Developers turn to prefab technology to cut down costs

By: Allan Olingo

For a long time the country’s construction sector has been stuck to the brick-and-mortar method of building, but the acute housing shortage, coupled with the rising cost of construction, is driving developers to embrace other options and technologies.

Moke Gardens in Athi River has already embraced the use of prefab technology in its second phase in order to take advantage of the benefits it offers.

Mr Harun Nyamboki, the man behind the project, says the houses, which are assembled, can be ready in less than six months, depending on the size and style one chooses.

“I looked at the construction timeline, and with the huge demand for housing, saw it as the best way to go. I will be able to deliver houses to the market in a record six months, and of good quality too,” Mr Nyamboki says.

In August, a Chinese firm set up a Sh3 billion factory in Kitengela to manufacture prefabricated building materials. During the launch, Boleyn Magic Wall Ltd said it would manufacture wall panels, half slabs, staircases, hollow core slabs for flooring and roofing, columns and pressurised beams. The factory can produce housing panels and materials to put up 20,000 units a year.

At Moke Gardens, the prefabricated components are manufactured offsite. The process involves casting concrete on a steel pallet, after which it is cured in a controlled chamber. The panels that for the walls, slabs, roofing and staircases are brought in from the factory and assembled on site to form a skeleton house.

Before this, however, a foundation laid. But it is not dug as is the norm; rather, it is filled with specially compressed soil before a slab is moulded onto it.

Mr Nyamboki says the technology is appropriate not just for maisonettes, but can be used in large-scale developments.

“I am confident that my customers will be happy with the product I am offering, given its superior technology. With the high demand for housing, I am excited that I will be able to meet the market expectations while saving on the opportunity costs,” Mr Nyamboki enthuses.

REDUCED COSTS

Meanwhile, Boleyn managing director Jack Liu says that they expect to bring down the cost of building a home by up to 30 per cent.

“This technology supports a reduction in construction costs. It’s for those developers looking for ways to bridge the housing gap in the country,” Mr Liu says.

“When you look at the quality of these houses, we are at par with other technologies because the precast concrete is manufactured in a controlled environment. This allows us to standardise the mixing, placement and curing,” he adds.

Prefab technology isn’t entirely new as it has been used extensively in Europe, Egypt, South Africa and the Middle East in large-scale government housing projects.

According to experts in the property industry, prefab technology is appropriate for use in the country because of its climatic conditions and the rarity of natural disasters like earthquakes. The technology also cuts down on labour costs and construction period by more than 50 per cent.

“A good example is Thika Road. All those barriers you see on this road were made using prefabricated technology. See how it has turned out,” Moses Muriuki, a structural engineer says.

He adds that the technique can be used to construct high-rise buildings because it is strong and durable.

Mr Daniel Ojijo, the chief executive of Mentor Holdings, says the technology is a welcome addition to the sector because of its immense benefits to developers.

“We are looking at a five per cent reduction in capital expenditure. Developers have been grappling with lengthy construction periods of up to 24 months. When you look at the opportunity costs lost in these timelines, you notice the savings the technology brings,” Mr Ojijo says.

Precast concrete technology is touted as the likely replacement for conventional building techniques. Brick-and-mortar construction has become too expensive and time consuming, forcing developers to absorb losses and additional financial costs.

Mr Michael Njahi, a quantity surveyor, says that the use of the brick-and-mortar method has contributed significantly to the high prices of houses, mostly because of the many inputs it requires.

“It is notable that labour alone marks up the units’ prices by 15 per cent. When you reduce this cost through alternative technology, you see the first big drop,” he says.

“The only major cost I foresee with this technology might be the foundation and the roofing. The foundation will be largely because of the terrain. If it’s on a slope, then you will have to do a lot of filling to level it. The roofing will affect those who choose funky designs.”

The other expensive element is the cost of the slabs. On average, constructing slabs for a three-bedroom house will cost not less than Sh800,000 in an area like Athi River, mostly because of the black cotton soil, whose excavation cost averages Sh150,000. This pushes your overall costs upwards.

CONTROLLED CONDITIONS

In 2012, the National Housing Corporation (NHC) announced that it was building an expanded polystyrene panels factory in a bid to promote affordable housing, but uptake has been slow. The factory can produce more than 126,000 polystyrene panels annually.

NHC managing director Andrew Saisi attributed the slow uptake to misinformation about the technology.

“We have not seen great publicity with regard to this technology. This has made the market slow to embrace it as most of their questions remain unanswered. We have also seen a challenge with professionals who understand this technology,” Mr Saisi said.

Apart from NHC, Koto Housing is another firm that has been at the forefront in the push for prefab housing technology. The firm says it can build a three-bedroom unit at a cost of Sh2 million in less than a month using the technology, while a brick-and-mortar house of a similar size costs Sh6 million, depending on the location.

International Green Structures is also putting up a prefab manufacturing facility in Thika. In October last year, the firm said it could build a Sh800,000 two-bedroom house made of compressed prefab materials.

Apart from the pre-cast options, there are also other prefab options, such as the ready-made steel houses produced by Mabati Rolling Mills, which target low-income earners

Developers are also beginning to appreciate prefabricated timber houses, with the Economic Housing Group capable of putting together a two-bedroom house in less than two months.

There has also been growing use of the structural insulated panels (SIPs), with the first phase of Jamii Bora in Kaputei, Kajiado Country, having used this technology. This saw a 50 per cent drop in price to Sh4.9 million instead of the Sh10 million it would have cost using brick-and-mortar technology.

The SIPs are manufactured in controlled conditions by sandwiching a core of rigid foam plastic insulation between two structural skins of oriented strand boards. The panels can be used for floors, walls, and roofs for residential and light commercial buildings.

Meanwhile, Elsek Construction, which specialises in light steel construction technology, has been promoting the use of fibre cement and galvanizing steel in construction. The technology uses walls made of cement, stone and glue chemical for strength.

SOURCE: DAILY NATION