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4m Structural Composite Joist

In stock
WPC structural composite decking, 100 x 50mm Joist, Black, 4m length

Need help? Call Us on: 01837 659901

Monday to Friday 8am to 5pm, and Saturday 8am to 12.30pm.

4m Structural Composite Joist is available to buy in increments of 1

Start Your Project Properly with Our Structural Composite Joists

Making sure you begin your project in the right way is crucial, and our structural composite joists will do exactly that, enabling you to place your deck boards or cladding in the right way. Ideally placed onto a concrete base underneath, these structural composite decking joists will ensure that everything is correctly positioned and crucially give a strong foundation for your project.

Produced from recycled plastics and measuring 4000mm x 100mm x 50mm, the structural composite joists are available in charcoal colour only as they will lay the foundations for the rest of your composite deck boards to be fitted on top.

Joist Length: 4m

Joist Width: 100mm

Joist Thickness:50mm

Decking Joist Support You Can Trust

Used for elevated decked areas, you can also place structural composite joists directly onto grass if a solid concrete base isn’t an option. These are designed to ensure hard-wearing and long-lasting use for many years.

We recommend purchasing for every square metre of decking 1 structural composite joist and they should be spaced no more than 400m apart at a maximum so that your base is as strong and reliable as possible. For more on how to install correctly, consult our installation guides.

Please click on the variable options on our checkout page.

Cladco offer a Nationwide delivery service (UK Mainland) We offer a range of options, please see the table below.

Useful Links: Delivery Policy | Collection Policy


Delivery is estimated 10 working days (1-2 weeks).


Collection is from our Okehampton, Devon warehouse. Please note we need 5 working days noticed.

Sample Packs

Sample packs are sent via Royal Mail and delivered within 3-5 working days.


Sample Packs 3-5 Working Days FREE
Royal Mail
(Small Parcels)
3-5 Working Days £3.95
Parcelforce Standard
(Small Parcels)
3-5 Working Days £8.33
Parcelforce Express
(Small Parcels)
1 working days £10.00
Parcelforce Standard
(Large Parcels)
3-5 working days £22.00
Cladco Profile Delivery
(Local Delivery)
Estimated 10 working days £48.00
Cladco Profile Delivery
(Most postcodes)
Estimated 10 working days £72.00
Cladco Profile Delivery
(Scotland Delivery)
within 10 working days £360.00
WPC structural composite decking, 100 x 50mm Joist, Black, 4m length