Questions for People new to the Engineered Wood Products Industry
1. What is typically called the “Original Engineered Wood Product”?
Glulam beams were used in the first half of the 20th century and even earlier, and are typically considered one of the first engineered wood products. Plywood is a close second.
2. What is FSC and how does a wood product become FSC certified?
FSC stands for “Forest Stewardship Council”. This is a certification program that promotes environmentally sound forestry practices and includes a chain of custody from the forest to the supply chain. The intent is to verify that best practices have been used during the harvesting and manufacture of the EWP. Not all EWP is FSC certified. Only participating companies can claim FSC certification. First, the forestry and manufacturing process must be reviewed. All or only a portion of production can be used for participation in the program. Key to the certification process is a chain of custody verification that must include participation from the final link in the distribution chain. Anything from a matchstick to an I-joist can be FSC certified.
3. Are EWP used for outdoor or indoor construction?
EWP are only rated for dry use. Dry use is typically an enclosed structure where the equilibrium moisture content reaches less than 19% shortly after the building is enclosed. Exceptions can be made for EWP installed in a controlled condition, such as covered porch where it has been clad with aluminum flashing or other means that keeps out moisture but still allows the wood to “breathe”.
4. What is crowned I-Joist?
I-joists and LVL are not produced with camber. If it is crowning upward, it is most likely due to an improper installation. This can be caused by interior partitions that are not at the same elevation as exterior walls. If the I-joist is crowning before it has been installed, it may be because it got wet and it should be evaluated before it is installed.
5. What are material safety data sheets (MSDS) and where do they come from?
Manufacturers maintain safety data sheets to inform the public of possible health hazards associated with their product. As of July 15, 2015, the “MSDS” format is required to be in the new “SDS” format.
6. Do mold & mildew compromise the integrity of the EWP?
Most black mildews do not, but many molds do. “White” mold is typically a sign of a mold that can cause strength loss, but other molds may also cause strength loss. It is usually not practical to determine exactly how much strength has been lost and estimates of the strength of a compromised structural member may be unreliable. In some cases, the health concerns are more immediate, and remediation can involve removing the affected wood. Mold and mildew require moisture to grow, so the best way to avoid them is to avoid situations where the wood can get wet, including unvented crawlspaces and roofs, close proximity to the ground, etc.
7. Are there cutting instructions or parameters for cutting into the OSB of an I-Joist?
Yes. IB literature has web hole cutting guidelines. IB software can also be used for more specific span and load conditions and can sometimes produce more favorable results.
8. Do we offer a guarantee for our product? If so how long is our guarantee good for?
Yes, we guarantee our products for the life of the structure, as long as it was properly installed. See our written guarantee for more details.
9. What is the difference between an I-Joist used in a residential building verses a commercial building?
The I-joist itself is the same. Commercial buildings typically have heavier design live load requirements, and can require deeper and stronger I-joists. For example, an 11 7/8” deep 20’ span I-joist can support 40 psf design live load, but that same I-joist installation may not support 50 psf, 100 psf or more required for some commercial applications. IB has span tables in our literature and software for checking less common design loads and span conditions. The I-joist must be evaluated for the correct design load for the intended application.
10. Does EWP meet the requirements of the fire code?
The short answer is yes. EWP are manufactured with heat resistant adhesives and are approved for use in both protected (sprinklered) and unprotected (unsprinklered) construction. The answer to how much fire protection is required depends on the building use, classification, and size requirements of the building code. Unless EWP is installed in a building that is classified under the building code as non-combustible, some form of fire protection is required. Residential one-and-two-family dwellings may require ½” gypsum board ceiling or other approved equivalent fire protection, but there are exceptions. For one and two-hour fire-rated assemblies, additional layers of gypsum board and/or insulation may be required.
11. What kind of technical help do we provide if a problem occurs after the I-Joist has been installed into a structure?
First, your local IB sales representative should be contacted. In many cases, installation problems can be identified and corrected quickly. For damaged I-joists or installations requiring further analysis, IB has an engineering staff that can offer advice and provide repair instructions if needed. Repair engineering is limited to the EWP IB manufactures and distributes.
12. What are the differences between the series of IB I-Joists available for sale?
IB400 and IB600 are made with 2×3 lumber flanges. The only difference is that IB600 uses stronger rated lumber and thus, has somewhat longer span capabilities. IB800 and IB900 are made with 2×4 flanges. The IB900 uses a stronger rated lumber and also has a thicker OSB web. These two differences allow for somewhat greater spans than IB800. IB800 is available in depths up to 20”, whereas, IB900 is available in depths up to 24”.