๐ and in particular there is no evidence that the unit 10/unit 9 garage common firewall and slab have sustained any settlements as a consequence of the erosion from the storm drain.
๐๐ป๐ฑ ๐๐ต๐ฒ๐ฟ๐ฒ ๐ถ๐ ๐ฐ๐ฒ๐ฟ๐๐ฎ๐ถ๐ป๐น๐ ๐ป๐ผ ๐ฟ๐ฒ๐พ๐๐ถ๐ฟ๐ฒ๐บ๐ฒ๐ป๐ ๐๐ผ ๐๐๐ฎ๐ฏ๐ถ๐น๐ถ๐๐ฒ / ๐๐๐ฝ๐ฝ๐ผ๐ฟ๐ ๐๐ต๐ฒ ๐ด๐ฎ๐ฟ๐ฎ๐ด๐ฒ ๐ณ๐ถ๐ฟ๐ฒ๐๐ฎ๐น๐น ๐ณ๐ผ๐ผ๐๐ถ๐ป๐ด ๐ฎ๐ป๐ฑ/๐ผ๐ฟ ๐๐น๐ฎ๐ฏ ๐๐ถ๐๐ต ๐ฎ๐ป๐ ๐๐๐ฝ๐ฒ ๐ผ๐ณ ๐๐ป๐ฑ๐ฒ๐ฟ๐ฝ๐ถ๐ป๐ป๐ถ๐ป๐ด.
๐ฅ๐ฒ๐ฝ๐ฎ๐ถ๐ฟ๐
โข The storm drains should have sealed connections and seepage should not be allowed under the footing ot slab edges. The void can be plugged with non-shrink cementitious grout.
โข The exterior blueboard sheet edge gaps can be repaired by raking out and sealing with polyurethane compound such as Sikaflex 11FC.
โข Any exterior door & window frame gaps can also be sealed with SIKAFLEX 11FC or similar.
โข Interior ceiling & wall cracks can be filled and painted. Use of fibreglass joint tape is recommended.
โข Garage floor cracks do not require repair
โข Masonry and concrete cracks can be raked out and repaired with high bond strength non-shrink cementitious grout.
๐๐๐ผ๐พ๐ ๐๐ ๐๐๐๐ฟ
If your house develops cracks and gaps, Do yourself a favour.
Before jumping into any kind of expensive underpinning, it is essential to get an independent engineer report to find out is it is actually necessary and if it is, then which type is the most appropriate.
๐๐๐ ๐๐๐พ๐ ๐ฟ๐๐๐ ๐ผ๐ ๐๐๐๐๐๐๐๐ ๐๐๐๐๐๐ ๐พ๐๐๐?
An expert RPEQ Engineer subsidence Report from Forensic Engineers generally costs between $650 - $900 ex GST. (local service area only).
๐๐๐ฟ๐๐๐๐๐๐๐๐ ๐ผ๐๐๐ผ๐๐๐๐๐ ๐๐๐๐๐๐๐๐ ๐๐๐๐๐๐๐ ๐๐๐ ๐๐๐
Some underpinners offer to arrange a report from their own engineer. Tฬฒhฬฒeฬฒ cฬฒฬฒoฬฒsฬฒtฬฒ iฬฒฬฒsฬฒ cฬฒฬฒoฬฒnฬฒsฬฒiฬฒdฬฒeฬฒrฬฒaฬฒbฬฒlฬฒyฬฒ mฬฒฬฒoฬฒrฬฒeฬฒ tฬฒฬฒhฬฒaฬฒnฬฒ fฬฒoฬฒrฬฒeฬฒnฬฒsฬฒiฬฒcฬฒ eฬฒnฬฒgฬฒiฬฒnฬฒeฬฒeฬฒrฬฒsฬฒ. Aฬฒnฬฒdฬฒ tฬฒฬฒhฬฒeฬฒrฬฒeฬฒ iฬฒฬฒsฬฒ aฬฒฬฒ hฬฒฬฒuฬฒgฬฒeฬฒ cฬฒฬฒoฬฒnฬฒfฬฒlฬฒiฬฒcฬฒtฬฒ oฬฒฬฒfฬฒ iฬฒฬฒnฬฒtฬฒeฬฒrฬฒeฬฒsฬฒtฬฒ.
Forensic Engineers reports are 100% independent. We are not working for, or paid by an underpinner and we are certainly not trying to sell you any type of underpinning.
๐๐ผ๐๐ ๐๐ ๐๐
Before committing to any type of underpinning, for peace-of-mind, contact us at Forensic Engineers for a chat and an independent opinion. We also strongly advise sending your own independant Engineer Report to at least three underpinning companies for quotes before making a decision.
www.forensic-engineers.com.au
E: [email protected]
Ph: 0403 434 092
