Lacuna bi-fold doors, designed and manufactured by the Danish company Lacuna A/S, are now being promoted on the British isles by their new distributor Lacuna UK and Ireland, and their associated partners/showrooms.

Compared with other established bi-fold door brands, the Lacuna doors are relatively new on the UK/Irish market having only been available here in the last few years.

One of the main features of the Lacuna bi-fold doors is the use of heat treated wood. It is this special property that sets the Danish doors apart from the other brands on the market. The heat treating process consist of concealing the wood in large 200 degree hot ovens for 24 hours, whereby the structure of the wood changes permanently and gains a number of advantages, which ordinary soft or hard woods do not have.

The Vikings and Lacuna

Heat treatment is not a new invention – whenever a Viking ship has been found at the bottom of Roskilde Fjord in Denmark, it has primarily been the keel that has been intact. To bend the bow and stern keel, the Vikings heat-treated the wood in hot embers, using water cooling to ensure that it did not catch fire. Once the wood was warm and smooth, the keel was bent into the desired shape. In this way, the sugars (Lactose and Glucose etc.), which the decomposition bacteria would otherwise live off, were burnt away and the wood achieved the unintended effect of a lifespan of many centuries.


Natural durability, dimensional stability and low maintenance requirements

Not only does the heat treatment increase the natural durability (and becomes equal to teak -Class 1) it also makes the timber very stable, and accordingly it is unable to absorb moisture and expand in humid weather. This is obviously an essential attribute for folding doors, where many panels in succession need to keep their dimensional stability in order to function properly all year around. It furthermore means that the paintwork does not crack and maintenance therefore is at a minimum.

Insulation properties

Another advantageous effect of the heat treatment is the air-filled structure that the timber adopts. It basically gains the characteristics of fibreglass and consists of many small air pockets neatly packed together. It is these that give the wood the excellent insulation properties and thereby the low u-value.

Summary

Lacuna bi-fold doors: The materials have been tested at the German testing centre IFT- Rosenheim and subsequently the doors have been certified by the approved testing centre at Danish Technological Institute. They have total u-values typically down to 0.9 W/m², air permeability has been tested to EN 12207 - Class 4 at +/-600 Pa, water tightness to EN 12208 Class E1200 and security to EN1627-30.

www.lacuna-bifold.co.uk