How to avoid building defects

Very few people realize how important it is to know the soil properties on which their dream house will be built. The estate agents or developers use clever tactics claiming that only 3 things are the most important when buying the stand, erf or plot, these are: location, location, location!

When one thinks carefully it is easy to convince potential clients that this particular location is perfect;s near schools, near highway (good access everywhere), far from highway (no noise), near shopping mall, far from city, in the city, in a 'good' suburb, close to “good” suburbs, etc.  The building site is bought “voetstoet” and the first mistake is made.  There is a high probability that this land was bought without knowledge of soil conditions, which were not mentioned during a transaction.

Geotechnical Reports

First, find out whether a geotechnical report is available either from the owner or developer. If the land is the part of the township development, the developer most certainly will have one available. If not, try to contact local municipality inspectors who know the area and inquire about the soil conditions. Look also at the neighboring properties and ask owners if they have any problems with cracking of houses. Sometimes however, they hide problems with their houses, as they want to sell them. Look at the houses around and boundary walls and see if any cracks are already there.

Make sure you state clearly to the estate agent that you are not going to buy this land unless the geotechnical report is available. You will be surprised how quickly you will have one. If not, it will be worth to find the geotechnical engineer and ask him to prepare such report. This usually involves digging of few test holes to see the soil layers and a check for ground water levels. Such report may also contain some recommendations as far as the foundations are concerned.  You will immediately see what is waiting for you during construction. One must also be aware that in major cities all the good sites are already sold and the ones available for sale might not have ideal soils.

For the names of geotechnical engineers in your area contact SAICE (South African Institution of Civil Engineers) - Geotechnical Division - see below. For further issues dealing with offer to purchase it will be worth to scrutinize the available literature such as given in reference [1].

References: [1] The Complete Book of OWNER BUILDING in South Africa. Struik Publishers. Cape Town. 2003 [2] NATIONAL HOME BUILDERS REGISTRATION COUNCIL (NHBRC).Home Building Manual. Part 1&2.

  source: all texts and images are copyright 2006 and belong to jacek winczewski