What is the best type of roof for Malaysian houses? There is No answer to this question. Every type of roofing material has its advantages and disadvantages.
 |
| Untreated slab with cracks and chipped surface. |
The most commonly used roofing is the concrete roof tile. Some use clay tile, metal roofing sheet or aluminium roofing sheet. There are also houses having flat concrete slab roof. This type of roof is more visible in Europe and USA than in Malaysia.
My house used a combination of concrete slab roof and glazed clay tiles. The Architect designed and proposed the concrete slab roof due to construction issues. This portion of the roof is waterproof and does not leak even during extreme thunderstorm.
 |
| Mixing cement with white clay(lime) and sand for plastering |
The tropical weather of Malaysia is unkind to concrete roof. The sudden change in temperature from very hot sun to heavy rain caused fine cracks and chipping of the plastered surface of the concrete slab. If the cracks and surface chippings are not patch regularly, the waterproof coating will wear off and eventually leakage will appear.
 |
| Re-plastered surface |
In order to avoid the problem of regular patching, I use a coating of polymer sealant. This material can grout the cracks and level the chipped off surface.
This is my biggest DIY project spreading over a period of nine months. I worked in stages and not more than three (3) hours per day.
 |
| Partly cleaned slab |
First, I water jet the floor slab and the beams to remove dirt and fungus. Then, re-plaster the cracks and the worn out surface with a mixture of cement, white clay (lime) and fine sand. Let the re-plastering cure and set in for about a month. Some plaster may not stick well and peeled off. I re-do the peeled off part until the surface is completely even.
 |
| Clean the slab with pressure water jet |
The surface must be totally clean and dry before applying the polymer sealant. The re-plastered surface is water jet again and allow to dry for a couple of days.
The “Pentens” polymer sealant can be applied on the surface by using a paint roller or a big broom with soft bristle. This is a water-based sealant. If the compound is too thick, add a bit of water but not more than 20% by content, for easier application.
 |
| Pantens Coating Compound. This 20kg pail cost RM250.00. |
 |
| Coating done in stages This coated surface is easy to clean with a wet mop. This compound has low absorbent for heat and lower the indoor temperature. Do not use any sharp object or metal on the surface. This is like Epoxy coating. It can scratch the coating easily. |
 |
| One third of the slab completed with coating |
Apply two coats of the sealant with three-hour interval. Do not step on the coated surface, even if you feel it is dry. The sealant takes about twenty four hours to adhere firmly to the concrete surface. Always leave some space, a walking lane, for you to walk while applying the coating without stepping on it. The space is also required for applying the second coating. The walking lane can be coated later, preferably after three days, by then you can walk on the already coated surface.
 |
| The entire concrete slab is coated. |
The tools required are:-
 |
| Some of the tools required |
A pail for water, a pair of cotton gloves, a scrapper, a paint roller, a paint mixing tray, a soft bristle broom, two paint brushes, a big picnic umbrella and a pressure water cleaner.
30 kg of Pentens sealant was used to coat the entire surface. Total cost of the sealant is RM375.00(USD125.00)
