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Sheathing is the outer layer of stucco in a cladding system. It is typically plywood or densglass that provides protection and insulation to the building’s exterior wall surfaces, such as its side walls, back wall and roof.
Plywood and densglass sheathing are two types of exterior wall sheathing. Plywood sheathing is made from untreated wood planks with spaces between them which allow for airflow behind it.
Densglass is made from densified glass fibers with an acrylic binder and a thin aluminum coating to reflect heat. Densglass sheathing is an exterior gypsum sheathing that provides a coarse, firm surface for the attachment of cladding to walls and ceilings.
Densglass has been around since the 1930s and it’s still going strong today. Plywood, on the other hand, came into existence in 1928, so densglass is a more established product with proven performance for over 80 years.
Both densglass and plywood are made out of wood fibers glued together under high pressure. Densglass does not use any formaldehyde. Unlike plywood, densglass contains up to 20% formaldehyde glue. If you’re not sure which one to use, this blog post will help.
Densglass sheathing vs Plywood: What’s the Best Choice for You?
This blog post has discussed the benefits of each product, how they compare to one another, and when you might use them.
Finish Options
Densglass also has a high-quality surface finish over plywood, which is not as attractive. Densglass sheets are denser than plywoods because densglass contains fewer voids between wood grains.
Winner: Densglass sheathing
Cost:
The cost of densglass sheathing is less expensive than plywood but this investment will last the homeowner much longer without needing replacement. Densglass doesn’t need to be painted or sealed like plywood. So it is cost effective using Densglass sheathing over plywood sheathing.
Winner: Densglass sheathing
Color protection:
Dyed densglass sheets have a durable protective coating that resists fading or ultraviolet rays – meaning you will not see the color fade as with other materials like wood products in natural light conditions. As opposed to, plywood will fade in natural light conditions.
Winner: Densglass sheathing
Durability:
Densglass is more durable than plywood because it impedes damage better and can withstand harsh weather conditions without breaking down as quickly.
Winner: Densglass sheathing
Ease of installation:
Densglass is installed by professionals while plywood can be self-installed due to its low construction complexity and ease of installation.
Winner: Plywood
Water Resistance:
Densglass provides superior protection from water intrusion when exposed to long periods of moisture or humidity. On other hand, plywood will become soft and can start to warp or crack if exposed to prolonged moisture.
Winner: Densglass sheathing
You Can Also Check: The Ultimate Guide To Storing Plywood For Beginners
Weight:
Densglass is denser than plywood, which implies that densglass has a higher weight per square foot (PSF) – meaning densglass sheathing will be heavier than plywood.
Winner: plywood
Longevity:
Densglass sheathing lasts longer than plywood. So you don’t have to be so worried about the chance of densglass being exposed to extreme temperatures.
Winner: Densglass sheathing
Air Leakage:
The denser nature of densglass means that it will slow air leakage through cracks to a greater extent when installed with other insulation products on exterior walls.
Winner: Densglass sheathing
Fire resistance:
Densglass sheathing is a fire resistant panel and can withstand temperatures up to 750 degrees Fahrenheit.
Winner: Densglass sheathing
Fire Resistance Rating:
Densglass has the highest rating for fire resistance, which means it will resist extreme heat in case of an accidental fire.
Plywood does not have a designated class or ranking when considering its resistance to fires – meaning there are no industry standards as opposed to densglass panels that meet F-class ratings (highest).
Winner: Densglass sheathing
Eco friendly:
Densglass is a natural and environmentally friendly product. Because there are no harmful chemicals in densglass panels when compared to plywood’s chemical content that off gases from the wood during its production process.
Winner: Densglass sheathing
Corrosion:
Densglass is corrosion resistant and does not corrode as quickly as plywood.
Winner: Densglass sheathing
Applications:
Common Uses of Densglass: Densglass is a waterproofing product. It is specifically designed for roofs, gutters, and drywall sheathing. Densglass is one of several products for roofing sheathing.
It is known as “membrane” or “coating” materials. Densglass sheathing is often used in the construction industry for protection and sound insulation.
The material can be applied directly to the surface of a roof by rolling it on or spraying it on with an airless spraying system. Common uses for densglass sheathing include protecting structures from environmental damage and covering roofs.
You Might Also Like: How to Cover an Existing Deck with a Roof?
Common Uses of Plywood: Plywoods are typically made of gypsum wallboard panels with glue between them for added strength and stability. The boards used can be solid timber planks, oriented strand board (OSB), hardboard sheets, or chipboard sheets.
Plywood is an often used material for exterior wall sheathing. It also can be installed on the interior of a building as house frame sheathing, subfloor sheathing, or underlayment. Plywood will most likely be used in a project if you’re working with classified lumber that must meet plywood performance requirements.
Winner: Both
Overall, densglass is the better choice over plywood. So the ultimate winner is densglass sheathing.
Conclusion:
Densglass sheathing and plywood are both building materials that can be used to protect your home. They offer different benefits, so it’s important to understand the differences between them before making a decision on what product you want for your specific needs. We hope this article on the differences of densglass versus plywood helped you decide which type suits your needs best.
I have an existing exterior wall already and the wall is kind not nice. Can I just put densglass over without removing the old plywood or removing plywood then install densglass? What do you recommend.
You can use it over your old plywood. 🙂
Thank you very much….
Is 5/8 x 4 x 8 or 1/2 x 4 x 8 DensGlass® Exterior Sheathing ok to use for my homes exterior wall sheathing instead of OSB?
I guess is the gold DensGlass® Exterior Sheathing considered structurally and as strong as 1/2 OSB to meet building codes. Thanks Shawn
Yes, it is fine. 🙂
Thank You. I have one more question does the DensGlass® Exterior Sheathing have the shear ratings to resists wind loads and resist racking to keep walls upright like the OSB.
For this reason, it is better to discuss with the manufacturer according to your needs.
Plywood is soooo expensive these days. How would densglass do for flooring? I would like to use it in place of plywood as a substrate to level to floors and proivde a clean surface for either hardwood flooring or luxury vinyl tile.
Your thoughts,
Mike
Yes, you can dens glass for flooring.