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Carrying a lot of weight - Multifaceted adhesives for load-bearing glulam

House of Technologie Jowat Glulam

The manufacture of load-bearing glulam is governed by strict regulations. Apart from having to be certified, the special adhesives used for bonding the wood also must fulfil the different requirements of all applications in load-bearing timber construction. A new product family in the Jowapur® series supplied by Jowat, the adhesives manufacturer from Detmold, provides a comprehensive portfolio of certified one-component prepolymer PUR adhesives, with different formulations for a wide variety of processes in the manufacture of load-bearing glulam.

Load-bearing glulam plays a growing role in the construction industry and the use of load-bearing glulam in new buildings has been increasing for years. Intense development efforts are underway to make sure the technology meets the growing quality requirements. Jowat, the adhesives specialist from Detmold, supports that development with its know-how acquired over many years, an optimum service, and with a brand new, fully certified set of adhesives.

The right answer for every need
The new adhesives are certified according to EN 15425:2017 and their composition, characteristics, and processing parameters are specifically tailored to the requirements of load-bearing glulam applications. They can be used for fingerjointing as well as for laminating, offer the choice of assembly times between 10 and 60 minutes, and for the first time facilitate an assembly-pressing time ratio of 1:1. Industrial users can therefore optimise their processes by choosing the product best-suited for their needs. A simple change of adhesive, for instance, can help increase their production capacity or alternatively improve process reliability without the need for major investments.

Clear benefits: PUR
Compared with other adhesive systems for the manufacture of load-bearing timber components, polyurethane adhesives provide several advantages in the manufacturing process and quality of the end product because of their characteristics. They are completely free of formaldehyde and require significantly lower application amounts due to a solids content of 100 %. Depending on the formulation, the prepolymers cure at room temperature already within a very short time and are colourless, with no discernible glue line. The adhesives from the Jowapur® series are processed as a one-component system, making mixing, pot life, and adhesive remnants from production obsolete. The limited foaming can help prevent the lams from sticking together when they are temporarily stacked on top of each other or placed next to each other, and therefore considerably reduces the cleaning effort.
The Jowapur® prepolymers are reinforced with fibres that increase the bond strength and prevent the assemblies from sliding apart in the manufacturing process and while the adhesive is curing. Due to optimised flow properties, these adhesives are ideal for contactless application systems in fingerjointing units.

Impressive constructions
From Jowat’s point of view, glulam will continue to become more and more significant in future – a development that should be accelerated with optimised adhesives. “Building with engineered timber brings only advantages,” says Ralph Kirst, responsible for load-bearing glulam business development at Jowat SE. “Furthermore, adhesive bonding facilitates the manufacture of timber constructions in less time and at lower costs. Entire buildings can be prefabricated in mass production and assembled on site.” In light of these advantages, chances are more and more property developers will start using engineered timber. Not only does it make sense from an economic and ecological point of view – wood stores CO2 and helps fight against climate change. Glulam also allows for virtually limitless possibilities in modern architecture, as is demonstrated by the eye-catching design of Jowat’s “House of Technology” in Detmold or the BUGA Wood Pavilion in Heilbronn.