Our JJI-Joist system combines the JJI-Joist products with custom sized glued laminated timber (glulam) and system specific metalwork to create a highly flexible offering, ideal for framing structural floors, roofs and walls.

Like all James Jones' products, the JJI-Joist production process has been independently audited to PAS 2050 standard meaning we are able to provide accurate carbon negative numbers for those customers looking to measure the carbon footprint of their project.

JJI-Joists

JJI-Joists are the most widely specified engineered wood product in the UK and are used in residential and commercial construction as load-bearing and non load-bearing members for floors, walls and roofs.

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Glulam

James Jones & Sons' Timber Systems Division is a leading supplier of high specification glued laminated timber (Glulam) specifically sized to suit the JJI-Joist product range, in partnership with Austria-based Binderholz.

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LVL

​In partnership with Stora Enso, we supply the UK construction sector with laminated veneer lumber (LVL) suitable for a wide range of structural applications and in sizes to complement our JJI-Joist range.

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Interactive Span Table

If you are considering using JJI-Joists in your construction project, use our Interactive Span Table to quickly identify the size and specification that you will require.

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Distributor Map

JJI-Joists and our other engineered timber products are available through our network of distributors. Please enter your postcode in the space below to find your nearest distributor.

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Design Tools & Support

As our Timber Systems Division has grown we have built an expert support team and a range of design software to make using the JJI-Joist system as easy and efficient as possible.

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Carbon Data

James Jones was the first UK timber company to undertake PAS 2050:2011 carbon reporting so we can measure all the carbon locked up in our timber products.

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CPD Courses

Our Timber Systems Division team offer face-to-face seminars on Engineered Wood Products covering all aspects of designing and working with JJI-Joists.

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JJI-Joist Distributors

Our engineered wood products are sold by a dedicated UK network of more than 20 distributors.

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Company Projects

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Downloads and Certifications

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News related to
Engineered Timber

New JJI-Joist Technical Manual published by James Jones

James Jones & Sons Ltd's Timber Systems Division, the leading supplier of JJI-Joists, Glulam and LVL to the UK’s construction sector, has published the fifth edition of its UK Technical Manual, which has been fully updated to Eurocode 5.

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JJI-Joist division forms stairwell protection system partnership

James Jones & Sons’ Timber Systems Division has entered into a partnership with specialist building materials manufacturer Ockwells, which will see it recommending Ockwells’ Stairwell Hatch System to all JJI-Joist customers.

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New JJI-Joist line to become the world’s most modern line in 2019

Structural work is now complete and installation is underway on what will become the most advanced I-Joist manufacturing facility in the world once it is compmissioned at James Jones & Sons Ltd's site in Forres later this year.

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Moray students get hands-on to discover what timber sector could offer

Around 80 school students visited Dipple Farm, close to James Jones & Sons Ltd’s sawmill in Mosstodloch, last week to find out what career opportunities exist on their doorstep in land-based industry across Moray.

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Over £8 Million to be invested to build world's best I-Joist line at Forres

James Jones has today announced a major new £8.5 Million investment at its JJI-Joist assembly line in Forres that will create a world-leading I-Joist production line in Forres, Scotland and more than double capacity.

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James Jones supplies larch for a fascinating Lake District project

James Jones and Sons has helped architectural students from Central Saint Martins with a project to build an information kiosk and community bread oven in the grounds of the Ruskin Museum in Coniston.

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James Jones launches innovative palletguard system UPALL®

James Jones & Sons' Pallets division has revealed a new venture it says will dramatically improve the quality, length of life and environmental benefits of wooden pallets, and significantly reduce their whole life cost.

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James Jones supplies timber for hospital grounds' viewing platform

James Jones and Sons Ltd has supplied the timber for the viewing platform in the grounds of the Forth Valley Royal Hospital, near Larbert.

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Negative Carbon is a Real Positive for Designers says James Jones

The UK government acknowledges that the construction industry has an important role to play in the reduction of Greenhouse Gases (GHGs) to mitigate Climate Change as it could influence 47% of all GHG emissions in the UK.

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James Jones Timber Systems Division expands Forres manufacturing site

The Timber Systems Division of James Jones and Sons Ltd this week confirmed the purchase, from the local council, of additional land next to its existing JJI-Joist manufacturing plant in Forres,

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New Sizes Plus Updated Software From James Jones – Joist The Ticket!

​Suitable for roof, wall and floor applications, the new I-Joists provide a full portfolio of joist widths; 47mm (A+), 63mm (B+), 72mm (C) & 97mm (D), for I-Joist depths ranging from 350mm to 450mm.

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JJI-Joists’ Carbon Accounting Adds Up For CfSH

​Manufactured in the UK, FSC certified and EUTR compliant, JJIs are therefore making a real contribution to sustainable construction and to achieving required levels of Code for Sustainable Homes.

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James Jones and Sons Ltd joins Get Britain Building campaign.

James Jones & Sons Ltd, leading processors of British timber and engineered timber products, is now supporting the Get Britain Building campaign.

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James Jones Announces Development Of BIM-Supporting Software

The summer 2013 release of FloorMaster will have an option enabling it to export to IFC format files, allowing a 3D BIM model of the fully engineered James Jones structure to be picked up by anyone using Revit,

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James Jones Timber Systems supports first net zero carbon timber structure in the UK

The project, located at Dundee’s Botanic Gardens, is creating one of the first full scale, fully autonomous, net zero carbon timber structures in the UK.

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Winners of Housebuilder ‘Best Product’ and ‘Best Regeneration’ Awards used JJI-Joists

The joint winner in the ‘Best Product' Category, the RoofSpace I-RoofTM, incorporates JJI-Joists and BJ Beam glulam in the roof scheme; and the winner of the ‘Best Regeneration Project' Category,

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James Jones Timber Systems Announce Latest I-Joist Products

The preservative treated JJI-Joist is the only UK manufactured I-Joist which is low pressure treated for use in projects that require protection to UC1 and UC2, in compliance with BS EN 331-5.

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James Jones & Sons Ltd joins Get Britain Building campaign

The company has added the campaign logo to its emails, website and new literature and is encouraging customers, our customers' customers' and our partners in the timber and allied trades to follow suit and join the campaign.

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James Jones Sponsor Seminar Theatre 3 at Timber Expo, Coventry, UK

The James Jones technical sales team will be at Timber Expo to welcome visitors throughout the two days and provide information on the range of James Jones products.

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James Jones TSD Design EC5 Compliant Roof

The approach from Boards Cottingham was to fabricate the roof structure in six sections and to supply the structural and other timbers to site with every joist cut and numbered, to ease the construction process.

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Ecobuild Delivers More Continental Europe opportunities for James Jones Timber Systems

James Jones & Sons Ltd, Timber Systems Division are already established exporters to Continental Europe, in partnership with leading Belgian timber merchants VC Wood,

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Walking With The Wounded

On Saturday April 16 2011, the Walking With The Wounded North Pole Expedition Team skied into the record books, as they became the first team of unsupported war-wounded amputees to reach the Geographical North Pole.

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James Jones’ Ecobuild stand S1775 is a unique showcase for the JJI-Intelliroof™ System

The company’s stand will be built using the IntelliRoof which will incorporate a solar panel and a cabrio Velux window.

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Our reputation for quality and service speaks for itself

Certification &
Downloads

Find all the relevant compliance and technical downloads relating to sawn timber, JJI-Joists and pallets and packaging.

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Tree to
Timber

Find out about the process all our high quality products go through before reaching our customers.

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Interactive
Span Table

Enter your span and load conditions and receive a list of joists suitable for your application:

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