Decking Joists

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Special Offer

Special Offer

C24 Timber Decking Joists UC4 Treated Kiln Dried Regularised Redwood 47 x 100 x 3600mm (4x2)

WAS: each

WAS £18.73

£12.24 each (Inc VAT)

WAS: each

WAS £15.61

£10.20 each (Ex VAT)

Crafted for durability and strength, our C24 Timber Joists UC4 Treated Redwood 47 x 100mm x 3.6m are the ideal choice for your outdoor decking projects. These joists are UC4 treated, ensuring they are well-suited for ground and water contact, making...

WAS: each

WAS £18.73

£12.24 each (Inc VAT)

WAS: each

WAS £15.61

£10.20 each (Ex VAT)
Special Offer

Special Offer

C24 Timber Joists UC4 Treated Redwood 47 x 150 x 3600mm (6x2)

WAS: each

WAS £28.10

£18.36 each (Inc VAT)

WAS: each

WAS £23.42

£15.30 each (Ex VAT)

Discover the exceptional quality of our C24 Timber Joists, expertly crafted to support your decking projects with strength and reliability. Made from premium UC4 treated Redwood, these joists are ideal for outdoor use and can withstand direct ground...

WAS: each

WAS £28.10

£18.36 each (Inc VAT)

WAS: each

WAS £23.42

£15.30 each (Ex VAT)
Special Offer

Special Offer

C24 Timber Joists UC4 Treated Redwood 47 x 100 x 4800mm (4x2)

WAS: each

WAS £21.07

£16.32 each (Inc VAT)

WAS: each

WAS £17.56

£13.60 each (Ex VAT)

Elevate your outdoor projects with C24 Treated Timber Decking Joists, meticulously crafted from premium Redwood and UC4 treated for exceptional ground contact durability. These joists are engineered from dense Scandinavian softwood, offering...

WAS: each

WAS £21.07

£16.32 each (Inc VAT)

WAS: each

WAS £17.56

£13.60 each (Ex VAT)
Special Offer

Special Offer

C24 Timber Joists UC4 Treated Redwood 47 x 150 x 4800mm (6x2)

WAS: each

WAS £37.46

£24.49 each (Inc VAT)

WAS: each

WAS £31.22

£20.41 each (Ex VAT)

Add the long lasting UC4 C24 Timber Joists to your garden, expertly designed for durability and strength. Ideal for constructing robust decking structures, these joists are UC4 treated, ensuring they withstand direct ground contact and resist moisture,...

WAS: each

WAS £37.46

£24.49 each (Inc VAT)

WAS: each

WAS £31.22

£20.41 each (Ex VAT)

When choosing the right decking joists for your project, the size you need will depend on the overall dimensions of your deck. We offer a variety of decking and joists in different lengths, all available for delivery from any of our branches. For timber decking, a good rule of thumb for decking joist spacing is 450mm centres (or 400mm if using a chevron pattern). For composite decking joists, spacing should be 400mm centres, or 300mm when opting for a chevron pattern.

Additionally, consider using deck joist tape to protect the joists from moisture, and joist hangers for decking to ensure a secure and durable installation.

Frequently Asked Questions

What size deck joists?

The deck joist size required depends on your project design. Our most popular sizes are 47x100mm, 47x125mm, and 47x150mm. These are available from every Howarth branch in lengths of 3m, 3.6m, 4.2m, and 4.78m. We also have availability of 5.4m and 6m at select branches

What size screws for decking joists?

Camo deck screws are perfect for fastening deck boards to joists. For the framing, structural wood screws will do a great job.

How far apart should deck joists be?

When designing how far apart your deck joists should be, a good timber decking spacing is 450mm centres (or 400mm centres is using a chevron pattern), and 400mm centres for composite decking (or 300mm centres if using a chevron pattern).

How many decking joists do I need?

The number of decking joists needed is dependant upon the size of the decking project. It can be calculated based on spacing of 450mm centres for timber decking (400mm centres for chevron pattern) and 400mm centres for composite decking (300mm centres for chevron pattern).

What wood to use for deck joists?

C16 or C24 timber is ideal for decking joists. It is structural graded and when well put together will keep the decking strong and stable.

How thick should decking joists be?

Decking joists are most commonly 47mm in size.

Should I stain deck joists?

We always recommend treating timber and maintaining it over time, this includes decking joists. This will increase the longevity of the decking structure. Don’t forget to protect the ends!