between the BaU scheme and the as-built performance of the P-DfMA scheme.
Reducing the number of radiators from 10 to just one would reduce carbon by 10.7 kgCO2/m2.Reducing the size of the photovoltaic array from 24 to 12 units would reduce carbon by 12 kgCO2/m2.
All the above items added up together would mean just a reduction of around 4.7 kgCO2/m2, mainly due to the simplification of the heating and photovoltaic systems.Compared to a residential LETI 2020 (Band C) target building (A-C) with a total embodied carbon of 675 kgCO2/m2, that is equivalent to just 0.7% reduction in carbon..Comparison of embodied carbon (A-C) between a baseline residential building based on LETI Band C and same building with Passivhaus characteristics.
The adoption of the above Passivhaus standard does not have a substantial impact on the embodied carbon compared to a standard residential building.The adoption of Passivhaus does not prevent the incorporation of additional strategies to reduce embodied carbon and all designs retain the potential to achieve low embodied carbon performance if it is part of the design intent.. Further potential benefits from Passivhaus arise from the compact shape and the use of timber, although full life cycle analysis is required to quantify this.
The compact shape is predicted to reduce the absolute quantity of materials whilst timber is a material with low embodied carbon which can be ultra-low depending on its end-of-life treatment..
Timber shows its maximum potential if it can be continuously reused at the end of a buildings’ lifecycle.The pre-manufactured components of platform construction (P-DfMA) systems are specifically designed to be standardised and mass-produced by a wide supply chain, like the mechanical components of a car, to deliver the greatest possible factory efficiency and economies of scale..
The components can be easily transported and moved, and they fit together quickly and simply on site with the least amount of handling.Platform construction systems are designed to be flexible and customisable to avoid limiting design freedom and allow massing, form and aesthetic treatments to be considered on a plot-specific basis.. Driving value with MMC and P-DfMA.
Construction platforms are an example of an approach to DfMA that relies on both off-site and on-site construction works, bringing the best aspects of both.The division of fabrication and assembly tasks has been carefully considered to maximise the efficiency of both factory prefabrication and on-site assembly.