An innovative concrete block with embedded eco-friendly insulation is being developed at the University of Malta with a view to mass-producing the energy-efficient building material by 2024.
In a move from “grey to green”, the idea is to embed a durable, degradable bioplastic into the block for insulation, instead of the widely used add-on cladding layer, derived from fossil fuel sources.
The end result will be a product that is compliant with zero-energy buildings, explained architect and civil engineer Luca Caruso, who is conducting the research.
The study is “taking an ecological leap” from the use of conventional petrochemical-based materials, such as polyurethane foam, to bioplastics, with the ultimate goal being a lower overall environmental impact throughout the concrete blocks’ life cycle.
Bioplastics are composed of natural materials, such as plant-based oil, and have similar – or even better – mechanical and thermal properties, as well as being degradable, explained the researcher from the university’s Department of Environmental Design, within the Faculty for the Built Environment.
The traditional concrete block has a high thermal conductivity value, meaning it does not retain heat inside in winter and protects from the scorching sun in summer, Caruso said.
Apart from lowering energy bills by reducing the need for heating and cooling, leading to a lower national consumption of LPG and CO2 emissions, the innovative insulation also has acoustic properties, increasing soundproofing.
The researchers also aim to reduce the standard thickness of the block from 23cm to 20cm, including insulation, without compromising its structural integrity while increasing indoor space.
Practical advantages expected from the product include more comfortable indoor spaces also in terms of temperature and humidity levels, Caruso said.
His PH.d study builds on already established results for the first prototypes of a composite Concrete Masonry Unit (CMU), with embedded polyurethane insulation, called the Double C Block.
This is already being used to erect walls at the university’s state-of-the-art Sustainable Living Complex, set to be completed in 2023.
“We are not just looking at when the block in laid on site, but also how it can be reused by crushing it and reproducing new concrete,” he said.
The project is financed by the Malta Council for Science and Technology and has already partnered with concrete producer, Attard Bros Group, to “make it real”.
The research is looking for an economical way to manufacture the blocks.
So far, it is a “struggle” to churn out 500 in two weeks through a handmade process as opposed to the 2,000 traditional blocks that are produced daily.
The innovative blocks should be less expensive than their traditional counterparts because they would not require the additional insulation cladding.