Mechanical engineer presents solution to reduce cost of construction
Monday, October 28, 2019
Constructors join the interlock bricks in Kigali. Photos by Joan Mbabazi.

Gaitan Rucyahana is a mechanical engineer who has always wanted to introduce innovation that would lower housing prices in Rwanda.

He had no doubt that expensive housing materials were the leading cause of the high-cost housing prices.

Having seen the concept of constructing using interlock bricks in Mauritius, he wanted to try it back home.

 He endeavored to make a machine to produce interlock bricks. This took him about 10 days.

Gaitan Rucyahana explains how the machine works.

Early this year, he started up a business in Remera where produces bricks. At first, Rwandans didn’t embrace the idea as few had seen the concept used before, however, those that have used the bricks have recommended other people to him.

"Interlocking bricks are bricks that have been designed to fit into each other. Each brick has a protrusion at one end which enables them to fit perfectly. Each brick is designed to have a vertical hole which means, not only saving on the amount of the materials used in it is production, but also allowing metal rods to be inserted, or cement to be filled in, to increase its structural strength during construction,” Rucyahana said.

He added, these bricks can be made by mixing sand and cement or selected soil with very little cement then compressed using a mechanical press or hydraulic pressure.

A house _under construction using interlock bricks

In the beginning, Rucyahana could make like 250 bricks a day. However, in about a month, he made a better machine which improved the bricks from 250 to 500 per day.

The mechanical engineer explained that interlock bricks are easy to use and save time.

When it comes to construction, the lesser the time taken, the lesser the costs. If four technicians were to take about three days using interlock bricks, this would need five or six days using the other usual bricks.

He noted that, today, the interlocking bricks system is internationally recognized for its role in the construction industry. Interlocking systems may have the answers to some construction issues than using conventional materials.

He further noted that interlock bricks are efficient, require a short time for the project completion, cost-saving, have a comfortable interior, and yet heat doesn’t go through the bricks easily.

"When constructing using plain bricks, a lot of cement in the mortar is used, more cement while plastering the house and a lot of time spent while aligning the bricks, which is not with interlock bricks,” the mechanical expert noted.

He also stressed that the interlocking bricks don’t need a mortar, they are simple to use and they don’t require intensive labor to use. Anyone can use this kind of bricks to construct provided they are given a simple training of about five days.

Rucyahana pointed out that, an average house of about 10 meters by 7, can take a maximum of three days while using the interlock bricks, yet with other bricks, it would double the days.

He has been able to construct about 10 houses in Kigali using the interlocking bricks, with hopes to further rollout use of the concept the idea to different areas.

If a person buys our bricks, we give them a technician that shows other engineers on how to use the bricks, he noted.

He said; "When a client approaches us on buying the bricks that will be enough for the whole house, we first visit their site and estimate the surface area in square meters, then we know how many of these go into one square meter and multiply them by the number of square meters the house is likely to occupy.”

Rucyahana sells one square meter of the interlock bricks at Rwf 6,000, which he says is cheaper than the usual concrete bricks as they cost about Rwf 8,500 and clay bricks that go for Rwf 16,740 per square meter. When you compare the interlock bricks with the usual bricks, there is a difference of 30 percent.

He has employed about six permanent workers and four technicians who are deployed on sites whenever there are clients who need bricks.

Rucyahana said that the interlock bricks are made with just sand or cement and water. In about 14 days, they are ready to be used. The more they stay, the stronger they become. In a day, if using one machine, the mechanical expert can make about 500 bricks, which is about 12 square meters (this can make a wall of about six meters long to two meters’ height).

One of the challenges he faces is that people still have a mindset that what they were used of is better.

Another challenge is posed by some constructors want to take more time at the construction sites so that they are paid more money, they are hesitant advise their clients on the use interlock bricks as it speeds up the construction process.

He said, transportation costs are a bit high.  A Fuso truck takes about 1500 bricks, for a distance of 20 kilometers, it would cost about Rwf 50,000 per route.

It is for this reason that Rucyahana looks forward to starting a mobile production workshop where he and his workers go on a construction site with their machines, and make the bricks from there so that transport costs are saved.

He said that he is keen on expanding reach of his firm as well as improving marketing skills as more awareness is needed.

A close view of a constructed house with interlock bricks

A close view of a constructed house with interlock bricks

These are some of the bricks that are made at Rucyahana's work shop. They have two holes that enable them  to fit in each other perfectly

Some of Rucyahana's workers moving out a brick from the machine to dry

editor@newtimesrwanda.com