Housing and construction sectors' environmental impact explained
Housing and construction sectors’ environmental impact
Housing and construction account for 47% of global CO2 emissions
The latest report by United Nation’s “Global Alliance for Buildings and Construction” found that housing sector’s environmental impact is the largest in the world, making 37%* of world total CO2 emissions in 2020. Emissions in 2020 fell slightly in comparison to the previous year (1% less than the 38% in 2019), but only due to the Covid pandemic related supply chain and economic difficulties. The biggest problem though is that the overall emissions from housing are expected to double in total footprint by 2060.
*It is important to note that 37% of global CO2 emissions comes from residential and commercial housing only. This does not include the overall construction sector with infrastructure and industrial construction, which adds an extra 10% to global yearly CO2 emissions.
Construction uses 50% of the world’s resources and fills up 33% of our landfills
Housing and infrastructure require huge amounts of natural resources. Approximately 50% of all extracted resources are consumed by the construction sector. This is strongly led by the extraction of sand, gravel and limestone which are used for fillings, building infrastructure and making cement.
The amount of construction waste from total amount of waste in landfills differs significantly from country to country, ranging from 13% – 60%. For example, in Finland it is 13%, Canada 27% and Israel 60%. On average, 1/3 of all waste from construction – this is roughly also the average of the EU where construction contributes approximately 35% to the total waste generation.
There are two types of construction waste:
- Waste from new construction projects. Up to 30% of new materials can end up at a landfill.
- Waste from demolition. The majority is landfilled (exception is steel of which 98% is recycled).
The amount of construction waste which is being recycled is increasing in wealthier countries (there is little data on other regions). Approximately 50% of construction waste was recycled in the EU in 2018. However, it is important to note that the goal set in 2008 by the Waste Framework Directive 2008/98/EC aimed to have 70% of construction and demolition waste recycled by 2020. The process is slow.
Major problems in the housing sector
1. Inefficient buildings
The construction industry is based on delivering buildings on time within budget. Here’s the logic:
Fast + Good = Expensive
Cheap + Good = Slow
FAST + CHEAP = IMPOSSIBLE (at the moment) = ENERGY INEFFICIENT
That’s why, as an example, approximately 75% of the current buildings in the EU are energy inefficient. However, investment in energy efficiency in the form of renovation of old buildings has been climbing. The global public investment into housing energy efficiency reached approximately US$180 billion in 2020, up from $160 billion in 2019, whereas the majority of this total investment has come for the EU for old buildings’ renovation. In addition, new buildings in the EU are rather energy efficient due to improved technologies and at large, due to non-voluntary policies and codes.
2. Policy making
The challenges to reaching a net zero, energy-efficient, resilient buildings and construction sector are considerable. It is expected that by 2030, 82% of the world population will be living in countries without any building energy codes or only voluntary codes.11
Policies and incentives are essential for large scale change. Otherwise, the FAST + CHEAP = INEFFICIENT option will prevail more sustainable practices.
3. Our wants and needs
There are more people who live alone and/or expect to have a good standard of living, which is fair enough, as we all want to enjoy life. This means more built m2-s to satisfy our needs for residential as well as non-residential housing space.
The problem is when policies for energy efficiency are applied, owning more space will become more expensive and possibly cannot be reached by many. This does not support social sustainability, which is a part of the 3 pillars of overall sustainability.
4. Money and power
We shouldn’t forget that the construction sector is fuel for growth and for our governments’ budget. Construction also allows governments to show what they have done as the built environment is visually “there” that all the voters can see. Yes again, fair enough, we all want good roads and nice public spaces. The important thing is to make sure that the strategy wouldn’t be FAST + CHEAP as otherwise we create more future problems than we solve.
Lowering the overall impact
There are two ways to lower the impact of housing on the environment: REDUCE AND REUSE.
REDUCE
- Design (energy and resource efficiency)
- Whole life-cycle approach for building
- Use of quality, low to zero building materials
- Reduction of material waste
- Use of smart solutions to improve energy efficiency
- Use of renewable energy
REUSE
- Design for deconstruction
- Improve existing buildings (make existing buildings energy efficient)
- Use of recycled materials
Lowering the individual impact
The majority of large-scale changes in the housing sector are driven by policies and in some cases public incentives. Green policies (the European Green deal, the Green Agenda in the UK and Australia and equivalents) and the energy crises that started in 2021 has given a big push for policies targeted at existing and new buildings’ energy efficiency.
The majority of fundamental changes in the housing sector come from decision makers who sit far from a home owner. However, it does not mean that we should simply wait for the changes to happen. We can and should make individual and group decision to REDUCE and REUSE. Undeniably, this is all subject to being able to do so. The cost of construction is high and being aware of sustainable choices and wanting to have an energy efficient home (accompanied by low energy bills) is out of reach for many. This takes us back to policy making and incentives. Nonetheless, here are the perhaps too obvious answers to what we could do:
- Living in an old house? Renovate, insulate, ventilate, evaluate different materials and energy systems. The cheapest options usually turn out the be the most expensive.
- Building a new house? Work with architects and engineers who think of sustainable design, optimised space and would recommend different materials for making the best price/quality decisions (the cheapest will cost more in the medium and long term).
- Buying a new home from a developer? Make sure the house is properly built. Sometimes and in some places trusting the developer or checking the background of the developer is enough. Sometimes, an opinion of a specialist could be a good idea. It is also important not to forget that houses are like cars, they need regular maintenance.
- Living in a residential building that needs improvements? Join the management of the house and advocate for change and improvements. Best case scenario, a well renovated building can save up to 80% of the total emissions.