Nails or Adhesives

When it comes to fastening things together, people have been inventing creative ways for centuries. Years ago, they used leaves braided into rope to tie things together. Then, someone came up with the idea to use tapered wooden pegs. Wooden pegs evolved into metal nails (as well as screws, bolts, and staples) that held well, but required making holes in the pieces being fastened together.

Nowadays, modern chemistry has come up with glues and adhesives that can hold as well as nails, eliminating the need to make holes in things. So, can adhesives actually replace nails or is this really a case of different solutions for different problems?

A Quick Primer on Nails

Nails are one of the most common type of metal fasteners used in construction today. They’re available in different shapes (common nails, box nails, casing nails, brads, and finishing nails).
Nails are also available in numerous sizes, measured in a unit known as a Penny (abbreviated with by a lower case letter d). The higher the number, the longer the nail — so a 6-penny (6d) is 2 inches long while a 10-penny nail (10d) is 3 inches.
There are also a wide range of specialized nails. For example some have threading (like drywall or spiral nails) to help them hold more solidly. Others have special coatings of material like zinc or resins to prevent them rusting, and some can be a combination of both (like galvanized spiral nails used for outdoor work).

Nails are widely used because they’re readily available and inexpensive, but there are some issues with nails.

Nails hold much better when they are driven across the grain of a piece of wood rather than along or with the grain, so nails driven into end grain can be pulled out relatively easily.

A nail is actually a form of a wedge. That means when it’s driven into a piece of wood it can actually split the wood in two, particularly if it’s driven too close to the edge or too many nails are driven along the same grain line.
Nails work best when used to hold pieces of wood together. If you need to fasten anything other than wood, nails really aren’t your best choice. They don’t work well with bricks or metal.

What About Adhesives?

Glues have been around probably as long as wooden pegs were used as nails, but, like anything else, natural glues have there downfalls.

They don’t work well in the cold.
Some are water soluble so they won’t last if they’re being used outside where they’re exposed to the elements.
They often take a long time to set up so after gluing pieces together. This means you have to somehow hold the pieces in contact until the glue has dried.
Many of them aren’t really strong enough to hold pieces together when used by themselves, so you will likely need to combine them with nails or brads.

However, modern plastic-based glues and mastics (resin, asphalt, or rubber base) have significant advantages over those natural glues. Contractors and homeowners alike are finding that modern adhesives are invaluable in many construction projects and by using the correct adhesive for the job, you can prevent a lot of maintenance down the road.

Today there aren’t many applications where an adhesive isn’t at least an option to do the job and the choice between glue and nails come down to personal preference.

You can get adhesives that are resistant to rain or snow and some that are even designed to work with frozen or wet wood, so cold and moisture aren’t an issue.

Some new adhesives set up in seconds, so figuring out how to keeping pieces in contact with each other while the glue sets up isn’t a problem.

In fact, in some applications adhesives provide functionality that nails just can’t.

Glues can bond building materials (firring strips) or insulation directly to brick or concrete walls.
You can also put up drywall or paneling with glue, eliminating the need to fill nail holes and ensuring you never need to worry about nail pops.
Mastics can be used to join plywood panels to floor joists, helping eliminate squeaky floors.
There are also some applications where nails just aren’t suitable. For example, jobs like mounting a mirror onto a wall, or installing a bathtub surround are perfect for adhesives.

Choosing the Correct Adhesive

The main challenge is choosing the correct adhesive. Fortunately, most glue manufacturers do a good job of labeling the materials each of their adhesives is designed to work with. So when it comes to choosing an adhesive, take the time to actually read the labels and get the right adhesive for your project.

There’s no doubt modern adhesives can match the holding power of nails, have their own advantages, and in certain applications are the only way of doing the job. However, nails still have the advantage of being inexpensive, easy to use, and readily available. So when it comes down to adhesives or nails, the choice is yours.

Nails or Adhesives