Commercial Roof Assessment & Roof Repair – A Case Study
The example listed below is indicative of a typical roof assessment and recommendations pertaining to commercial roof repair.
A full assessment was carried about on a commercial building complex in a neighbouring state to determine the points of water ingress, assessment of damage and evaluation of possible future problems related to the leakages. Our assessment included evaluating the performance of the existing roofing system to determine whether it was performing according to its specified function as well as identify failures which would inform possible future remedial action.
The building complex was 28 years old, featured a pitch type roof and the roofing material used was pierced fixed, Chromadeck type steel sheeting which had been replaced in 6 years earlier. Some roofing areas included polycarbonate sheeting, all of which ran into conventional box type gutters.
The assessment was conducted primarily by a on site, walk around inspection of the roof surface area as well as by using a FLIR Thermal camera. The following were inspected and assessed:
- Condition of the Roof Sheeting
- Roof Fasteners
- Flashings and gutters
- Roof penetrations
- General environment and
- Potential plant processes that could impact the viability of the roof and it’s supporting structure
Findings and their respective recommendations were broken down item by item so as to enable the complex’s owners to make a decision with regards to repairs and proposed budget allocation as well as time scale set for the repair and whether this would be done in stages or not.
Roof Assessment and Repair Recommendations
The findings included extensive mechanical damage to a large portion of the roofing material. There was also obvious signs of corrosion with areas surrounding steam venting systems particularly badly affected. Areas of the polycarbonate sheeting appeared to have suffered mechanical damage due to extreme wear. The roofing material’s heat retention was also found to extreme measured at 60.1 degrees Celsius at only 10H00 am.
The roof fasteners were found to generally be in a good condition with a small number requiring replacement as they were either loose, non existent or miss installed.
Flashings, closures & gutters were found to be in good condition and installed correctly thereby preventing water ingress. Some corrosion was detected on large sections o f most box gutters. Some blockages of down pipes was detected.
Roof penetrations for equipment such as roof extensions, ventilation fans, evaporator cooling units, steam exhausts, lifeline anchor points, roof irrigation and pipes which are located on the roof have the potential to cause enormous damage where these are not laid out, or installed correctly. It was found that many of these penetrations were problematic and allowing penetration of water. The roof coating around these penetrations were almost without exception, corroded. Sections of the factory roof showed clear signs of damage in proximity to steam outlets and vents.
Environmental factors also need to be taken into consideration when designing a roof structure and to this end the client’s roof was found to have suffered from the corrosive factory environment such that certain sections of the interior roof supporting structure had also been dangerously compromised.
The lifespan of any roofing structure correctly treated with a suitable waterproofing and coating system will be extend. It is critical that the correct roof waterproofing system is specified and that this is applied by skilled and competent contractors. An analysis of the existing waterproofing coating system showed that the system was failing, with delamination and brittleness seen throughout the roof exterior surface. The DIY type products used by the previous contractor were clearly inadequate for the industrial application within which the roof had been installed. Some of the previous waterproofing work was found to also be exacerbating the problem of water ingress in certain areas. It was also found that silicon was used which should be avoid at all costs on roofing applications.
Finally roof structures such as skylights will inevitably cause problems at some point in the future. In this case it was found that there were numerous problems that would always be a difficult fix because of the nature of the installation. Various top plates were corroded leading to a dangerous situation where people could slip and fall on puddles of water every time it rained.