Think Twice Before Discounting Cover Boards

By Lauren White, RCS Assistant Editor. 

This overlooked product will increase your roof’s lifespan. 

As someone new to the roofing industry, I had never heard of cover boards until now.  And it turns out, they’re really important to help protect the longevity of the roof.  However, they’re often excluded because they require more money and additional time to install.  The benefits of using cover boards far outweigh the costs though!   

What is a cover board exactly?  It’s a thin substrate, which is an underlying substance, that the roof membrane is then adhered to.  Cover boards are different than regular substrates and help to extend the life of a roof.  Many types of cover boards are suitable for a variety of applications.  Most common types are: gypsum fiber, gypsum, cement, wood fiber, high-density insulation, perlite, asphaltic and mineral fiber board. 

Cover boards are a critical component to the roof and add durability and protection.  And if you need more convincing to use cover boards, they also protect the roof from external fire by acting as a fire barrier, guard the insulation from hail damage, and increase the wind uplift with fewer fasteners.  The concept of wind uplift is new to me also.  This phenomenon occurs when there’s a difference in air pressure above and below the surface of the roof.  There are a couple of ways this can happen, the most common are when, “...pressure above the roof system decreases by high airflow (wind) or pressure increases inside a building from air pressure buildup,” USG explains.  This buildup inside is caused by air flowing in through any cracks or openings in the house.  This is detrimental for a roof and can cause shingles and other materials to be torn off. 

Certain buildings require the use of cover boards on the roof.  Derrick Hutchinson, Product Manager for USG Roof Boards, shares in an interview, that you need a cover board, “...if your building requires a fire rating, in coastal regions that may experience hurricanes and would need elevated wind uplifts, and also in hail regions where the hail can actually puncture the membrane and damage the insulation below.”  Additionally, the National Roofing Contractors Association (NRCA) has endorsed the use of cover boards in all low-slope roofs.   

Cover boards are constantly going through iterations to improve their quality and performance.  More and more information is being collected about roofs and the damage a storm and normal maintenance can cause to them.  As a result, cover boards are being made with attributes to increase their strength and extend the roof’s lifespan even more.  Building codes have impacted the innovation of cover boards too with the demand for higher fire and wind uplift performance.   

Different types of cover boards help protect against different threats and potential damages.  USG has a variety of roof board options that will fulfill the demands of any job.  Founded in 1902, this company is dedicated to offering products builders trust.  Their USG Securock® Brand High-Performance Roof Boards provide you with five different options depending on your needs:  

1. Gypsum-Fiber: Typically used for fully adhered and mechanically attached systems.  It has a strong bond, low surface absorption, great wind uplift ratings, and is made of 97% recycled materials. 

2. UltraLight Glass-Mat: Ultra light is in its name for a reason since it’s lighter than other glass-mat roof boards made by competitors.  This board is designed for mechanically attached systems and has a tighter mat, resulting in less itchiness.  For fire barrier applications it has an unlimited slope. 

3. Cement: According to USG, it is the “Lightest cement roof board in the industry.”  It is fireproof, easy to cut and fasten, and is great for liquid applied systems.   

4. Gypsum-Concrete Patch: Durable, fast-setting, and a quality patch solution for poured roof decks.   

5. UltraLight Coated Glass-Mat: This cover board is extremely strong while still lighter than competitor glass-mat roof boards.  Easier to handle and cut due to its tighter mat, it is designed for mechanically and cold-applied adhered systems.  It also has less itchiness and an unlimited slope for fire barrier applications. 

While there are many factors to consider when designing a roof assembly, and one added step might be a nuisance, using cover boards will be very worthwhile.  Contractors are able to build durable and lasting roofs with the use of cover boards.  They protect roofs and insulation from high winds, catching fire and being penetrated by hail.  For all these reasons, buildings are safer, less flammable, more secure and energy efficient.  Cover boards are a critical component, leading to an extended, and impressive, roof lifespan.  Consider adding cover boards into your next roof assembly plans! 

Learn more about roof cover boards and USG Roofing Solutions. 

Have a question? AskARoofer. 

Find your local roofing contractor in the RoofersCoffeeShop® Contractor Directory. 

About USG Corporation 

USG Corporation is an industry-leading manufacturer of building products and innovative solutions. Headquartered in Chicago, USG serves construction markets around the world through its Gypsum, Performance Materials, Ceilings, and USG Boral divisions. Its wall, ceiling, flooring, sheathing and roofing products provide the solutions that enable customers to build the outstanding spaces where people live, work and play. Its USG Boral Building Products joint venture is a leading plasterboard and ceilings producer across Asia, Australasia and the Middle East. For additional information, visit www.usg.com.