PUUSTER – Development of methods for the valorisation of underutilised wood and wood material in construction
PUUSTER is a five-year interdisciplinary research project led by Tallinn University of Technology, the University of Tartu, and the Estonian Academy of Arts. The name combines the Estonian word puu (tree) with the idea of boosting — reflecting our mission to give new life and value to wood resources that are often overlooked.
Project executors: EKA PAKK, Taltech, University of Tartu
Involved: dr Sille Pihlak, dr Siim Tuksam, dr Renee Puusepp, Kaiko Kivi, Anna Tommingas
Period: 1.01.2024-31.12.2028
Funding: co-funded by the European Union and the Estonian Research Council (TemTA80)

Together with leading industry partners, we explore how bark beetle–damaged timber, industrial by-products, and forest residues can be transformed into sustainable construction materials. Our goal is to accelerate the transition towards circular, resource-efficient building practices and strengthen the competitiveness of timber as a trusted construction material.


Of the merchantable timber originating from Estonia’s forest land, 57% goes to fuelwood or pulpwood (Wood Balance 2021), and alternatives to this are being actively developed. We must move toward higher value-added uses of wood in order to lock in the carbon it contains over the long term. In recent years, demand for wood as a construction material has surged, because the production of construction materials accounts for a little more than 10% of total carbon emissions, and wood helps reduce the construction sector’s carbon footprint. Nevertheless, the resource available from forests is not limitless, and we must develop ways to ensure that every tree felled (or fallen) finds a long-term use.

We see great potential to deploy, alongside the coniferous species already used in construction, wood species that have so far been underutilised due to the lack of suitable technologies. We need to add more value to low-grade wood damaged by storms or bark beetles. According to RMK, roughly 330,000 m³, or 16%, of the annual conifer harvest is affected by bark beetle and is not used as a structural material. Nor should we overlook the reuse of wood in line with circular-economy principles—both demolition wood and industrial residues. For example, depending on the project, CLT offcuts can account for 5–20% of the material consumed, and today these are directed primarily to energy production.

Research topics:

  • Application of underused wood species (e.g., hardwoods) in construction

  • Integration of low-grade wood (e.g., storm- and bark-beetle-damaged timber) into new wood products

  • Reuse of wood (e.g., demolition timber, industrial residues)

  • Circular use of industrial residues and demolition waste

  • Mechanical valorisation of low-grade and underused wood

  • Digital solutions for sustainable monitoring, design, manufacturing, and construction

The research teams include TalTech’s Structural Engineering Research Group, TalTech’s Wood Technology Laboratory, the Estonian Academy of Arts’ Timber Architecture Research Center (PAKK), and the University of Tartu’s Institute of Physics. Industry partners are Peetri Puit OÜ, Thermory AS, the Estonian Forest and Wood Industries Association, Combimill Sakala OÜ, and Estonian Plywood AS. 
Opening seminar @Taltech with industry partners September 2024
The research benefits Estonia by upgrading underused coniferous and hardwood into engineered-wood products. Significant untapped value lies in low-cost hardwood logs—especially aspen (€61.60/m³) and black alder (€68.65/m³); state forests produce ~45,000 m³ and ~23,000 m³ respectively but lack stable demand (source: 2023 3kv puiduturu ülevaade, Erametsaliit). Bark-beetle-damaged conifer logs are mostly burned, and much hardwood is exported as roundwood or turned into fuel; demolition wood and industrial residues are likewise underused. A science-based programme will mobilise these resources: companies are willing but need a research foundation to create products, expand portfolios, and gain advantage by turning reclaimed wood and residues into low-impact standard materials. Expected results: divert damaged logs from energy to engineered products for construction; increase use of local material, reduce import dependence, and grow jobs.
Research partners

Industry partners