Nelson Kiprop, a quantity surveyor at MN Consultants answers some common questions about roofing 

  Q What roofing materials are available on the market?

There are various materials on the market. For example, at Roofings Ltd, there are galvanised iron sheets and pre-painted coloured iron sheets. 

They are available in different profiles of plain sheets, super-eco, super tile and eco-tile and many others. They have various gauges or levels of thickness which ranges from gauge 34 (0.17mm to 22 (0.60mm) thickness.

 Q How long does it take to replace a roof?

Re-roofing depends on the type of roof and whether there are inspections needed.

For a small family home, it can take a few days, but it can take up to a few months for large commercial projects. 

If your contractor manages the project closely and efficiently, it should move smoothly.

 Q How long should a roof last?

Like any other building component, roofs degenerate at different rates depending on many factors, like the quality of the original construction materials, the level of abuse, the level of maintenance and the appropriateness of design. 

There are poorly designed and badly installed roofs that go as few as six or seven years, and then suffer wear and tear. 

It is important that you ask what the service life is; you might be surprised to find that many of them do not last for the full warranty and manufacturers’ warranties. 

 Q If my roof leaks, do I need to have it totally replaced?

Depending on the cost, you can replace the entire roof. If you cannot afford it, use bondex to seal the leakage. A 4kg tin costs about sh50,000.

 Q How much would a new roof cost?

The price of a new roof depends on the type of material you select, whether you are removing the old roof or not, the type of underlayment, the price of the permit and so on. 

For an average three-bedroom house, you might spend sh4m to sh6.5m. Always get at least three estimates if you believe the cost is high. 

However, if one person is cheaper than the other, ask the right questions about the type of materials being used and the reputation of the company supplying them. 

Just because it is cheaper, does not mean that it is better. Sometimes, the higher-priced contractor is the one you want to go with because of their reputation as a reliable contractor, or because the quality of the material they are using is good.