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BiFold Doors - Lacuna

Lacuna Bifold Doors are designed and manufactured in Denmark and made to measure for each project. Flexibility is a key feature of the doors. You can customise them to match different designs, styles and architectural elements of exsisting doors and windows in any home. They have the slimmest profile available of any timber folding door with a 56 mm door frame that gives a frame to frame width of only 117 mm.

There are endless design possibilities and combinations with the width, height, frame types, in-door and outdoor colours, handles, glazing bars, horizontal mullions, etc.
Manufactured in acid-proof stainless steel, the hinges, handles and fittings guarantee a durable and timeless design. They are also available in powder coated black or white. Designed with double or triple sealing to meet the British PAS 24 standard and RC2N, and certified in accordance with C3 requirements.

We care about the environment. Insulation is therefore an essential factor to ensure a green and sustainable future. You can build a low-energy home, save on heating costs and reduce your CO2 impact when choosing Lacuna bifold doors.

View our full Contemporary Window and Door range here.
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TIMBER
DOOR OPTIONS
FINISH
GLASS OPTIONS
GLAZING BARS
hardware
IRONMONGERY
THRESHOLD
U-VALUES
TEST RESULTS
DURABILITY

Timber

Heat treated timber – TMT Composite®

TMT Composite® (Thermally Modified Timber) is the concept of Lacuna’s advanced heat-treatment, which Lacuna uses on FSC-certified, laminated German beech for painted bi-folding doors. No chemicals whatsoever, only heat, is used in the treatment. Through the TMT® process the timber obtains durability class 1, like teak, and a humidity of about 5.5%, making the modified timber very suitable for folding doors, as dimensional stability is extremely important for an airtight product that should not need adjustment due to changing weather conditions (moisture / draught).

At the same time TMT Composite® has a much better insulation as the treated wood does not absorb humidity as untreated wood would, resulting in bi-folding door that will last for many years. A sustainable process for sustainable construction.

European oak & FSC-certified sapele mahogany

We can also supply European oak and FSC certified sapele mahogany, without TMT Composite® treatment, oiled in a number of color tints. Pine and other soft woods are not used due to their lack of dimensional stability.

European oak

Main hardwood used for our windows and doors. Oak is the most popular hardwood, naturally beautiful, heavy, durable and strong.

Sapele mahogany

This is a reddish brown hardwood from Mahogany family imported from West Africa. Sapele is very hard, dense, stable and has beautiful natural grain, which is enhanced by applying a finish.

FSC-certified sapele mahogany

Bi-Fold door opening options

view from outside

view from outside

Lacuna outward-opening bi-folding doors are manufactured to individual measures from 1.5 m to 6 m width and max. 2.8 m height. The individual door leaves can be up to 100 cm wide (double glazed) and 90 cm ( triple glazed).

Lacuna bi-folding doors can be supplied in combinations with 3-9 leaves and with numerous options for the location of the master leaf.

There are numerous options and combinations when it comes to the number of leaves and the location of the master leaf. In order to be able to fold the door, an odd number of door leaves are required. This means that on a door with an odd number of leaves, all leaves fold to the same side. If the door has an even number of leaves, these will be divided so that an odd number of leaves open to each side.

Viewed from outside , opening options with varying number of leaves are shown below:

Finish

It is possible to choose among a number of surface treatments – either painted or oiled.

More than 90% of Lacuna’s products are painted TMT beech. Doors can painted in all colors, and also in transparent paint with UV filter on e.g. TMT Composite® pine. Outward-opening bi-folding doors are painted with the same technique as in the automotive industry, priming our products twice with sanding in between and applying two or three layers of top coat, depending on colour. The result is a super smooth surface (many believe it is painted aluminium) that is much more durable than through the traditional technique used in the window industry.

Oiled surfaces

For our oil-treated mahogany or oak products, cold-pressed linseed oil that seals the wood surface much better than water or turpentine-based oils is used.

Please note that oil-treated products should be re-treated at least three times in the first year after installation. This will saturate the wood and prevent drying cracks. Subsequently, depending on how much the parts are exposed to the weather, they should be re-treated twice a year. A transparent UV surface treatment for our Sapelli mahogany and oak products are also offered. The UV surface treatment is similar to painting and the elements do not need to be treated for the first many years.

Painted surfaces

In line with our principles, only environmentally friendly, water-based and proven durable paints are used. You can choose from a large number of RAL and NCS colors.

For items that are not particularly exposed, no paint treatment is required the first 25-35 years. The paint on thermally modified timber lasts longer without maintenance than on timber-alu products, as the TMT Composite adopts the characteristics of a composite or fibre-glass and do not extend nor retract when exposed to moisture or temperature.

Colour combinations

Modern buildings often have dark frames externally. Here often a lighter, possibly white colour is chosen internally. We can paint bi- folding doors in two or three colour combinations – also if desired, for example, oiled mahogany combined with a white colour.

Some options are:
1 - Combination of RAL 9005/9010
2 - Combination of RAL 7016/9010
3 - Mahogany, combined with 9010 and linseed oil
4 - Mahogany, oiled with cold-pressed linseed oil
5 - Mahogany, with cold-pressed black pigmented linseed oil
6 - Oak, oiled with cold-pressed black pigmented linseed oil
6 - Oak, oiled with cold-pressed linseed oil
We can also paint several types of texture as well as a colourless paint – like varnish.

