Is Your Roof Deck Properly Spaced Out?

January 11, 2021

Is Your Roof Decking Spaced Out On Your Home In Colorado’s Front Range?

One of the structural components of your roof that Thorton, Colorado-based roofing company specialists Roof Worx thoroughly inspects is your roof decking or roof sheathing. If you have ever heard the old adage “the basis of a good home is a strong foundation,” know that this also applies to your roof system and the roofing materials utilized. A quality roof replacement in Colorado’s Front Range begins with a solid foundation which is the roof decking/roof sheathing.

Roof decking or roof sheathing is the lumber (wood boards or roof boards) attached to the roof trusses of your home. This is the roofing material to which your roofing shingles are nailed. Without a good, solid roof deck in which to nail the shingles, problems are sure to arise when the first big windstorm occurs.

Types of Roof Deck/Roof Sheathing: The Groundwork of Your Entire Roofing System

There are basically (3) types of common roof decking.

Roofer installing solid roof sheathing

SOLID SHEATHING BOARDS – Most new homes built after the mid to late 80s typically have solid roof sheathing. This sheathing is typically ½” to 1″ CDX plywood or OSB (Oriented Strand Board) and comes in 4’x8′ sheets. This type of substrate creates an excellent surface for properly nailing shingles, including asphalt shingles. Homes with solid roof decking are commonly found in newer housing developments such as some of the ones in Highlands Ranch, Commerce City, Superior, Broomfield, Thornton, and Castle Rock. During the tear-off process of a re-roof or roof replacement project, our project managers and crew are well trained to identify any potential issues with the roof decking such as delaminated or deteriorated decking which would require replacement in order to provide a proper nailing surface.

Interior of plank decking of a roof

PLANK DECKING – In older homes, plank decking may have been used for the roof decking (substrate). Typically, plank decking material is either 1″x 6″ or 1″x 8″ lumber. Again, if this type of decking is discovered during the tear-off of the roof shingles, a thorough inspection must be made to make sure that it is in good overall condition and that the gaps between the individual boards do not exceed ¼” to ½”. Most shingle manufacturers do not warrant their product if it is installed on planks that exceed 1″x 6″ or have gaps in excess of ¼”. In addition, many building departments have very specific requirements concerning the gap between planks in order to allow a new roof to be installed over plank decking. Roof Worx encounters this type of roof decking on a regular basis and knows what to look for and what local building officials require.

Roofers installing skip decking for a roof

SPACED OR SKIP DECKING – Many older homes in older neighborhoods may have spaced or skip decking. This is typical decking found on homes that originally had cedar or wood shakes installed. This type of decking is identified by wooden boards running horizontally to the rafters with a 4″- 6″ space between them. It is still acceptable to use this type of substrate if new wood shakes are being installed, however, if the re-roof is going to be made with any type of asphalt shingles, the substrate must be new, solid sheathing consisting of either OSB (oriented strand board OSB) or plywood. Typically, if a new substrate is required, it is simply installed over the existing spaced decking. An experienced inspector, like our Haag Certified Inspectors, considers many factors when inspecting a roof as it relates to potential decking issues. They also look for evidence of plank or spaced decking from open soffit areas or, in some cases, complete an inspection of the attic space to determine what type of roof decking exists.

Other Functions of Roof Sheathing/Roof Deck

Sheathing of a residential roof

Roof sheathing’s primary function is to strengthen your roof. It provides a strong foundation for the rest of your roof system. It also helps in other key areas, including:

Preventing Leaks

Roof sheathing panels were not always used when asphalt shingle roofs were first constructed. The majority of homeowners discovered that without sheathing, roofs were much more prone to leak. While today’s asphalt shingles include a variety of weatherproofing treatments, the additional layer of wood boards provides a roof with more protection from the elements. Because many sheathing boards are also weather-proofed, they help to extend the life of your roof and protect your home from water damage.

Strengthening And Supporting Your Roof

Roof sheathing aids in the even distribution of weight across your roof. Because roof sheathing panels are attached to your roof’s trusses and joints — its strongest supporting beams — they help prevent bowing and sagging caused by heavy loads of snow and precipitation. They also aid in the retention of asphalt shingles on your roof. Roof sheathing helps ensure that any weight added by shingles is distributed evenly across the span of your roof. Shingles can be a little heavier than you might think, and sheathing helps ensure that any weight added by the shingles is distributed evenly across the span of your roof.

Preventing Fire

Roof sheathing or roof decking can help in fire prevention. While nothing is completely fireproof, many roof sheathing materials include a fire-retardant treatment that can aid in the prevention of fires on the roof or in the attic.

How Do You Know You Need New Decking Material?

Interior of attic showing roof decking

There are a number of red flags that will alert you to whether or not you need new roof sheathing and roof framing:

  • If you can clearly see broken sheathing boards, it’s time to replace them. This may happen when a large amount of weight is concentrated in one area, such as when a tree branch or limb falls on the roof. It can also happen over time if your roof has reached the end of its useful life. Broken sheathing is easy to spot because your roof will most likely sag, and you may even notice sawdust and broken parts in your attic.
  • Your roof may have been damaged by water. Look for leaks, puddles, or water stains in the ceiling. If you spot any of these, it’s time to replace the wooden boards. Water damage to the sheathing of your roof is especially dangerous because it can compromise the structure of your roof.
  • If you notice rotting parts of your roof’s sheathing, it’s time to re-roof. Water damage is the most common cause of rotting sheathing, but it can be less obvious if you haven’t yet noticed leaks.
  • Check for rotting sheathing by heading up to the attic. You should be able to see darkened spots in the wood if the sheathing has begun to rot in places. If your attic isn’t too high, you can also go around gently with a hammer or even your hand, feeling for soft spots in the wood.
  • If you can see light passing through holes in your roof with a flashlight in your attic, it’s time to call a professional roofer. Water will be able to pass through if light is visible.
  • Sagging in your ceiling or roofline is the most obvious sign of roof sheathing damage. While in your home, if you notice that some areas of the ceiling appear to be closer to you than others, the sheathing could be the culprit. If you can see from the outside that parts of your roof are sagging, call a quality roofing contractor.

Roof Worx: Assisting You With All Your Roofing Needs

Serving the entire Front Range communities, from Ft. Collins to Colorado Springs, your local Denver roofing contractor, Roof Worx, can assist you with all of your roofing needs and roof deck. Our team of expert professionals can make sure that your roof is expertly installed from a solid foundation through the finished product.

For more information on any of your roofing, siding, gutter, or installation needs, contact Roof Worx, your Denver roofing experts at (303) 353-1825. Roof Worx, Thornton, Colorado.

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