The rainy season is here when showers and heavy downpours are common place, causing puddles, flooding and damage, in some cases, to the built environment.
Rain is the ultimate integrity test for any type of roof. So significant is a leak-free roof that it is reflected in the ‘defects liability period’ of a standard building contract which states clearly that a building must weather the storm of, at least, one rainy season before it is deemed to have been successfully completed.
From the facility manager’s point of view, this is the time to seize the opportunity to focus regular inspections on the roofs, ceilings, eaves and upper parts of the facility in order to sweep out those tell-tale signs of failure in order to nip any damage in the bud. Plastic buckets strategically positioned to take water during the rains send a bad signal of inefficient maintenance practice.
The roof is one of the most important components of a building. It is that portion of the building that offers protection against sun and rain without which the content of the structure may be damaged.
The performance of a roof is measured based on its life span and effectiveness to retain its strength, chemical and physical properties, appearance and resistance to all forms of failure. Roof designers often take into account a number of design factors such as: -Tolerance and safety considerations, – workmanship, – Aesthetics, – Maintenance, – Height of the building, and Quality materials.
Any roof devoid of these considerations will manifest roof failures, the consequences of which are usually devastating to the extent that they sometimes claim lives and valuables.
The most common material used for roof trusses is wood. It is relatively cheap and readily available. These qualities give wood trusses an edge over iron for small-to-medium-sized buildings but in larger ones such as industrial buildings, steel trusses are used to provide stability against increased wind loads due to the height of these buildings.
Some roofs are constructed using reinforced concrete and require no trusses. Depending on the design, strength, density and installation techniques, the pores in the concrete may allow water to penetrate by capillary action and osmotic effects.
Good detailing practices for parapets, corners, guttering, down pipes and water proofing are essential considerations in the design and construction of a reinforced roof such that flow paths lead to suitable discharge points and ensure an impermeable membrane that keeps water out of the building.
There are different types of roofing materials but one commonly used in Nigeria is the aluminum roofing sheet.
Roofing done using corrugated iron sheets is chosen by many because of the low initial cost. It is one of the cheapest compared to the others but it has the disadvantage of rusting after some time and the rust level can become so high that it looks unsightly. If it is not changed by this period, leaks start to occur.
The facility manager’s approach to roof maintenance should be to have a schedule with special focus on critical areas which include but not limited to the following:
* Periodic confirmation of the integrity of bolted connections ensuring that all elements are adequately secured.
* Replacement or upgrade of accessories that show signs of deterioration.
* Check parapets for failure and cracks.
* Regularly clear guttering and down pipes of debris to avoid blockage.
* Confirm the effectiveness of water proof membrane in the case of reinforced concrete roofing.
* Eliminate ponding and stagnation if prevalent.
With these proactive guidelines, the facility manager is confident the roof is in good condition.
