I-Joists - Frequently Asked Questions

What are I-Joists?

Steico I-joists are an engineered solution for floor joists, roof members and wall studs. They are fully engineered, and factory produced to give uniform strength, rigidity and weight, out-performing traditional solid wood construction. Steico joists have an LVL flange and high quality HDF (high density fibreboard) web which has a high strength to weight ratio and therefore produces lighter, longer spans combined with quick and easy installation, reducing your build time and increasing efficiency. I-joists are produced under strict quality control, so that natural imperfections are non-existent.

Where can I-Joists be used

Joists are most commonly used in floor applications but can also be used for walls.

How do I-Joists work?

Because I-Joists are linear engineered products, they eliminate the natural defects and the need for over-design. An I-joist has two main parts, the web and flange. The web is sandwiched between a top and bottom flange, creating the “I” shape. I-Joists work similarly to traditional joists but come with an extensive list of benefits.

What are the benefits of I-Joists?

• Reduced thermal bridging
• Longer spans achievable
• Dimensionally stable
• Lightweight
• High load bearing capacities
• Easy installation of services
• Easy to use with standard woodworking tools

• Preliminary calculation & extensive planning documents

What Fixings and Fittings do I need for I-Joists?

Where a design is necessary for your I-joists, it will include a full material list for everything required to fit the floor joists. This will include everything from hangers, to noggins, to restraint straps. All materials required will be designed and supplied as part of your order. Incorporating the material list within the design saves time during the installation process as the joist will be supplied as a complete package, so all joists will be cut to length as standard, and fixings provided excluding nails/screws.

When do I need to use Joist Hangers?

Joist hangers will need to be used when a load is being distributed from one joist to another. Masonry hangers will also be required when a joist meets a masonry wall. The number of hangers required, and where they will be required, will be included on your design.

Why should you use I-Joists rather than traditional joists?

As well as providing virtually no shrinkage, eliminating the annoyance of squeaky floors, I-Joists are much easier and quicker to install, given that joist packages are designed and produced to your unique project – a great solution for those with time constraints.

How much more time and cost effective are I-Joists?

The "Timber Joist vs I-Joist" infographic below shows the material and time saved by using I-Joists based on an example floor drawing. The number of joists required is less than half with no need for washers and bolts, and a 75% reduction on the number of hangers needed when compared with using timber joists. This saving is further reflected in the install times, a good reason why an increasing number of builds are using I-Joists.

How much experience do Alsford have with I-Joists?

In short - a lot. Engineered Wood Products design and supply is a dedicated division within Alsford, delivered by an experienced team. This in-house team work with self-build home owners, through to National Housebuilders, providing the design, and supply of the high quality I-Joists you need for a secure build. Alsford also retain qualty control over our production, with our I-Joists produced at our mill in Dartford, Kent, overseen by an experienced Quality Control Manager.

How do I order I-Joists from Alsford?

To discuss your I-Joist order, including provision of a design, and materials list, please contact [email protected]

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