The environmental impact of construction is enormous. One reason we hope the popularity of prefab continues to grow is that it offers a solution to many problems caused by the building industry. While it might not solve all of them in the short term, experts and government agencies agree it can decrease the environmental impact of construction significantly and cancel out some of the shocking facts listed below.
Prefabrication is a construction method where structures or their main components are made in a factory, then shipped to the building site for assembly.
1. Construction is responsible for half of all non-renewable resources we consume.
This fact makes it one of the least sustainable industries in the world. However, it is vital to the modern economy. In the US, construction and the real estate industries together make up 17% of GDP.
2. In the UK, a quarter of all waste comes from construction.
The UK Green Building Council found the figure to be 109m tons. That’s three times more than all the nation’s households combined. The UK government is trying to eliminate waste going to landfills to zero by 2020 in a few ways, including more building with prefab.
3. Every year in the US, crews demolish 44,000 buildings and 270,000 homes.
Less than 30% of the debris is recycled, even though 90% is recyclable. According to the EPA, a 50,000ft² structure will generate 4,000 tons of waste if we include demolition. The UK’s Waste Reduction Action Programme estimates modular construction could reduce C&D waste by 90%.
4. Demolition accounts for more that 90% of construction and demolition (C&D) waste in the US.
Traditionally built structures are often useless once they outlive their purpose. Considering that one demolished house produces tons of debris, C&D recycling has a long way to go.
5. Up to 15% of materials delivered to build sites are not used.
Transport and weather damage on the way renders some of that percentage unusable. Once on site, building errors and overbuying send timber, roofing, and other materials to dumps. Vandalism, theft and weather conditions also cause waste.
6. The UK’s Environmental Agency responds to about 350 serious pollution incidents caused by construction every year.
The main areas are air, water, and noise pollution. For water, it’s the leading cause. Diesel engines, burning, and toxic materials at construction sites are just a few of the sources. Ongoing loud noise can cause stress and hearing loss for people while damaging natural habitats. Long building periods required for many projects aggravate the environmental impact of construction. Pollution reduction is one aspect where modular buildings, which builders can erect in weeks or days, have a distinct advantage.
7. In the US, 534 million tons of C&D debris was generated in 2014.
That’s more than twice the amount of municipal solid waste (MSW). According to the EPA, MSW “is comprised of various items Americans commonly throw away after being used. These items include packaging, food, yard trimmings, furniture, electronics, tires, and appliances.” MSW does not include industrial, hazardous or construction waste.
8. Building debris is an enormous problem in China, as the 2015 Shenzhen landslide demonstrated.
All the shocking facts about building are magnified in China, home to the largest construction industry. In 2015, a mountainous C&D waste dump collapsed, killing about 80 people and destroying 33 buildings. In 2016, China issued a directive that 30% of new projects will be built using prefab to reduce environmental damage while jolting steel demand.
9. Many US states and cities give significant tax exemptions for LEED-certified projects, which are much more costly to build.
To be clear, the cost of LEED, not the rebates, is a terrible fact. Nevada exempts construction materials that qualify for LEED building from local taxes. The Leadership in Energy and Environmental Design certification system is the most popular for green design around the world and is the closest thing to a global standard. However, a green project can carry a cost premium of up to 30%.
10. Buildings cause 39% of CO2 emissions in the US.
This is not strictly an environmental impact of construction itself, but a serious related problem. Eco-efficient retrofitting and green building for new structures are two ways homeowners and developers can bring that number down. Some forms of prefab, like modular containers, can help because they have high levels of thermal insulation.