Building a weather resistant home

“The engineer carried out an analysis of the foundation and recommended use of double layers of bricks on the ground floor with strong cement and sand mixtures. It also involved using stronger iron bars to support the columns up to ring beam level,” Mugabe recalls.

“At finishing level, because rain is unpredictable and changes direction all the time, I used tiles as skirtings after the final layer of external plastering so that it (rain) could not easily damage the house from directly hitting the lower parts of the outer wall,” he adds.

For the roof, Mugabe used thick and strong roofing timber, leaving very small spaces in between, after he had learnt of a scenario where one of his neighbours’ roofs had been blown away by wind. 

Understanding weather proof and weather resistance

Joseph Oryang, an engineer with Century Investors Limited, says weather proof is different from weather resistant. Whereas weather proof means your house is not affected in anyway by the harsh conditions a weather resistant home on the other hand means  your house can survive the prevailing weather. 

But when talking of a weather resistant home, you have to bear in mind the conditions of your locality such as Mugabe’s hilly area because sometimes you experience fairly strong winds, much as they may not be anywhere close to hurricanes experienced in countries such as the US.

A weather proof home, Oryang explains, is one that keeps out elements such as rain, wind, heat or even the cold. In Uganda, the problem is more of heat, much as it can be cold in certain seasons. A weather resistant house keeps warmth in the house when the outside is cold but should also keep the house cool when the outside is hot. It should also keep external sound out.

“When you live in a house with no ceiling but was roofed with iron sheets, you cannot do anything because of the noise. Such a house is not weather friendly and resistant. A weather resistant house starts from its construction and what you decide to use for the ceiling because it is dual purpose. The ceiling helps to keep out noise from rain hitting the roof but also keeps out the heat. It is why the interior of a ceiling is always hot when you enter it. The ceiling keeps the house cool when it is hot. At the same time, when the outside is cold, the heat trapped in the ceiling keeps the house warm,” Oryang explains.

Types of bricks used

When building walls, it is advisable to use hollow blocks that have air pockets. These pockets offer resistance to heat and sound transfer. They keep out the extreme heat better than solid blocks that would easily transfer it inside. If you touch the outside of a hollow block wall, it is hotter than the inside that will be relatively cool. 

“Hollow blocks are used not just for saving construction costs or making the walls lighter but they also regulate or act as temperature transfer barriers. A hollow block wall also keeps out sound better than a solid wall. When you use solid bricks such as those baked from clay or soil, they tend to be more porous than blocks much as there are some instances where they (solid bricks) also do a fairly good job. Hollow blocks remain a better choice because of air pockets,” Oryang adds.

House floors

A weather resistant house does not only focus on the walls but it pays attention to how you set up your foundation and the floors.

Ibrahim Kajjoba, a site technician advises that using averagely big hardcore stones underneath, followed by a concrete slab on top, in some cases, helps form a barrier or an air circulation pocket because there will always be air between the stones and the ground, which might be hot or cold, and the floor of the house.

“When you walk on a tiled floor during the rainy season, it tends to be cold. And in the extreme dry season, you will feel the tiled floor is cool when you walk on it, unlike a cement floor that absorbs and keeps heat. If you use polyvinyl chloride (PVC) tiles, even when the outside weather is cold, your tiles will remain warm,” Kajjoba says.

Finishing

When it comes to finishing, Oryang and Kajjoba agree that the floors and ceiling are what is important. If you have a ceiling that is made of a wire mesh and plastered, the alternative could be using soft boards as the only two options to keep out the heat well. If you opt for something such as hard plywood that has no air pores to let your house cool, it may not serve the purpose of a weather resistant house well.

If you need cool floors, the recommended tiles are those made from ceramic or porcelain. Unlike cement, tiles are able to keep your home cool by not retaining any heat. However, different colours have different levels of heat retention, for example dull floor tiles such as black tend to absorb and retain more heat than brighter colours such as white that reflect heat.

Areas such as your kitchen, living room and any entertaining areas are all fantastic places to tile, as they will have the maximum effect in helping to keep the temperature in your place down.

The same colour factor affects the roof as well. Most roofing materials are by design, resistant to water and wind. However, different materials react differently to different weather elements. While iron roofing may be more affordable and a popular choice for average Ugandans, it may not be the best defense against heat or strong winds.

Tile roofing may be a little bit more expensive, but it offers a longer lifespan and more resistance to weather elements.  Also the quality of the materials is a major determining factor for instance when the roof is ageing or damaged they will not be of much help when it rains heavily. 

“When doing outside plastering, you need to use a rich mix of sand and cement. Paint paste can go on top of the plaster. You could also use paints such as weather guard because it resists and withstands any weather changes or conditions and lasts longer. When it gets dirty, you can easily wash off the dirt, unlike some other paints where you will have no choice but to repaint the house when it gets dirty,” Oryang advises.

Like Mugabe, you can also use skirtings around the house on the outside after plastering. It could be either with slates or stones or tiles cut to the required height. Sometimes the wear from the rain and water levels from the house’s surface is quite high.  

The aspect of windows

The other aspect that makes the house weather friendly are the windows. Much as it is somewhat expensive, Oryang says there is an option of using double-glazing. Double glazing is where one uses two layers of glass instead of one; the outer layer, then a pocket of air in the middle, and the inner layer.

When you have double-glazed windows, heat transfer is better because it keeps the warmth inside the house when you need it but also keeps out the heat when you need the house interior cool. In common circumstances, these windows are, Oryang observes, used in more houses as sound barriers than heat barriers.

“Double-glazed windows work best when your house is near the road that is a source of continuous sound and noise. Using double-glazed aluminum on windows and hollow blocks on the walls will greatly and significantly reduce sound levels,” Oryang says.

Depending on where you buy them, a single glazed aluminum window costs approximately Shs400,000 per square metre while a double glazed window costs approximately Shs500,000 per square metre.