I-Joists
We are an authorised distributor of James Jones & Sons timber i-joists.
The JJI Joist is a structural, engineered timber i-joist, manufactured to UK preferred dimensions. Ideally suited for both residential and commercial applications, JJI Joists are available in a range of sizes (see our product comparison chart below for more information) and are FSC® and PAS 2050 accredited.
Product features and specifications
Superior strength
With a high strength to weight ratio, i-joists can be supplied in longer lengths than solid timber.
Quicker to install
I-joists weigh much less than solid timber joists, so are easier and faster to install.
High structural efficiency
I-joists don’t bow, warp or split, so your building will be stronger.
Durability and treatment
Standard product
JJI-Joists are untreated and when used in a Service Class 1 or 2 environment, the European Technical Assessment (ETA) certificate advises that the joists can be expected to have a service life in excess of 50 years.
Preservative treatment
JJI-Joists are also available with preservative treated timber flanges. This allows their use in Use Class 2 conditions in accordance with BS EN335-1, and Hazard Class 2 conditions in accordance with NHBC. This treatment does not affect the structural properties of the JJI-Joist. Please note a minimum order quantity will apply.
Compare joist depths and sizes
| Joist depth | A+ | B+ | C | D |
|---|---|---|---|---|
| 47mm | 63mm | 72mm | 97mm | |
| 195mm | ||||
| 220mm | ||||
| 235mm | ||||
| 245mm | ||||
| 300mm | ||||
| 350mm | ||||
| 400mm |
Darcy Attrill
Senior Staircase Estimator/Designer Stairs & I-Joists 01480 309900 [email protected] Request a quoteWe’ve worked with David Smith st Ives for a very long time. We need suppliers who can cope with our workload, and David Smith St Ives has plenty of capacity.
Kevin Dundas, Supply Chain Manager, Willmott Dixon
Relevant Case Studies
Request a quote
Tell us about your project and we'll get straight back to you to discuss your requirements.