Construction sites could be defined as locations where finished assets are built.
Adding insultation (rockwool) thickness in floor and ceiling from 190mm to 370mm of rockwool would increase carbon by 6 kgCO2/m2.Reducing the boiler size from a 15kw electric boiler to a 3kw boiler would reduce carbon by 1.69 kgCO2/m2.
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.In short, we want construction sites to be more like factories.. Off-site and modular construction: are factories really all that great?.
Prefabrication in factories (off-site construction) is often thought of as a panacea, a sure-fire way for construction sites to achieve greater productivity.However, factories can also be run inefficiently, and if traditional construction methods are simply shifted into a factory setting, the benefits of MMC can be diluted or lost..
In some cases, building off-site in a factory may even be less efficient than on-site construction.For example, prefabricated 3D modules (used in modular construction) involve many additional costs compared to conventional build.