a 3D render of a home with posi-joists installed

What is a Posi-Joist?

Posi-Joists, also known as metal web joists or engineered joists, are a structural system combining timber and steel webbing, designed for use in both floor joist and roof applications. Each joist consists of a top and bottom chord, end columns, and steel webs positioned in between. Unlike traditional solid joists, they're designed in specialist software and made in a controlled environment, allowing us to add or subtract loads, try different variants, or position them in various ways before the manufacturing process begins.

Why Choose Posi-Joists?

Posi-Joists excel in a number of factors, but the most prominent is their ability to span vast distances, and the ease of routing services through their open web design.

Long Spanning

Posi-Joists can span significantly greater distances than traditional solid timber joists while also offering a lighter overall weight. This makes them particularly well-suited for modern construction methods, where open-plan layouts are increasingly popular. The extended span capabilities of Posi-Joists reduce or eliminate the need for internal loadbearing walls or intermediate supports, creating more flexible and adaptable floor layouts.

Easy Service Routing

Thanks to their open web design, Posi-Joists also provide a convenient service void for running plumbing, electrics, and ventilation systems without the need for costly drilling or notching — reducing installation time and minimising potential structural compromise. Whether you're building a new home or undertaking a renovation, Posi-Joists offer a high-performance, cost-effective solution for almost every project.

  • Lightweight 🏋️‍♂️

    Posi-Joists use less material to achieve the same strength as solid timber, making them significantly lighter. This is a major advantage if you're working on a site that can't accommodate a crane or if you want to avoid the associated costs.

  • Easy to install 🔨

    Posi-Joists are manufactured to the size of your building and can be simply dropped into place. If your building isn't perfectly straight (which, let's be honest, most old buildings aren't), Posi-Joists can be supplied with trimmable ends.

  • High quality ✏️

    Posi-Joists are designed in specialist software and produced under factory-controlled conditions, ensuring an unmatched level of quality every time.

  • No shrinkage 🏡

    Posi-Joists don't suffer from shrinkage or distortion, a typical cause for a squeaky floor. 

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FAQs

What are the benefits of using Posi-Joists?

They offer increased strength, reduced weight and greater spanning capabilities, allowing for more open floor plans.

How do Posi-Joists differ from traditional joists?

Posi-Joists have a unique web design that accommodates services like plumbing and electrical wiring without the need for drilling.

How far can Posi-Joists span?

The span can vary, but Posi-Joists are designed to accommodate longer spans than traditional joists, usually between 4 and 10 meters.

How much do Posi-Joists cost?

Posi-Joists cost from around £25 ex VAT to over £200 ex VAT per joist.