Under the KP2 window console
12,13 € HT14,55 € TTC
Deck joists & substructure
A deck lasts only as long as its substructure. Our selection covers WPC composite joists (Hartika, 4DECK) for maintenance-free projects, and timber joists (Siberian larch, thermo-treated pine, Scandinavian spruce) for traditional substructures.
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products
45×70 Scandinavian spruce construction timber C14/V+
2,60 € HT3,12 € TTC
of which 0,02 € eco-contribution excl. VAT (0,02 € incl. VAT)
WPC composite decking board 2.3 × 14.6 cm brushed and grooved – Golden Teak, Silver Fir, Graphite Fir
56,38 € HT67,66 € TTC
Starter kit for composite decking boards 2.3 x 13.8 cm 4DECK Premium – 4 colours
17,00 € HT20,40 € TTC
Composite decking board 2,3 × 13,8 cm 4DECK Premium – 4 colours
74,48 € HT89,37 € TTC
HARTIKA grooved composite skirting 1 × 7.5 cm x 4 m
25,58 € HT30,69 € TTC
Composite decking joist HARTIKA 4,8 x 3,8 cm – 4 m
33,22 € HT39,86 € TTC
WPC composite decking joist 3 × 4 cm brown 4 m
13,99 € HT16,79 € TTC
HARTIKA composite decking joist 4.8 cm x 2 cm x 4 m
25,85 € HT31,02 € TTC
Thermo-treated pine square timber 4,2 × 4,2 cm, natural grade
4,87 € HT5,84 € TTC
Thermo-treated Scandinavian pine cladding 4,2 x 9,2 cm class NATUREL
7,61 € HT9,13 € TTC
Square Siberian larch joists 4,5 x 4,5 cm class AB
5,02 € HT6,02 € TTC
Thermo Sosna 42×140 decking board, NATUR class
77,82 € HT93,38 € TTC
of which 0,31 € eco-contribution excl. VAT (0,37 € incl. VAT)
Scandinavian pine 105×120, glued squares, class B
9,95 € HT11,94 € TTC
of which 0,09 € eco-contribution excl. VAT (0,11 € incl. VAT)
Scandinavian spruce 70×70, planed square, class AB
6,48 € HT7,78 € TTC
of which 0,04 € eco-contribution excl. VAT (0,05 € incl. VAT)
Scandinavian spruce 90×90, planed square, class AB
8,48 € HT10,17 € TTC
of which 0,06 € eco-contribution excl. VAT (0,07 € incl. VAT)
Scandinavian pine 105×180, glued squares, class B
14,93 € HT17,92 € TTC
of which 0,14 € eco-contribution excl. VAT (0,17 € incl. VAT)
40×60 LEGAR Exotique for terraces
8,33 € HT9,99 € TTC
of which 0,02 € eco-contribution excl. VAT (0,02 € incl. VAT)
Scandinavian pine 105×210, glued squares, class B
17,42 € HT20,90 € TTC
of which 0,16 € eco-contribution excl. VAT (0,19 € incl. VAT)
Planed squared timber Thermo Abachi (Ayous) 40×40, NATUR class
10,12 € HT12,14 € TTC
of which 0,01 € eco-contribution excl. VAT (0,01 € incl. VAT)
40×60 Exotic Glued LEGAR for terraces, class FJ
8,01 € HT9,61 € TTC
of which 0,02 € eco-contribution excl. VAT (0,02 € incl. VAT)
Scandinavian pine 94×94, glued squares, class A
10,04 € HT12,05 € TTC
of which 0,07 € eco-contribution excl. VAT (0,08 € incl. VAT)
Planed board Thermo Sosna 42×117 S4S, NATUR class
9,29 € HT11,15 € TTC
of which 0,04 € eco-contribution excl. VAT (0,05 € incl. VAT)
Scandinavian pine 94×94, glued squares, class B
7,79 € HT9,35 € TTC
of which 0,07 € eco-contribution excl. VAT (0,08 € incl. VAT)
Top sellers in this category
Under the KP2 window console
12,13 € HT14,55 € TTC
45×70 Scandinavian spruce construction timber C14/V+
2,60 € HT3,12 € TTC
WPC composite decking board 2.3 × 14.6 cm brushed and grooved – Golden Teak, Silver Fir, Graphite Fir
56,38 € HT67,66 € TTC
Composite decking board 2,3 × 13,8 cm 4DECK Premium – 4 colours
74,48 € HT89,37 € TTC
Starter kit for composite decking boards 2.3 x 13.8 cm 4DECK Premium – 4 colours
17,00 € HT20,40 € TTC
Our range by material
- Hartika WPC composite joists 4.8 × 2 cm and 4.8 × 3.8 cm in 4 m lengths — wood-polymer composite, unaffected by moisture, use class 4. Ideal for poolsides, concrete slabs and public buildings.
- 4DECK composite joist 3 × 4 cm in brown, 4 m lengths — the budget option.
- Siberian larch decking, smooth, 4.5 × 14.2 cm, grade AB — substructure or solid decking boards.
- Thermally modified Scandinavian pine and planed spruce 3.4 × 7 cm, grade AB — lightweight joist frames.
Sizing and installation
Joist spacing depends on the thickness of the boards: 40 to 50 cm for 2.6 cm boards, up to 60 cm for thicker sections. Raise the frame at least 4 cm on PVC pedestals or rubber shims to preserve the ventilated air gap — the one condition on which longevity depends.
Fixings: A2 stainless steel, or A4 on a seafront elevation. For composite joists, use the dedicated fixing clips (4DECK, Hartika) — never nails driven straight through.
Help & advice
Frequently asked questions
Everything you need to know before ordering. Another question? Contact us.
The WPC composite joist is unaffected by moisture, does not rot and needs no treatment — ideal beside a pool or on a concrete slab. The timber joist feels warmer, is breathable and more environmentally friendly, but calls for a durable species (larch, thermally modified) and careful ventilation.
Recommended spacing 40 to 50 cm. Reduce to 30 cm on cantilevered sections or in heavy-traffic areas.
Always use the dedicated fastening clips for the system (4DECK, Hartika, etc.). A screw driven straight through means a loss of watertightness — and of the warranty.