Wood Glue 101: Which Bottle Do You Actually Need?
PVA, polyurethane, hide glue, epoxy... The glue aisle is confusing. Let's break down the only 3 types of wood glue a beginner really needs in their shop.
Stop Staring at the Glue Aisle
If you've ever walked into a hardware store and stared at a wall of 40 different types of wood glue, you aren't alone.
Some bottles are yellow. Some are white. Some expand into foam. Some claim to be stronger than the wood itself (spoiler alert: most of them are).
As a woodworker, your joint is only as good as your adhesive. But you don't need a chemistry degree to understand what works. After years of testing nearly every brand and formula on the market, I've reduced my daily-driver glue collection down to just three essential bottles.
Let’s break down exactly what you need, and more importantly, what you can ignore.
1. Standard Yellow PVA Glue (The Workhorse)
This is the classic yellow bottle you see in almost every woodworking shop. Polyvinyl Acetate (PVA) is the undisputed king of indoor furniture building.
Why you need it: It’s cheap, cleans up easily with water before it dries, has a decent "open time" (how long you have to position your pieces before it starts setting), and creates a bond that is literally stronger than the wood fibers surrounding it.
When to use it:
- Edge-gluing boards for tabletops
- Assembling indoor furniture (bookshelves, coffee tables)
- General shop tasks
Always clean up PVA glue squeeze-out with a damp rag before it gets hard, or wait until it turns into a rubbery gel and scrape it off with a chisel. If you let it dry completely, it will ruin your finish!
2. Water-Resistant/Waterproof PVA (The Outdoor Hero)
Standard yellow glue is amazing, right up until it gets wet. If you build a patio chair with regular PVA, a single rainy season will weaken the joints until the chair collapses.
For anything exposed to the elements, you need a Type II (Water-Resistant) or Type I (Waterproof) PVA glue. These are usually branded as "Premium" or "Ultimate" and often come in darker or slightly green-tinted bottles.
When to use it:
- Adirondack chairs and outdoor benches
- Birdhouses and garden planters
- High-humidity indoor areas (like bathroom vanities)
They handle almost exactly like standard yellow glue, but provide the chemical resistance needed to survive morning dew and rainstorms.
3. Polyurethane Glue (The Gap Filler/Expanding Glue)
Polyurethane glue (often recognized by the Gorilla brand, though many companies make it) is a completely different beast.
Unlike PVA glue which dries by evaporation, polyurethane glue cures by reacting with moisture in the air and in the wood. As it cures, it actually expands into a tough foam.
Polyurethane glue expands as it cures. If you don't clamp your pieces tightly, the expanding foam will actually push your joint apart!
Why you need it: Because it expands, it is fantastic at filling small gaps if your joinery isn't perfectly tight. It is also 100% waterproof.
When to use it:
- Gluing end-grain (PVA is terrible at this)
- Gluing wood to non-porous materials (like metal or stone)
- When building projects that will live completely submerged or constantly soaked
The Secret to a Perfect Glue Joint
No matter which glue you choose from the list above, there is one universal rule: Glue requires pressure.
If you just spread glue on two pieces of wood and press them together with your hands, the joint will fail. You must use clamps.
When you apply pressure with a clamp, you force the glue deep into the pores of the wood. The goal is to see a tiny, consistent "bead" of glue squeeze out along the entire length of the joint. That tells you the gap is completely filled and the pressure is even.
Keep It Simple
Start your shop with a single, medium-sized bottle of standard yellow PVA glue. Learn how it behaves, how long it takes to tack up, and how much squeeze-out is normal.
Once you master the basic yellow bottle, you’ll rarely find yourself needing anything else.
Keep your edges sharp,
– Mark