Glue lamination process is a relatively new process is timber production. Glulam beams houses are now becoming increasingly popular among customers, often beating out classic options, such as log cabins, built from full, dried out logs. There are several factors leading this change in preference and one of them is surely the longevity of glulam timber frame houses. The process of glue lamination strengthens the wooden planks so much, the micro cracks in the wood are filled. This process prevents moisture from building up, which would eventually lead to decay in the whole construction.
Eurodita has been the bespoke log cabin company to fully adopt glue lamination as the core of our construction process. Because of that, in this post we have decided to introduce our readers with glue lamination in a bit more depth.
Types of adhesives on the market
To successfully make durable and sturdy glulam house frames, adhesives must be used in the wood bonding process. These are the most common adhesive types currently used on the market:
Phenol-based adhesives. Primarily used in the production of structural plywood and laminated veneer lumber (LVL), i.e. they are used to glue the veneer. Phenol-based adhesives consist of two or three components. They are cured at high temperatures, making it durable, but creating a dark adhesive seam in the process.
MUF adhesives. Otherwise known are two-component melamine-urea-formaldehyde adhesives. These are used in many wood products and are especially favoured for the production of finfer-jointed and glulam structures. MUF is also cured at high temperatures, but creates a completely colourless adhesive seam.
One-component PUR adhesives. Also known as polyurethane adhesives. Widely used adhesive for a variety of glue lamination purposes. PUR adhesives are used when producing finger joints, glulam products, cross laminated (CLT), face-bonding LVL sheets and more. PUR wood adhesives create a colourless seam when exposed to moisture at room temperature. They are prepared using polyol and isocyanate reaction – this reaction creates urethane bonds. This type of ingredients are also used on more commonplace items, including but not limited to upholstery foams, sporting shoes, furniture and more.
Emulsion polymer isocyanate adhesives. Made from dispersion adhesives and isocyanate cures. The drying can be done at room temperature, as that’s enough for the adhesive to harden. More commonly used outside of Europe, EPI adhesives are the preferred choice for constructions of small-dimensions, like glulam, finger jointing and laminated logs.
What makes glulam method special?
Glue lamination dramatically improves the integrity of all glulam elements. This includes not just beams, but columns, window frames, roof planks – any construction that used glulam becomes stronger and more durable.
As mentioned previously, glulam does not allow any moisture to build up in the micro cracks of the wood. It protects the timber from environmental conditions and stops fungus or microbes from festering in all the usually suspected places.
By using any of the adhesives, production process automatically demands planks or other constructs to be dried. The drying process itself usually takes place in a special drying rooms and further reduces moisture content to a minimum. And because of the adhesive, the moisture in the environment will not affect the glue-lines as much.
This is not to say that no additional care for glulam beam houses is needed. Eurodita and all our partners always recommend applying a varnish with UV block every 2-3 years to keep the timber safe from the elements. However, that is only going to strengthen the already superior construction and will prolong the longevity even further.
Glulam log homes are rising in popularity throughout Europe and beyond. Their strength doesn’t come at the expense of the environment, as all adhesives are safe deemed safe to use. With the added longevity, glulam timber houses with become eco-friendly alternative that can be passed down for many generations.