Wood glue is a common household adhesive that is specially designed to weld wood products and surfaces together. You can use wood glue on all manner of home design and improvement projects. It's an extremely versatile adhesive that is easy to find and work with. If you're working on a project that will be exposed to rain or moist environments, you might be concerned about its water-resistant properties. Do you need special waterproof glue, or will wood glue stand up to water and not break down?
Most wood glue products have some level of water resistance but should not be exposed to wet conditions over long periods of time. Some wood glue manufacturers have special versions of their glue that are certified as fully waterproof. You should pick the right wood glue for your project based on how much moisture you expect it to be around.
Continue reading to learn more about what affects a wood glue's water resistance and which glue to use on your project.
Stick to the Standards
To prevent consumers from being confused by marketing, manufacturers can obtain a wood product water resistance standard. You should pay attention to this rating as it is the best indicator of how waterproof wood glue is. The two waterproof certifications are ANSI/HPVA Type 1 and ANSI/HPVA Type 2. Type 1 is guaranteed to be almost entirely waterproof under all circumstances. Type 2 is considered water-resistant in most cases but would not stand up to constant moisture.
For outdoor projects, you should try to find wood glue that is rated as type 1. This glue would withstand being submerged for some time, near-constant contact with moisture, and even sitting in hot water. If you plan to work on a patio project, or some backyard wood repair job, it would be best to rely on something that you can be more confident will withstand the elements.
For most all other uses, regular wood glue rated at type 2 will work perfectly. Most wood things are not exposed to water anyways since they have to receive special coatings not to start getting damaged in the first place.
For a long time, wood glue was considered weak when exposed to water. Some cheaper wood glues will still start to dissolve if submerged in water for some time. Modern manufacturing and glue formulas have made it so that almost any kind of glue can be made to varying levels of water resistance. It is really up to you to find the right adhesive for your project.
Is Wood Glue Weather Resistant?
Most common name-brand wood glues have some level of weather resistance. Type 2 glues should do find with moderate levels of rain but may not stand the test of time. The ANSI/HPVA test for type 2 glues includes submersion in water for several hours, repeated over some cycles. If the glue bond can withstand this type of testing and not dissolve, it should be sufficiently weather resistant for most projects.
Does Wood Glue Last Outside?
Wood glues will last outside as long as you use the right kind for your environment. If you live in a temperate place with not much rain, then regular wood glue would work. Meanwhile, if you live in a warmer and stormier climate, it may be better to go with a type 1 glue to be safe. When your project also requires tile work, you can read this article for help picking the best glue, 3 Types of Tile Glue To Know.
Not just water, but the temperature is also a consideration as to whether a glue will hold up over time. Heat can often break down a glue bond and weaken it. Hot, humid areas are the worst for glue because they can effectively "melt" the glue and cause the glued joints to shift and slide around. Type 1 glues are tested to withstand being submerged in boiling water for hours on end, so they are best suited for extreme circumstances.
How Long Will Wood Glue Hold Together?
Once wood glue has cured and is no longer workable, it creates a powerful seal that is almost impossible to destroy without the right tools. Modern glues have very high bonding power and will likely outlast anything you can make with them.
It isn't easy to approximate how long specialized wood glue will hold together because it hasn't been around long enough to come apart. If undisturbed and not exposed to corrosive elements, the bond would last for an indeterminably long time.
What's the Strongest Wood Glue?
Many woodworking enthusiasts and contractors alike will agree that Titebond III Ultimate wood glue is the best of its kind. This wood glue boasts ANSI/HPVA Type 1 and is entirely waterproof. It also has 4,000 P.S.I of adhesive force, which is very high. This would likely be the best choice for the absolute strongest hold and the highest level of waterproofing available to consumers.
It's important to remember that you may not always want the strongest glue but the best one for your project.
Is Waterproof Always the Best Choice?
While being waterproof is a great feature on many wood glues, it may not be necessary at all in your project. Waterproof glues can be workable for less time and less forgiving of small mistakes. Some wood glues also rely on their ability to be removed with solvent for easier repairs down the road.
Type 1 extremely strong wood glues might not be removable at all without some destruction to the project. The waterproof abilities of the adhesive should be central to the project to justify using glue like that.
Is Gorilla Wood Glue Better than Titebond?
Gorilla glue is polyurethane-based, while Titebond uses an aliphatic resin formula. Gorilla glue will adhere to more kinds of things and fill gaps better, but Titebond will create a stronger wood-to-wood bond. Another benefit of Titebond is that it cleans up with water before curing. That means if you make a mistake or get some on your hands, it is much easier to clean off.
If you are working on a purely wood-based project that requires the strongest adhesion possible, Titebond is better. Gorilla glue's main benefit is in its versatility. If you've been wondering how long you have before wood glue sets in place, check out our article, How Long Does It Take Gorilla Glue To Dry?
Waterproof When Needed
As we've seen, almost all modern wood glues provide some acceptable level of waterproof adhesive power. It's up to you to decide on what objectives are most important. More waterproof glues dry up faster and are more difficult to fix problems with. Less water-resistant glues can be easier to clean off and will withstand most normal conditions. Find a product that fits the needs of your project!