GlasS

The glass is a major part of a folding door. It is therefore important that the choice of glass is correct. Besides double or triple glazing, Lacuna doors can be supplied with glass that meets different requirements and functions.

Please note that the more energy-efficient glass you choose the greater care you take of the environment. It is worthwhile investing in energy-efficient glass as the door and glass are built to last for many years

Glass Options

low-e glass

Low-E Glass is used as a standard in all our windows and doors.

It is specially treated with a microscopically thin, virtually invisible transparent coating on one surface. The coating reflects heat back into the building, thereby reducing the heat loss through the window.

toughened glass

Toughened glass is up to five times stronger than ordinary glass of the same thickness. Toughened glass is used where strength, thermal resistance, and safety are important.

laminated glass

Laminated glass is a type of safety glass that holds together when shattered. It provides even greater security levels than toughened glass, and it offers better levels of sound reduction and thermal insulation.

acoustic glass

Acoustic glass considerably reduces external noises, especially near busy areas such as motorways, main roads , railways and airports.

solar control glass

Solar Control Glass is a glass with a special coating designed to reduce the amount of heat entering a building. It reflects and absorbs heat as well as filtering light for reduced glare. Using a solar control glass can reduce the need for air-conditioning and blinds. There are many types of solar control glass offering different aesthetic options; tinted, reflective and neutral.

Bilfold doors can be also be supplied with other types of glass for example, self-cleaning glass, glass with integrated blinds etc.

Glazing bars

In line with our principles, only environmentally friendly, water-based and proven durable paints are used. You can choose from a large number of RAL and NCS colors.

For items that are not particularly exposed, no paint treatment is required the first 25-35 years. The paint on thermally modified timber lasts longer without maintenance than on timber-alu products, as the TMT Composite adopts the characteristics of a composite or fibre-glass and do not extend nor retract when exposed to moisture or temperature.

Helima Glazing Bars

As an alternative to the traditional glazing bars, we also offer Helima bars. There are bars built in between the glass panes. Thus, there are no bars on the outside or inside of the door. Helima is price-attractive and has a great advantage when it comes to cleaning. The bars are available in several widths: 18mm, 26mm and 45mm.

Panels

Lacuna also supplies panels that are flat or raised. The panels are not solid but laminated with a high-insulating material for the best possible insulation. Panels are supplied in the same colour as the door

Hardwear

All hardware is made from Danish marine-grade materials to prevent rusting in even harsh seafront locations.

Hinges

All hinges are stainless steel and are available in black, white or steel.

Top frame system

Lacuna folding doors also feature a revolutionary, patented top frame system with a guiding rail integrated into the top frame. This system provides ease of use, simple and cost efficient installation and an elegant finish.

The system is available in different versions, taking account of the load on the top frame. The system simplifies installation considerably. Lacuna doors can be installed in half the time of traditional installations, which increases their cost efficiency. When installed in existing houses, the patented top frame system often eliminates the need to add expensive iron or laminated wooden girders. Top frames are available with built-in carbon fibre reinforcement, which render the frame either fully or partly self-bearing.

Ironmongery

All ironmongery follows a strict principle of 18mm diameter and is manufactured in acid-proof stainless steel that guarantees a durable and timeless design.

Handles

Threshold

Stronger bottom frame

Continuing efforts to make the world’s best folding door, Lacuna constantly developing its products. For instance, the threshold has been upgraded to fibreglass so that it has become maintenance-free on the outside. Internally, the visible part of the bottom frame will still be wood. The reinforced fibreglass frame is available for both inward and outward folding doors.

Whole Lacuna Classic door U value

Ud
0.9 W/m2K

Test results

Air permeability
BS EN 12207
+/- 600 Pa
Class 4
Watertightness
EN 12208
+/- 600 Pa
Class E1200
Security
EN1627-30
PAS24

Durability

After almost 15 years in the market, Lacuna is known for its unique design and exceptional quality. Lacuna doors are made to last for 50 years or more.

Not only does the heat treatment of timber 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.

Extreme durability test

Beyond complying with international standard tests, Lacuna also performs its own extreme tests on moisture absorption, dimensional stability and insulation of the folding doors.
Lacuna pulled their TMT composite (heat treated beech) door frame out of salt water after being fully submerged for four months. After this full submersion, the paint had not cracked and it had only expanded by 0.4mm. This demonstrates the unique durability of Lacuna’s products.
Door frame was submerged in the sea for 4 months
Click here to view video
Sample was submerged in the sea for 1 year

Gutmann Weser Threshold

Optimal protection against water and cold
GUTMANN door threshold offers installation-friendly, high-performance and inexpensive solution for all front and balcony doors. It is gives optimal protection against water and cold and is rounded out with a matching accessory range.
High quality plastic thermal separation ensures the highest thermal insulation value
Reduces indoor condensation
Ensures an extremely high water tightness (600 Pascal)
The threshold holder produces a stable connection between the threshold and frame

Finish

We specialise in supplying and professionally installing high performance triple glazed windows and doors, offering both supply only and supply-installation services.
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