Small homes can simplify your life, allowing for more time and resources to focus on things that matter. I-joists provide the same simplicity for your home’s structure. Using engineered I-joists in place of traditional lumber framing shrinks the material list and allows for greater spans in your floor joists. But how can a manufactured product trump the natural strength and durability of wood? By design, of course.
What Are Engineered I-Joists?I-joists are made from wood flanges and an OSB web, manufactured to fit together and form a strong, resistant framing material. Designed back in 1969, engineered wood framing is commonly used for floor joists, but can be used for roof joists as well.
I-joists and open web trusses are both manufactured building materials. Unlike open web trusses, which cannot be altered post-manufacturing1, engineered I-joists can be custom cut to your project. This feature makes them attractive to builders and DIY enthusiasts alike, since I-joists allow for flexible and dependable design.
What Engineered Products Offer That Traditional Lumber Can’t
The main benefit that I-Joists offer is optimum strength and load bearing capabilities. Traditional lumber contains knots and other natural properties of wood. These weaker points can cause deterioration and load-bearing failure, which is why joists and beams made from solid traditional lumber must be spaced closer together and cover shorter spans.
Engineered I-joists eliminate the problem of knots and natural weak points. Finger-jointed flanges reduce the tendency to bend and resist deflection, while the OSB web withstands sheer. These characteristics make it much safer to use I-joists over long spans on your floor and in roof structures. Engineered members have the capacity to handle more load, meaning the allowed joist spacing increases.
In both of these instances using engineered I-joists in place of traditional lumber can significantly cut down the materials required for your project. Fewer materials to put up also reduces the installation time, and therefore the overall cost. Engineered lumber may carry a higher price tag, but you need to consider the total investment and take into account the reduced labor requirements.
Are Engineered Joists an Environmentally Friendly Choice?
I-joists also present significant advantages in terms of sustainability. Traditional lumber requires tall trees that are relatively straight – whereas engineered lumber can make good use of the limbs and tops of trees, pieces that were often left to rot after the logging process was complete. Instead of being wasted or composted into the forest floor, these valuable elements of the tree are used in forming the OSB web. Some I-joist manufacturers use laminated lumber for the flanges, which also makes use of the logging leftovers.2
The manufacturing process behind these products is also eco friendly, with very little waste involved. Cutting back the amount of lumber required to frame your home is also a sustainable, responsible choice.
I-joists have lower levels of moisture, reducing the chance of shrinkage, splitting, warping, bowing and twisting. Contractors like to install this material, since it results in fewer call backs. For reliability, these engineered products stand above traditional building materials.
Where Can You Use I-Joists In Your Home?
Engineered I-joists come in much longer lengths than the traditional 16-foot framing lumber. No more wishing that trees grew beyond that magic number, now you can invest in engineered lumber that spans your entire main floor and covers the slope of your roof without a problem.
I-joists can be cut to the desired length and used to create stable, dependable framing on every level of your home. Some builders even prefer using I-joists for floating homes, in place of concrete slabs. I-joists are must easier to adapt and repair than a large concrete slab, and provide the same level of load bearing capacity.
Traditional lumber still has its place in house framing, but the advantages of engineered I-joists are gaining ground. As the price levels even out you’re bound to see even more builders depending on the strength and structure of engineered building products.
1. LP Building Products, Why Choose I-Joists Instead of Other Products?, Retrieved on February 14, 2011, http://www.lpcorp.com/LP_Products/Floors/SolidStart_I-Joist/Why_Choose_I-Joists_Instead_Of_Other_Products_/
2. Gray, Jody, I-Joists: Engineering a Better Floor System, Vol. 04-4, Retrieved on February 14, 2011 from Appalachian Hardwood Center at http://ahc.caf.wvu.edu/joomla/index.php?option=com_remository&Itemid=148&func=startdown&id=76.