Future of Construction.org:
A central platform to exchange best practices and ideas guiding the infrastructure and urban development industry in its transformation, and helping it to address its key challenges.
Winner of 3D Printed “Hempstone” House Can Replace Cement for Greenhouse Gas Reduction 3DPrint.com July 16, 2015 “Chad Knutsen leads a team that has proposed to the MIT Climate CoLab a project that will reduce worldwide CO2emissions by 7-8% with the help of 3D printing. How? Knutsen is proposing a hempstone construction project as a replacement for cement. All “hempcrete”/”hempstone,” or hemp plastic or resin components, will be 3D printed in small manageable blocks in a skeletal form applying minimal material.
You can use stack these blocks together forming the body of the house, for example, and the blocks will include space for utilities and wiring in their design. An added benefit is that hemp can be grown and harvested worldwide, which can reverse damaging effects. (The US is the only advanced industrial nation that doesn’t allow industrial hemp farms.) After a few years, the hempcrete petrifies — evolving from plant into stone –which is pretty incredible when you think about the fact that this means more CO2will be absorbed than released during construction and petrification processes.
Knutsen’s team wants to build a home with hempstone, which is made from micronized limestone, and specially milled refined and very strong hemp fibers. The plan is to use a proprietary technology that breaks down materials and teases them apart along natural structural boundaries. (This utilizes resonant frequency and negative air pressure instead of heat and friction.) The hempstone will be poured into lightweight and easily shipped hemp resin or plastic 3D printed frames to create the house, which will also have other ecological features as well. The team proposes to outfit the house (rough sketch of house seen below) with other new non-commercialized environmental technologies, so they can give inventors a chance to showcase their innovations as part of the future hempstone house.”
MIT’s Mediated Matter Lab Develops Mobile, Autonomous Robot and 3D Prints Large Dome Structure in Hours April 27, 2017 “The researchers reported in their paper that the dome structure, at 13.5 hours, is the fastest building ever to be 3D printed by a mobile robot; it’s also the largest, measuring 14.6 meters across.”
Affordable housing: new construction technology bringing costs down — BY SIMON ARDONCEAU—
“1. ‘Cast in situ’ housing units
One South African-based firm has introduced an innovative alternative construction system that delivers concrete housing units that are cast in situ, using patented plastic-moulded formwork and a special mix of aerated concrete. We have estimated the current average cost per square metre for a basic housing unit to be USD 184 in the South African market.
- Load-bearing steel frame units. Butterfly Housing
Another manufacturer has introduced a modular construction system, in the SSA market, which combines the use of a load-bearing steel building frame with stone or insulated fibre cement walls. With the structure in place, building services such as plumbing and electrical systems, fittings and finishes can be installed separately, maintaining flexibility, and allowing for hassle-free changes to different structural components over time.
- Prefabricated modular units
In Kenya, some of the innovative solutions provided by companies in the local market include prefabricated housing units. The construction process involves the on-site assembly of standard sections of a house that were manufactured in a factory and then transported onto site. Prefabricated construction methods are estimated to reduce construction costs by 30% and according to the manufacturer, the price for a basic two-bedroom prefabricated housing unit in Kenya can cost about USD $167.”
Affordable housing: Public Private Partnerships driving progress— BY SIMON ARDONCEAU— PPPs are essentially, strategic joint-venture arrangements between public institutions and the private sector, in which both parties collaborate in the delivery of various assets or public services based on a formal agreement by both parties. These arrangements generally seek to bolster efficiency and quality while lowering the cost of public projects by sharing expertise and resources in the most optimal manner, minimising risk and maximising returns for both parties.
According to the World Bank, PPPs can take on a variety of permutations, depending on the level of risk and involvement assumed by the private party. On the one hand, low private risk and involvement would entail public retention and operation of assets, whereas high private risk and involvement is characterised by the private sector retaining ownership and operating assets, often with a pre-defined exit strategy for the private party.”
Affordable housing: opportunities for the private sector— BY SIMON ARDONCEAU—
Some of the challenges that investors have been facing thus far include:
- The absence of data (on housing quality, prices, land ownership, property transactions)
- The high cost of land and infrastructure
- The costs of housing construction along the production line
- The barely inexistent mortgage markets (in order to enable an affordable mortgage for target purchases and secure stable interest rates)
“In 2017, one of the largest banks in South Africa accepted the affordable housing challenge. The company invested approximately USD 10 million into an affordable housing project in Cape Town, developed by a private developer on behalf of a social housing association. The construction of the first phase began in 2015, this development will add 630 dwelling units to the affordable housing market, which are already fully booked. Thanks to a PPP structure, both the bank and the developer were assisted by the Western Cape Provincial Government and the Social Housing Regulatory Authority. The public sector support included a land grant and subsidies reserved for the development of affordable housing projects. Further, the housing units delivered were sustainably built with a high level of resource efficiency. As a result, this program is the first affordable housing development in South Africa to be preliminary certified “EDGE Green Building” by the Green Building Council of South Africa.”
WEAVING A HOME – ABEER SEIKALY Solar Fabric on hard plastic tubing collects rainwater and stores power in a battery. Cool-looking, collapsible refugee domes that provide warm showers and indoor lighting.
