Roof Inspection. Think your roof is safe? Think again!

Interview with Tinus and Stian de Jager

Is a building safe for continued occupation and use once the occupation certificates are issued? Most people would have thought so, but that isn’t the case. Building owners are actually required by law to carry out regular inspections to ensure the structural safety of their buildings.

Tinus & Stian de Jager - TrussVision

Tinus and Stian de Jager from TrussVision, a company which specialises in carrying out inspections of roof structures and assisting with their repair, tell Asset just what an important aspect of safety this is.

The regulations that have to be followed during the design and construction phases of a building are well known. As Tinus points out, a building must comply with the requirements set down in the Building Standards Act and the National Building Regulations in order to be given an occupation certificate by the local authority. Legal compliance doesn’t and there, however. There is a further requirement in the Oc


cupational Health and Safety Act (Act 85 of 1993) (Section 11(2)) which states:

An owner of a structure must ensure that:

  • Inspections of the structure are carried out periodically by competent persons in order to render the structure safe for continued use;
  • That the inspections contemplated in paragraph (a) are carried out at least once every six months for the first two years and thereafter yearly;
  • The structure is maintained in such a manner that it remains safe for continued use.


It is because most building owners are not aware of this fact that many of the roof structures that Tinus and Stian have seen over the years are in fact not safe. Structural failures are known to have occurred, causing losses and damage for landlords and tenants alike. Worse yet, landlords would be held responsible for injuries or deaths occurring as a result of such structural failures.

So why isn’t the regulation more commonly known about? Tinus and Stian believe that one possibility is because it appears in the Occupational Health and Safety Act rather than the Building Standards Act or the National Building Regulations. It just isn’t in a place where most building owners might think to look when making themselves aware of their responsibilities – and once a new building is signed off and certified as safe for occupancy, no one thinks very much further about it.

Yet, as these two gentlemen have seen firsthand, there is a good reason to require regular structural integrity inspections – particularly in the case of roof structures. Timber, which is used for constructing many roof structures in South Africa, actually loses some of its strength in the early part of its life. Stian explains that this loss of strength does decelerate and eventually stabilise, and that safety factors are built into the architectural and engineering designs, and into the timber ratings, to try and ensure that the correct timber is used. “However, there can still be major and minor non-compliances when it comes to construction and installation, some failures, or apparent or inherent defects that could result from design, manufacturing or installation,” he says. “A structure older than 20 years might not even have been inspected, so there is room for things to go wrong.”

Tinus and Stian have developed their business on the basis of helping business owners comply with the requirements of the Occupational Health and Safety Act, protect their own commercial and financial interests, and be responsible corporate citizens. They have carried out work for the likes of listed Property Fund EMIHA, for which they did a complete Gauteng portfolio inspection and oversaw all the necessary remedial work. Emira was one of the forward thinking property funds to set the example and take the lead in securing that their entire portfolio is checked and certified to be “safe for continued use.”

Other funds and building owners are also starting to become more aware of the potential problems that could arise from structural failures, and the liabilities that they could face in the event of injuries or deaths. The service that Tinus and Stian offer through Truss-Vision will go so far as to inspect every building in a portfolio, to report back to the client on every minor or major issue, and to oversee the remedial work which makes the structure safe for continued use.

“We check for a range of things. The first is on non-compliance as far as roof erecting procedures are concerned, because there are basic procedures which might not have been followed,” Tinus explains. ‘We look for timber deformations — things like buckling, bending and breaking which are typical after the first ten or 15 years of a building’s life, and which aren’t always obvious but can nevertheless be potentially problematic.”

Roof truss remedies
Roof truss inspection
Roof repairs

The next step is to make recommendations to the client. In many cases, as Tinus points out, building owners need some assistance when it comes to implementing those recommendations, so a further aspect of the service offered includes compiling a bill of quantities for the work to be done and putting the contracts out to tender_ “This way, the client doesn’t get a whole range of different quotes in from people who believe that different things need to be done. They are able to compare like for like,” he adds.

With their backgrounds as engineers and roof inspectors, Tinus and Stian are able to monitor the remedial work and ensure that it is done correctly. They are both members of the Institute for Timber Construction, which is the regulatory body that regulates the timber roofing industry. “The industry is generally fairly well regulated on the design and manufacturing side, but the erectors aren’t as well regulated as they could be. I’d say that poor workmanship accounts for probably 80% of the issues that we see,” Tinus comments.

Stian adds that this largely comes down to a lack of training, which is not just about the physical assembly, but also involves interpret-ing drawings correctly. ‘We work quite closely with Prof Burdzik from the University of Pretoria, who we often consult on tricky designs, and who has assisted us in the past in putting together the correct details for remedial work. His comment bus was that we’d need to be on site regularly, monitoring the way things are done – so that’s what we do. We climb into those roofs and spend time helping the contractors to do the job right,” he says.

This ensures that the remedial work is done properly so that the roof structure can be signed off for the coming year. “The remedial work should last for the lifetime of the building if it is done properly, so we can say that the structure is safe for continued use and check again in a year, and in the meantime the client knows they have guaranteed work,” Tinus adds.

Much has changed in the timber roofing industry over the past few decades – including the quality of the timber (which is now grown much faster are actually performs differently from much older timber), workmanship and training. All this combines to mean that whereas one might have been able to rely on a roof structure holding up without a problem 50 years ago, it isn’t worth the risk today. Certainly for commercial landlords, the potential costs of repairing structures and relocating tenants, not to mention the risk of injury to occupants, is not worth it.

“lf you look at the cost of addressing these problems and compare it to our fee, which is usually in the region of about R6 to R8 per square meter, it’s a drop in the ocean,” Tinus maintains. “Our goal isn’t to burden our clients with additional heavy costs for inspections – it is to transform the industry, steer it out of a potential crisis, and hopefully raise aware-ness about some of the broader issues that need addressing,” he adds. In the meantime, TrussVision is focused on providing a service to clients which will help them comply with legal requirements, which protects their financial and commercial interests, and which keeps building occupants sale and sound.

Published in Asset, Issue 56, October 2017 
Interviewed by Tony Korsten
Written by Claire Cole
Photographed by Tony Korsten