Nov 8, 2019 | News

Wave layered timber (WLT®) is a mass timber product developed for the building industry by Aalto Haitek Ltd., based in Ostrobothnia, Finland. Additive-free WLT® is strong, sustainable and highly versatile – a universal building component for every type of construction, including large buildings and bridges. WLT® is developed for industrial-scale production and can be manufactured using different types of wood around the world. Visually attractive and easy to build, the WLT® solution offers exciting possibilities for innovative design and is also a cost-efficient building method.

“Wave layered timber brings simplicity and flexibility to wood construction and is a competitive solution for the field of construction at large. No glue, additives or chemicals are used in its production or during the construction phase. WLT® does good for the environment as well as your business,” says Tiina Kapela, CEO, Aalto Haitek.

Unique characteristics of WLT®

The ingenious wave profile of WLT® combined with Aalto Haitek’s specially developed kiln drying technique creates a homogenous, crack-free and tight structure. The combination of its wave profile joining technique and all the wood grains going in the same direction provides unparalleled dimensional strength for wooden constructions, making it an ecological and economical alternative even for technically and aesthetically demanding structures. The component’s wave-shaped surface profile naturally optimises and regulates, with a spring-like effect, changes in tensions and dimensions caused by weather and climate-based humidity changes. 

WLT® makes practical and beautiful solutions possible even under demanding conditions such as emergency environments and locations regardless of shape, size or critical logistical restrictions and site requirements. The assembly of WLT® requires little or no training so that a bridge or a small house, for example, can be built without special equipment in hard-to-reach locations. 

WLT® components come in curved or straight shapes. The possibility to create round shapes, especially in wooden buildings, is a significant novelty that supports the creativity of architects and designers. 

Benefits of WLT® for builders 

Builders can significantly reduce construction costs and environmental impacts by using WLT® elements. The many benefits include:

1) Short lead, production and construction time 

2) Allows the use of a variety of wood species, including recycled wood 

3) Suited to most building methods – on-site, piece by piece construction to large modular assembly 

4) Zero waste and cost-efficient due to optimised production, structural strength and the light weight of WLT® 

5) Enables practical, ecological and beautiful solutions for demanding structural shapes and technical performance 

6) The massive, 100% additive-free timber structure is recyclable or degradable after disassembly 

WLT® elements are suitable for a wide range of large- and small-scale construction projects, including buildings, bridges and curved, tall, thick and thin structures. The massive, breathable structure provides an aesthetically pleasing, insulative, structural and fireproof solution. As a load bearing, fire resistant, insulative and light building component, WLT® is suitable for all the main building parts. The installation of WLT® elements is quick and simple as neither nails nor glue are required. 

Aalto Haitek has carried out mid-sized pilot projects since 2017 and is set to start the mass production of WLT® at its new factory in Finland during 2019. 

Different types of wood and chemical-free treatments can be used for WLT® 

The WLT® elements can be made from different species and kinds of wood. In Finland, the company is using Northern pine tree as its main source of raw material. 

WLT® can be combined with many treatments such as Accoya®, a patented acetylation process and brand name for modified wood. Acetylation makes the wood Class 1 durable, dimensionally stable and an ideal material for manufacturing high-performance timber products. Accoya® certified wood is reliable, non-toxic and fully circular wood, supported by a 50 year above ground and 25-year in- ground warranty. 

For more information, please contact:

Ms. Tiina Kapela, CEO, Aalto Haitek


Aalto Haitek Ltd. is a leading sustainable company that designs, develops and manufactures innovative, healthy, chemical- and glue-free massive timber products for wood building and the construction industry. Our patented technologies are rooted in Finnish know-how stretching back six generations. We are an active part of the growing bio and circular economy.

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