Masonite® Engineered I-Joists

Masonite® Beams comprise of high grade white wood flanges combined with OSB webs offering a superior strength to weight ratio. Masonite I-Joists carry the ETA certification and CE marking and are manufactured in accordance with the requirements of ISO 9001 and the environmental standard ISO 14001.

Features & Advantages

Engineered for long Spans – Engineered for strength the I Joist gives greater design freedom to create larger open areas in rooms without having to use steel beams which can’t always be hidden in the floor and can prove unsightly.

Engineered for quality – The use of ULTRA-LAM as the flange material avoids the inherent problems that plague floor joists such as shrinking, twisting, cupping and bowing, all of which contribute to squeaking floors.

Services – Service holes can be easily drilled in the OSB web to accommodate services (please see technical guide for details)


Complementing the Masonite Joist is the ULTRA-LAM® range. Used as an alternative to steel in floors ULTRA-LAM® comes in depths to suit any Masonite Joist. Being able to fix timber to another engineered timber product instead of using steel reduces trades, cost and time as all necessary supports can be done by the carpenter fitting the floor.

Manufactured by bonding high-specification rotary peeled timber veneers to create huge billets of engineered wood, ULTRA-LAM® is one of the strongest and most reliable engineered wood products available in the Ireland & the UK today.

Available in a wide range of sizes, ULTRA-LAM® is an excellent partner for Masonite® Joists in the SIMPLE FRAMING SYSTEM® and can also be used for a variety of purposes including floor and roof beams, lintels, purlins, columns, studs, door stock, and more.

View Masonite Floor System Guide