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Tropical hardwood Joists

Exotic wood joists

Durable (class 1-2)
Easy to install
FSC certified
All you need to know
  • Very durable
  • Quick to install
  • 16% dried wood
  • Durability class 1
  • Different sizes available


Red Balau

FelixWood profiles

Solid Wood: 42x65, 45x90 mm

Glulam wood : 40x60, 42x68, 45x70, 45x 90mm

Solid or glulam joists

The structure of a wooden deck should be as durable as possible. Exotic wood joists in Bangkirai, Kapur and Red Balau are all in durability class 1 to ensure the best possible durability of the deck and thus, protection from insect attacks and lignivorous fungi.

It is important to use joists that are as straight as possible and without deformation to ensure quick and easy installation.

Because solid wood is not always perfectly straight, we offer you naturally durable glulam butt ended joists.

As a precautionary measure, we recommend the use of a Bitudeck type bituminous strip to protect the adhesive joints from any moisture.

Advantages of glulam timber joists

Much more stable than solid wood - Very little deformation. Any side can be used

Saving of raw materials with better management of production scrap waste. Available in large fixed standard lengths (up to 3.9m), making it easy to install.

Disadvantages of glulam timber joists

The span between support points is reduced compared to solid wood (50 cm maximum).

Danger of cracking of the adhesive joint if a hole is drilled between two lamellas at an adhesive point. (To avoid this, use Bitudeck bitumen tape.) Do not use as a handrail or furniture part.

Always ensure good ventilation and drainage under the terrace. Also ensure protection against weather and UV radiation during storage.

However, these disadvantages do not outweigh the advantages of glulam timber joists over solid wood when installing a wooden deck.

Installation and storage advice

Maximum span of 50 cm between 2 supports. Mechanical overload can lead to cracking of the adhesive joints.

Always store the joists in a dry and weatherproof place.

Never place the joists directly on the ground. Always ensure good drainage of rainwater under the joists (e.g. with rubber spacers or adjustable pedestals).

Ventilation is very important. Air circulation through deck boards spacings is not sufficient. At least 2 cm of space must be maintained around the contour of the terrace for air circulation.  If this is not possible, install ventilation grilles.

Use Bitudeck sealing tape to protect the joist against water infiltration into the cracks in the wood and glue joints.

Available sections of glulam joists :

40 x 60 mm max. centre distance 50 cm / 42 x 68 mm max. centre distance 50 cm / 45 x 70 mm max. centre distance 50 cm / 45 x 65 mm max. centre distance 50 cm

Simple joist installation

Plan a centre-to-centre distance of between 40 and 50cm between joists. This distance is specified for each of our profiles in the attached table.

The joists must be laid with a slope of 2% in the longitudinal direction of the boards to allow rainwater to run off. This 2% slope must be strictly observed!

Water, too, must be able to flow under the structure. The joists must be supported on rubber blocks or pedestals.

Protect your joists and increase their lifespan: Use the Bitudeck bitumen strip to cover the joists and prevent water infiltration at the fixing points.

Double joisted and cross-joisted

Double joisting allows for water to flow between the ends of the boards. The distance between the ends of the boards must be between 4 and 6 mm and the distance between the end of the board and the joist must be between 20 and 30 mm.

Cross joisting

For a faster and longer lasting installation, we recommend laying on a cross-joist.

A bed of joists is fixed perpendicularly on a first level of rafters. The flatness of the terrace is easier and quicker to adjust, and ventilation is improved.

In the case of loose and poorly stabilised soil, we recommend the use of galvanised steel foundation screws to ensure effective and durable anchoring of your terrace.

The boards are screwed to the wooden joists

Spacing between the decking boards should be kept between 5 and 7mm (taking into account a wood moisture content of 14-16% at delivery). Use board spacers during installation.

Humidity of the boards from 12 to 17% from 18 to 22% > 23% to H > PSF
Thickness of the spacer shim           7 or 6 mm                            5 ou 4 mm                          3 ou 2 mm                          


To avoid water being trapped between the boards and the joists, we recommend the use of a ventilation wedge of the Airspacer type. Air circulation under the boards prevents any moisture settling.

Ensure good ventilation of the boards

Never completely close the skirts of the terrace to "let the air circulate". Leave a ventilation space of 2 cm between floor and skirting. The minimum space between the decking boards and the ground should be 4 cm to 10 cm for damp floors.


Technical documents

Deck Boards
Fasteners and tools
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