Buildings as
C sinks

With the new "Global Construction C-Sink" standard, OPENLY as C-Sink Manager can issue CO2 certificates for biogenic building materials used. Worldwide. From January 2025.

The
standard:

Together with Carbon Standard Internationaland the Ithaka Institute, OPENLY has been developing the "Global Construction C-Sink Standard" since 2022. Openly will launch this standard worldwide at MIPIM in Cannes (Road to Zero) in 2025. (Timber construction and hempcrete project registrations are now possible with completion date > 1.1.2022)

The standard is ICROA endorsed. It is based on the principle of additionality and focuses on > 60 years of structurally used, biogenic building materials such as construction timber, hemp, straw, bamboo and reed. The standard is a cooling service, i.e. represents a temporary C-sink and must be compensated for or renewed in 60+ years when the building is demolished. (see portfolio graphic below).

The calculation is net, i.e. minus emissions from farming, processing, transportation and installation. Certification takes place on the property (the building is the c-sink) in favor of the property owner. The owner can in turn use the certificates for insetting or sell the c-sink on the voluntary carbon market.

Also for renovations.


Construction Stored Carbon

Credit: Construction Stored Carbon

Use case:

The OPENLY VALLEY WIDNAU pilot project with 19 apartments has saved around 1000 tons of CO2 (avoided emissions, not certifiable) and stored an additional 750 tons of CO2 (stored carbon)

  • approx. 70 tons of biochar in concrete from CarstorCon

  • approx. 180 tons of hempcrete from Cancret.com (exterior insulation and non-load-bearing interior walls)

  • approx. 500 tons of construction timber


    The C-sink of Valley Widnau is therefore approx. 500 kg per m2 net floor area or approx. 330 kg gross floor area.

    Other certifiable C-sinks are possible with straw or grass insulation as well as structurally installed bamboo.


CDR - how it works

Plants as CO2 vacuum cleaners:
1kg of hemp binds around 1.7kg of CO2 during growth (3 months). Photosynthesis removes CO2 from the atmosphere.(Carbon Dioxide Removal)

CO2 balance based on Ökobaudat or KBOB (Switzerland):

Hempcrete: net negative emissions approx. -100kg/m3

Wood: net negative emission approx. -727kg/m3


Please note:

A) The aim of all must be to avoid CO2 emissions.
OPENLY engineered buildings achieve up to 4kg CO2 per gross floor area which means a reduction of up to -70%.

B) If certificates from carbon sinks are used for insetting or sold on the Voluntary Carbon Market, they can no longer be included in the carbon footprint of the building construction and the building can therefore no longer be designated "net zero".

C) If you are building without OPENLY advice, make sure that your suppliers of building materials have not already sold the C sinks on the market. If this is the case, these C-sinks can no longer be included in the calculation. (see e.g. Plantd, Neustark, Klark and other suppliers)

How?

The role of Openly

Lever of insetting:

As a C-sink manager, OPENLY supplies the CO2 certificates for your construction activities, which we immediately "decommission" for the neutralization of your core business. Groups such as NESTLE, ACCOR and BNP Paribas are already using such insettings today.
In particular, around 50,000 groups that have been subject to EU taxonomy reporting since 2024 can benefit from this.

The potential of buildings as C sinks

The annual C-sink potential is around 5 gigatons of CO2.

We expect over 100,000 tons of certified sink output as early as 2025/26. In 2027, we want to become a megacorn and certify 1 million C sinks from biogenic construction activities annually and make them available to the market.

Note:

  • The building is the C-Sink
    -> The sink service belongs to the property owner who ordered and paid for the biogenic building materials

  • Our "Global Construction C-Sink" standard provides a temporary sink while the building is standing.

  • These C sinks are recognized by the EU

In the future, we will switch to a portfolio approach