The road to Net Zero in Building Repairs

There are currently no specific targets for reducing carbon emissions in building materials and no standard methods to measure the environmental impact of these materials. This means that the progress in developing low carbon alternatives to some of the more traditional materials and methods used in building and construction has been slow. The alternatives that have been developed tend to be higher in cost and often in scarce supply compared to standard materials, meaning take up is low.

This also means there has been little incentive for the insurance sector to allow the specification of lower carbon materials in claims for building repairs. This is completely understandable given the costs this could incur and the impact this could have on premiums but clearly a way forward needs to be found that will require collaboration across the industry as a whole.

The way the carbon footprint of the products used in property construction tends to be measured is by looking at the embodied carbon. This is the total carbon emissions of all building materials and products and the construction involved to put them together. It accounts for about 20% of the carbon emissions from the building sector.

This is just one factor when considering carbon emissions - there is the risk of toxic emission release, as well as the carbon cost of extracting the raw material, processing it, transport to the place of manufacture, manufacturing the final product, transporting to site, installing the product, wastage on site and disposal when the building is demolished.

Taking timber as an example, all wood has low embodied carbon, is sustainable, economic and has many uses but the harvesting, transportation and processing of the timber uses a lot of energy, creating high carbon emissions. Once in a building, the timber acts as a carbon ‘sink’ until the end of its life and if it is disposed of by burning (a common outcome), all the carbon (50% of the material) is released.

So there are many factors to consider when assessing the carbon impact of products but while progress is slow in low carbon alternatives, we are seeing some promising developments in the materials with the biggest carbon footprints in construction:

Concrete

Concrete is responsible for 1.5% of UK CO2 emissions (7.3M tonnes). However, the Low Carbon Concrete Routemap[i], sets out three decarbonisation routes to 2050. Even under the most modest route, emissions are expected to fall from 10m tonnes CO2e in 2022 to 5m tonnes in 2035.

Cement

Cement is also a heavy emitter of carbon as every tonne of Ordinary Portland Cement (OPC) emits 622kg of Co2.  The alternative is LC3 based on a blend of limestone and calcined clay. LC3 can reduce CO2 emissions by up to 40% and save up to 25% of costs in production. By reducing the use of OPC it is calculated that CO2 emissions will reduce by 2%.

Plasterboard

Plasterboard is commonly used in insurance repairs but was responsible for 3.5%[ii] of the UK’s annual emissions in 2017. It is energy intensive to manufacture and an estimated 300,000 tonnes of board waste a year is generated a year.  Alternatives are being tested including a carbon-absorbing, sustainable and completely biodegradable plasterboard called Breathaboard. Until this becomes widely available, reducing the carbon footprint of plasterboard currently comes down to specifying lightweight products and eliminating waste material.  

Paint

Most water-based gloss paints claim have at least 30% lower embodied carbon[iii] and contain 72% lower Volatile Organic Compounds (VOCs) than solvent based paints. However, while VOCs are harmful to the environment, solvent based paints are still considered superior for exterior use, resulting in less painting during the lifetime of a building and fewer emissions.

In the meantime, new paints coming on to the market claim to have 90% less embodied carbon than trade paints but also absorb CO2. One example is Ecosphere that has been awarded the Cradle to Cradle Gold Certificate[iv].

Plastics

Plastics are frequently criticised for everything from their toxicity to their contributions to ocean pollution but unlike metals, plastics can be reused and recycled many times, without losing their chemical properties. Many are highly durable, long lasting and permanently installed, so they’re unlikely to become marine litter.

Whole-life carbon assessments for buildings

The construction industry has accepted a responsibility to reduce its carbon footprint and developments in materials, construction techniques, waste reduction, recycling and transport are continuing.

Against this backdrop it would make sense for whole-life carbon assessments for buildings to be set within building regulations and the planning system. This could provide a measure for progressive carbon targets for buildings, to match the pathway to net zero.

Insurance and the issue of betterment

From an insurance perspective, the question remains about the use of low carbon materials in repairs.

Insurers are not invested in the whole life cost of a building and need to be focused on cost to keep premiums affordable for all. In turn, loss adjusters such as Woodgate & Clark must ensure that there is no ‘betterment’ when it comes to repair specifications. Betterment is when a material is specified that is of a higher standard/performs better/costs more than the material being repaired or replaced. That is, unless policies were to allow for such alternatives to be considered.

Any longer-term view on material choices for repairs would need to be factored into the economics of the cost of insurance.  As stated earlier, that would require collaboration starting with a much wider debate with contributions from all corners of the insurance market and the consumers and businesses it serves.

There is wide acceptance that major weather events are linked to global warming due to CO2 emissions and that these events are increasing in both severity and frequency. It could therefore be said that insurers are directly affected by the level of CO2 emissions. Therefore, in a similar way to flood prevention measures being funded, perhaps the insurance sector might consider the additional cost of low carbon materials as a way of ‘futureproofing’ claims costs.

A step such as this would need much thought and discussion but it could certainly support the ABI Climate Change Roadmap[v] which focuses primarily on the sector’s role in supporting the delivery of the UK’s Net Zero strategy and meeting its carbon budgets.

Sources:

[i] https://www.constructionleadershipcouncil.co.uk/news/low-carbon-concrete-routemap-published/

[ii] https://researchportal.bath.ac.uk/en/publications/development-of-a-bio-based-plasterboard

[iii] Embodied carbon is the total carbon emissions of all building materials and products and the construction involved to put them together. It accounts for about 20% of the carbon emissions from the building sector.

[iv] https://c2ccertified.org/

[v] https://www.abi.org.uk/globalassets/files/publications/public/climate-change/abi-climate-roadmap---080622.pdf