Your roof is made up of several different layers of materials and components that work together to protect your home from the elements. While every material is required for a healthy and complete roof system, one of the most crucial is roof decking. It’s the foundation for your entire roof system.
At Red Diamond, we like to take the mystery out of roofing and walk our customers through a thorough explanation of their roof so they can make informed decisions and feel secure in their roof. Here’s everything you need to know about roof decking.
Roof Decking – What Is It?
Roof decking, also known as sheathing, is the wooden boards that make up the foundation of your roofing system. It lays on top of the structural components of your attic (joists and trusses) to cover the rafters and support the weight of all other roofing materials. Roof decking provides a flat surface to which roofing shingles can be fastened.
In residential roofing, sheathing is typically made from flat sheets of wood, usually plywood or OSB. Oriented Strand Board (OSB) is the most common type of roof decking used on residential roofs today. It is made up of intertwining wood chips or strips that manufacturers bond together using a waterproof resin to form a flat 7/16” sheet. OSB is more popular because it is readily available, durable, and relatively inexpensive.
Construction-grade plywood is made of thin layers of wood glued together. While a bit more expensive than OSB, plywood is much denser and provides better protection against moisture.
What is the Purpose of Roof Decking?
Although you can’t see it, roof decking is an incredibly important part of the roofing process. It provides the foundation for all other materials and protective membranes, such as shingles, underlayment, and flashing can be applied.
Roof decking, therefore, must be strong enough to hold the weight of other roofing materials and durable enough to cope with its constant use and the stresses of the elements.
Signs Your Roof Decking Isn’t Properly Installed
Roof sheathing is also essential to your home’s structural integrity. And if it’s not properly installed or is damaged and unable to support the roof’s weight, it can cause serious structural problems. Here’s what poor installation looks like:
Installing Materials on Wet Deck After a Rainstorm
Roof decking should not be blacked out right after a rainstorm, as it needs time to dry. Installing the water barrier and shingles before the boards dry out entirely leaves the wood vulnerable to rot and damage. Roofers need to cover sheathing when it rains or wait for it to dry out to prevent the risk of mold growth and premature failure.
Buckling or Blown-Off Shingles
Putting a roof covering on a damaged or poorly installed decking risks more damage to your home over time. Roofing shingles, for instance, won’t lay flat or function as well as they should. This may cause water to pool in sagging areas, leading to leaks and water damage. This will significantly decrease the lifespan of your roof.
If roof decking is soft or damaged, fasteners and nails used to install shingles won’t hold. With this, they can easily buckle or get blown off. You can lose entire sections to gravity or high winds.
Not Allowing Proper Spacing
Plywood and OSB sheets expand and contract as they adjust to their environment (humidity, moisture content of the building, and rain). Unrestrained by framing and fastening, panels can move about 1/8 inch as they acclimatize.
Proper spacing between panels allows framing to absorb most of the expansion. If the panels are jammed tightly together, the expansion may result in unevenness or buckling.
Sagging Rooflines
A dip or curve on the roof could be associated with roof decking which should have been replaced. Soaked or rotting decking can warp, leading to a wavy or bowed roofline and ceiling.
Repair or Replace Roof Decking?
If damage is caught in its early stages, it’s possible to only replace the damaged sections. There’s no need to preemptively replace the whole thing if the sheets are not waterlogged.
However, if the damage is extensive or out of control, you have no other option but to replace all of your roof decking. The longer you go without replacing damaged roof sheathing, the more problems it can create. Some of the problems include mold and mildew, water-damaged electrical systems, waterlogged framing and joists, stained drywall, and costly repairs.
If new sheathing is put on improperly (starting at the top instead of at the bottom) or the sheets don’t join properly because of poor installation, you may need to have a roofing contractor fix the problems before your roof is exposed to damage.
When it’s time for a roof replacement, be sure to ask your roofing contractor about the condition of your roof decking. Hire a reputable local roofer and budget for the best quality materials to ensure the longevity of your home’s roof.
Red Diamond is your best choice in residential roofing contractors in the Denver and Fort Collins area. Contact us today for an experience that is friendly, accessible, transparent, and high-quality.
