Long clear spans
Fewer supports and more freedom in the layout of the rooms below.
Products
I-Joists
At Donaldson Timber Engineering, we design all of our I-joist flooring systems using Finnjoist.
02 / DETAIL
At Donaldson Timber Engineering, we design all of our I-joist flooring systems using Finnjoist.
I-joists are the most common way to structurally frame an upper floor in a residential building. I-joists are also commonly used in flat roofs for both residential and commercial buildings. At Donaldson Timber Engineering, we design and cut all of our I-joist flooring systems using Metsä Wood's Finnjoists.
Finnjoists are manufactured using OSB for the webs and Kerto LVL for the flange material. This results in an I-Joist designed to provide an efficient, lightweight and dimensionally stable engineered floor solution, with improved dimensional stability compared with conventional solid timber joists.
Finnjoist material is sourced from environmentally legal and sustainable PEFC-certified supplies
Get in touch with our team to find out more about our expertise with Finnjoist, and how we offer the complete flooring solution.
03 / OSB WEB FLOORS
Straight, stable, long spanning
Metsä Wood Finnjoist I-Joists pair engineered timber flanges with an OSB web to give a light, dimensionally stable floor that holds its line and spans a long way with very little movement.
Dimensionally stable
Engineered sections stay straight, reducing shrinkage, squeaks and deflection.
Light to handle
Easy to lift and fix, delivered cut to a project-specific layout.
I-Joist span drawing / not to scale
CCPI Approved
Our products are CCPI Approved: clear, accurate, accessible, up-to-date and unambiguous product information.
04 / LOADING OPTIONS
Match the joist to the floor
Pick the loading condition for your floor. The clear spans and depths below come directly from the standard options in our quote calculator.
Unsure of the loading? Send the floor plans and our design team will confirm the right specification.
Selected option
Domestic floor
OSB web I-Joist, long clear spans
- Max clear span
- Up to 6.10m
- Depths held
- 220mm · 240mm · 300mm
Price this option
Larger sizes and bespoke designs are available. If what you need is not shown,talk to our design team.
05 / PROJECT INPUTS
Bring the right information
Give us the spans and how the floor will be used and we can design, detail and price the joist layout.
Send project drawings01
Floor plans
Plans and sections in PDF or CAD, with bearing walls marked.
02
Clear spans
Longest clear span, opening positions and any trimmed areas.
03
Loading + use
Domestic, apartment, office or flat roof, plus point loads.
04
Service holes
Where services must pass through, so web openings can be planned.
06 / QUESTIONS
Common questions
Price your floor
Engineered floors, priced in a minute
Use the calculator for standard loading, or send the floor plans for a fully designed joist layout.