Wood construction is the most affordable solution for low-carbon buildings

When calculating the emissions of construction materials, wood has a natural advantage, as it sequesters harmful carbon dioxide, keeping it away from the atmosphere. Foresters replace felled trees by planting saplings that grow into new carbon sinks. Increasing the share of wood construction is a natural way of bringing us closer to meeting our climate goals, without aby additional costs from outsourced emission compensation.

In the future, carbon footprint must be calculated for all buildings

The situation with the climate has urged us to set environmental objectives, due to which Finland will implement low-carbon building regulations in the mid-2020s. According to the Ministry of the Environment of Finland, the new law will oblige builders to assess the building’s carbon dioxide emissions by calculating its carbon footprint.

A low-carbon building is the result of extensive planning that takes account of the building’s life cycle. To help with that, the Ministry of the Environment of Finland is currently developing a uniform calculation policy for all builders. This policy will facilitate the work of Finnish builders by providing a way to consistently measure and assess the carbon emissions of construction. According to Matti Kuittinen, Senior Advisor at the Ministry of the Environment of Finland, the package is due to be completed by 2024.

To achieve a low-carbon result in construction, the size and purpose of the space to be constructed, as well as the foundation conditions, frame materials and energy sources must be planned and selected carefully. These are also what the calculation methods under preparation aim to support.

Matti Kuittinen, Senior Advisor at the Ministry of the Environment of Finland

Felled trees are replaced by planting new saplings

In wood construction, it is important to identify the wood’s origin. Responsible timber producers ensure the preservation of forests and cherish biodiversity. In the procurement of materials and services, we require responsible operation in accordance with UN Sustainable Development Goals. That’s why we only use wood from PEFC-certified raw material suppliers and aim to increase the use of FCS-certified wood.

The certificates guarantee that a new sapling will be planted for each felled tree and that efforts are taken to safeguard biodiversity. Choosing logs made of certified trees as the construction material is a natural way of creating a basis for the building’s small carbon footprint and ensuring that the material has been produced in a sustainable manner.

Log walls store carbon dioxide removed from the atmosphere

Solid wood is a super-material for low-carbon construction, as it sequesters carbon dioxide that is harmful to the environment and does not release it into the atmosphere. When a tree grows, it sequesters carbon, which also remains stored in the wooden walls of a building. Thus, a wooden building functions as a carbon store, and the saplings planted during its life cycle grow into new forests and form new carbon sinks.

According to the Ministry of the Environment of Finland, low-carbon construction should take account of the carbon footprint for the entire duration of the building’s life cycle. In addition to the construction phase, use and energy consumption, this also encompasses the manufacture and dismantling of building materials. A log building lasts from generation to generation. At the end the log building’s long life cycle, the materials can be recycled or processed further into biofuel.

Wooden buildings have a naturally smaller carbon footprint

When calculating carbon emissions, the cost-effectiveness of wood construction is based on its naturally smaller carbon footprint and positive carbon handprint. In terms of production, processing and transport, wood puts significantly less strain on the climate than conventional materials. According to Finnish Green Building Partners Oy, the carbon footprint of a solid-wood building is about 60 per cent of the carbon footprint of a conventional building during the production phase and about 75 per cent during its entire life cycle. What this means in practice is that there is no need to compensate the emissions of the material at additional cost.

The carbon footprint of a solid-wood building is about 60 per cent of the carbon footprint of a conventional building during the production phase and about 75 per cent during its entire life cycle.

Finnish Green Building Partners Oy

The importance of local production is underlined when the world situation keeps changing

It is clear to Kuittinen that the construction sector is undergoing a transformation now that the impact of the global situation increasingly urges us to choose the materials and plan the site to be built more carefully. In Kuittinen’s opinion, it would be a positive change if timber was used more for products with a long lifespan instead of products like tissues, which release carbon into the atmosphere quite quickly. “Of course, this change should be implemented in a way that prevents the number of trees felled from increasing,” says Kuittinen.

Unified carbon-emission calculation methods and indicators, such as those being developed in Finland, harmonise practices in the construction industry, as everyone has access to the same emission calculations and both municipalities and builders must strive to meet the same climate goals. Even in this uncertain world situation it is certain that the future of construction is low carbon. The special characteristics of wood help us meet the climate goals organically, without any outsourced compensation.