Prefabricated steel houses come sleek, sturdy and cheap

Exterior and interior of the steel prefab
Exterior and interior of the steel prefab house. PHOTO | FILE 

Inside and out, the prefabricated steel house is modern, lined with lime green and cream walls, lots of artworks, and dotted with tasteful furniture.

This is the steel-structured prefabricated house designed by Castle and Gardens, an interior design company in partnership with Eco-Steel Africa, a steel construction firm that deals with prefabs, exhibited at the Ideal Interiors Expo last year.

The flooring is pergo and the walls lined with gypsum board. This is the kind of house that can be delivered on a truck to any location and turned into a perfect home within a short time.

Assembled at factory

Prefab building technologies have cut the time used to construct a single house by half.

Gary McIntyre, Eco-Steel Africa managing director, said steel prefabricated structures are gaining popularity as demand for affordable and timely houses rise. The prefabs are especially popular among people who want affordable housing and warehouses as they are easy to assemble and complete.

The company uses light gauge steel structures to make panels, which are then assembled together at the factory with bolts to make the structure of the house.

“These are semi-permanent structures perfect for remote areas as they have low impact on the ground and use steel columns raised above ground,” said Mr McIntyre.

The light gauge structures save developers up to 20 per cent of the construction cost as compared to conventional building.

“This was our first project of prefabricated steel structure and it was a success as previously we dealt with steel containers,” said Risley Kavu, an interior designer at Castle and Gardens.

Steel prefabs can either be temporary or permanent depending on the intended use. It can be dismantled and set up in another location.

If you’re planning to build a permanent prefab house, then it has to start with a foundation made of concrete. For a temporary house, the level of the house is raised using steel structure. The prefabs are custom-designed according to the given measurements.

Zero errors

“We have zero errors when it comes to getting the measurements right as every steel panel has to fit correctly with the other panels,” said Mr Kavu.

The steel structure, including the walls and the roof, costs Sh600,000 onwards depending on the size of the house.

Low-entry houses could cost between Sh30,000 and Sh35,000 per square meter and an average of Sh60,000 per square meter for high-end housing. The prefab show house at the expo was a one-bedroom house with a kitchenette, living room, toilet and bathroom and costs Sh1.5 million without the proper fixtures and fittings in the toilet and bathroom, windows or doors.

How it is done

For prefab houses, the steel frame is done at the warehouse, reducing building time and minimising the space and equipment required on the site. After the structure has been put together, the gypsum board panels are drilled onto the structure and adhesive is used to seal the joints.

“We use waterproof gypsum boards for the exterior of the house that can withstand all weather patterns including rain,” said Mr Kavu.

He said plumbing works are done well to avoid leakage that can damage the gypsum board. The kitchen and bathrooms have waterproof gypsum board and can be fitted with ceramic tiles.

Mr Kavu recommends pergo flooring as it is sound absorbing and blends well with the gypsum board.

As for roofing, any material can be used, either iron sheets or tiles depending on one’s preference.

Aluminium frames are used for the window frames. Various finishing touches are done on the walls such as cladding using gypsum board, fibre cement board or canvas for those opting for a tented look. When finished they look like regular houses, you won’t see a prefab.

Architects and engineers are rooting for steel houses, arguing that they are stronger than those made out of stone due to the firm structure.