JJI-Joist Questions and Answers
Q. What is a JJI-Joist?
A. A JJI-Joist is a structurally engineered timber joist, combining high-grade softwood flanges with an engineered composite panel web. For more information please see our Product Range.
Q. How do I obtain JJI-Joists?
A. James Jones & Sons do not sell JJI-Joists direct. JJI-Joists are sold through a network of distributors, who will provide a design and quote based on a full set of architectural drawings. For a full list of distributors, please see How & Where to Buy.
Q. Can I use JJI-Joists in a ground floor construction?
A. JJI-Joists can be used in the ground floor construction of a residential dwelling. Various factors, however, must be taken into account. For more information on the design of ground floors using JJI-Joists, consult JJI-Joist Technical Bulletin 9 (Revision B) - Ground Floor Design and Restraint.
Q. Can JJI-Joists be used in the construction of roofs?
A. JJI-Joists can be used in the design of both flat and pitched roofs. JoistMaster V3 allows the user to design flat and pitched roofs.
Q. Can I cut or notch the flanges of JJI-Joists?
A. Under no circumstances must the flanges of joists be cut or notched. Should a flange become damaged, please consult JJI-Joist Technical Bulletin 43 for information regarding a remedial detail.
Q. Can I create holes in the web of JJI-Joists?
A. Holes for services can be created in the web of JJI-Joists. Please follow the Circular and Rectangular hole installation guides as printed in the JJI-Joist Technical Manual (Third Edition). Please see also JJI-Joist Technical Bulletin 7, entitled 'Holes in the Web of JJI-Joists'.
Q. Can I connect JJI-Joists to a steel beam?
A.Yes. Please see JJI-Joist Technical Bulletin 25 (Revision A) entitled 'JJI-Joist to Steel Beam Connection'.
Q. What Fire Protection do JJI-Joists offer?
A. JJI-Joists offer a variety of methods of achieving both 30 minute and 60 minute fire protection. Fire tests were carried out by Chiltern International Fire. The certificates can be downloaded here.
Q. I am a timber frame kit manufacturer and would like to buy direct and design my own JJI-Joists. What should I do?
A. Contact jji-joists@jamesjones.co.uk
Q. Is it possible to obtain separate 'E' and 'I' values for JJI-Joists?
A. This is not possible, due to a JJI-Joist being a composite material. Separate 'E' and 'I' values are only obtainable from a single material.
Q. Do JJI-Joists require preservative treatment?
A. This depends on the application. Normally JJI-Joists do not require preservative treatment. However, for more information on the preservative treatment of JJI-Joists please consult JJI-Joist Technical Bulletin 31 - JJI-Joist Treatment, or contact jji-joists@jamesjones.co.uk.
Q. My question is not listed. Where can I get more information?
A. Contact James Jones & Sons, Timber Systems Division, at our Forres address, or email jji-joists@jamesjones.co.uk for more information.
