Design & Interiors

When Roof Tiles Rot, Cause Leaks

If one tile breaks or cracks while on the roof, replacing it or making repairs to avoid a leakage becomes very costly
If one tile breaks or cracks while on the roof, replacing it or making repairs to avoid a leakage becomes very costly. PHOTO | COURTESY 

Roof tiles can be flat or round or be made to look like wood shakes. Best still, they can be shaped to simulate centuries-old roofing materials, helping to whisper charm and elegance. The possibilities with roof tiles are virtually limitless.

With the growing desire for artistic buildings that can stand out, tiles are increasingly finding their way deeper in the hearts of almost all estates.

And the advantages are many—long lasting, classy, variety of colours to choose from, able to withstand strong winds and so on. Yet, masked in these advantages are also challenges that can prove costly to eliminate if no proper planning is made at the beginning.

Architect Florence Nyole, the vice-chairperson of architects’ chapter representatives at Architectural Association of Kenya cautions that a leakage that exposes the roof truss to water may make it to rot and eventually cave in.

“This can be avoided by having a proper underlay sheet made of either flat sheet of ‘mabati’ or heavy gauge polythene sheet. Proper installation is also important to avoid cracked or chipped tiles as they allow water to pass through,” she says.


Roofing Styles Kenya, a Nairobi-based firm that supplies and installs stone coated roofing tiles says that the market has many tiles that come in different prices and sometimes customers fall for cheaper ones to fit into their budget.

“Not all roofing tiles are created equal. You do not have to make the mistake of going for the wrong tiles so as to learn which ones are the best,” says the company.

And the mistake could be expensive. For some, it could be about replacing the faded roof. For some people, repairing the damage may call for not only replacing the tiles but also the roof structure that has been destroyed by rain water.

If one tile breaks or cracks while on the roof, replacing it or making repairs to avoid a leakage becomes very costly, according to Ms Nyole.

According to architects, choosing on the type of tiles long after the roof structure is complete is akin to trying to fit a round peg in a square hole and expecting it to be firm.

Ms Nyole, says that some roof structures can easily cave in with time if they are fitted with tiles that are heavier than had been planned for.

Clay tiles

She adds that clay roofing tiles are quite heavy compared to the stone coated roofing sheets and the common corrugated galvanised iron sheets.

“Clay roofing tiles require a structural engineer’s input to ensure the roof is well supported by a strong truss system as well as the correct truss material such as steel sections or timber sections. Without this, the weight of the tiles will make the roof to cave in,” says Ms Nyole.

This means that despite being loved for being cheaper as compared to stone coated tiles, a proper reinforcement needs to be made because of the heavy weight of the roof.

After about every 20 years the materials where the roof has been laid have to be replaced to avoid the roof from caving in.

Water harvesting

For those desiring to harvest water for home use, it is crucial to know the source of the roofing tiles, whether chemicals were used during the manufacturing process or not.

Ms Nyole says that one has to be specific of intended use at time of purchase if they are to get tiles that are chemical-free and able to harvest water for home use.

“Due to demand and supply balance, most tiles have chemicals added to them during the manufacturing process and one has to be specific when purchasing the tiles from well-known suppliers,” she notes.

Many homeowners love trees. Trees growing next to the house may break under the weight of branches, or snap off in harsh winds. Smaller branches may rip off tiles leaving the roof susceptible to leaks. But Mugo Mutembei, the CEO at Bristem Developers warns that without care, one may be forced to replace the tiles faster than they are prepared to.

One has to also clean leaves and any other debris off the roof, say at least once a month, according to Mr Mutembei.

“Usually, when such debris pile up on the roof, it starts decomposing or traps moisture that then seeps into the tiles. This may eventually get to the wooden support beams making it to rot,” he explains.

One broken tile could be all it takes for water to enter the house. If you happen to notice a trickling of water down the wall, it is likely that much damage has already happened.

And the bad news is that most of the time, homeowners don’t see the top of their roofs until something goes wrong, according to Aabco Roofing, a US based firm specialising in roofing.

“This is why it is important to have roof specialists visit your home regularly to oversee things with an expert eye, and ensure no problems arise,” advises Aabco.