Posi Joist Metal Webbed Floor Joists.

Easy access for the installation and maintenance of the services in a floor zone is the clear advantage of the Posi-Joist flooring system. 

With the move towards the building of more sustainable homes, an increasing number of mechanical ventilation and heat recovery (MVHR) systems are being installed in the UK and Ireland, driving more and more architects and specifiers to look for a versatile open web flooring solution.

Why choose Posi-joist’s over other joist and rafter systems.

The system combines the lightness of timber with the strength of the Posi-Strut™ steel web, enabling you to span far greater distances than would be possible with alternative timber products, allowing a variety of internal room layouts within an external shell. This gives you unequalled design freedom across a wide range of applications for both floor and roof in domestic, industrial, and commercial applications.


- No more putting holes thought your floor joists Posi-Joists making installation of services a breeze.


- All Posi-joist floors or roofs are manufactured to order reducing the need for site alterations and waste.


- Quick to install and much lighter than traditional floor joist and other engineered joists.


- Joist come with a full layout and profiles. Out calculations are produced in accordance with EC5 regulations.


Whilst an initial linear metre cost comparison with solid joist alternatives may suggest otherwise, Posi-Joist’s ability to span greater distances than its timber competitors, coupled with its open web design gives the contractor several important cost saving advantages.


The span capabilities mean that Posi-Joist can often allow for increased joist centres when compared to alternative systems, reducing material content.


The installation of services and utilities is far simpler and quicker with Posi-Joists, reducing both labour costs and build-up time on site.

Joists are manufactured in a controlled offsite environment ensuring a quality product and are delivered ‘made to measure’ allowing for speedy erection. What’s more, Posi-Joists will often eliminate the need for load-bearing intermediate walls, all of which can dramatically cut overall building costs.


Design flexibility is inherent in the concept of the Posi-Joist. The depth, length and width can all be adjusted to produce an enormous number of different specifications, each with clearly defined performance criteria. In addition, end details of the Posi-Joist can be altered to give a variety of support conditions.


Posi-Joists can incorporate a Trimmable End, incorporating a solid timber block which can be engineered to give up to 130mm allowance at each end for trimming on site.


Why not try Posi-Joists on your next build. 


Please feel free to get in touch with our estimation team to find out if our metal webbed joists are a good fit for your next build just follow the link below to our enquiry's pages or alternatively please feel free to email us at enquiries@triadtimber.co.uk or give us a call on 01903765167 where one of our members of staff will be on hand to assist.

Contact us.

Additional information on Posi Joists can be found by following the link below to our technical information page





MiTek Span-calculator can give you an idea of what depth of joist you might require to achieve your required clear span.

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