I’d like to dig into a construction element known as “mastic” today, and more specifically, the two forms it’s available in. If you’ve never heard of mastic, then you’re in for a little treat because it’s actually pretty neat stuff and has a variety of uses. Before I give too much away, let’s first discuss exactly what it is.

Mastic is an extremely strong adhesive most commonly used in a construction setting. It’s what builders use to seal windows, doors, cracks, but it’s most common usage is hidden beneath your feet. The substance is perfect for setting and bonding tile to concrete or underlayment board due to its properties. Once dried, it is nearly impossible to come off.

Trust me, I’ve had the honor of having to bust out a tiled floor that had been installed in a heavy traffic area for 20 years. Two words: Chisel and hammer. It’s 100% not how you want to spend a Saturday afternoon. Sounds pretty neat though, right? It’s origin is just as interesting. Mastic, coincidentally enough, derives from the resin of the “mastic” tree. Scientifically, this tree is named Pistacia lentiscus, and can be commonly found in the Mediterranean region, specifically Greece and Turkey. Now that you know a little bit more about it, let’s dig into the two forms.

Pre-mixed Mastic


In pre-mixed form, the adhesive tends to be a bit more solid, a little more consistent, making it easier to work with in most instances.

For example, if you’re installing tile for a standup shower, it would be more prudent to use the pre-mixed, so your material isn’t slopping around everywhere, creating waste.

Gravity can be a nuisance when doing projects like tiled showers or backsplashes in your kitchen and bathroom. If you’re not too careful, your workspace can resemble a typhoon rather quickly. And the cleanup is horrendous.

There’s also the convenience factor. When you purchase this kind of mastic, it’s literally ready to go. Take the lid off, grab your trowel, and get to work. It’s as simple as that, BUT like everything else, the convenience of it being pre-mixed comes at a cost.


Depending on where you go, the price comparison is going to be different, but generally speaking, pre-mixed is ALWAYS going to be more expensive. Covering the same amount of square feet, you can typically purchase a bucket of pre-mix for $35 and a bag of powder based mortar for around $16.

It also doesn’t dry as quickly as powder-based mortar, especially if you’re using large tiles. In my experience, we always let shower tiles dry for up to three days before we let the customers use it. Just to be safe. Another thing, if you have to “double float” an area on a wall or the floor because it’s not level, pre-mixed can be a bit of a pain.

Powder-based Mortar


When working with floor tile, powder-based mortar is MUCH easier to work with, especially when working with an uneven floor.

Since you have to mix before applying, you are in complete control over the consistency, allowing you to manipulate if you need a more solid foundation in a certain area, or something a bit “runnier” and easier to work with.

If you’ve ever worked with floor tile then you know exactly how difficult it can be to ensure that every piece is consistently level. No one wants a rocky road in their hallway. I’ve always found the mortar much easier to spread across larger surfaces.

Mastic is a gummy substance, and it can seem like you’re putting much more effort than you need to across a wider surface. With mortar, simply mix it so the consistency isn’t so dry, and it spreads like butter.

Obviously, there are a lot of factors that come into play here like room temperature, how level the surface is, what size or kind of tile you’re using. But for the most part, mortar is the way to go in larger areas. Also, it’s way cheaper than premixed mastic. There’s a reason why, though.


The process of making it can be crazily monotonous, not to mention messy. Plus, there’s the inconvenience of having to keep mixing when you’ve finished your last batch.

Maintaining the same consistency takes a bit of practice, as well. I can’t tell you how many head shakes or sighs of disapproval my father has given me because one batch it perfect in consistency and the next is terribly dry or way too runny. It does take practice, and I’ll go ahead and tell you, if you can’t stand the feeling of dry hands for hours on end, powder-based mortar is not for you. Just throwing that out there.

Using this form of tile adhesive takes some extreme precision, too. Not just in the aspect of consistency, but of neatness, as well. Long story short, things can get horrifyingly messy if you’re not used to it.

My dad and I have a very simple approach when it comes to using these two forms of tile adhesives. Simply stated, we use the premixed when we’re working vertically (shower tiles and backsplashes) and powder-based on horizontal surfaces (floor tile). We’ve done enough tile projects to know gravity can be your worse enemy.

They’re both outstanding products, really. It just depends on the type of work you’re doing and your personal preference. Much like Android vs. iPhone in that regard. Take your pick. Good luck on your tile project!

Builders Surplus is a full service renovation company with locations in Louisville, Kentucky, and Newport, Kentucky, which also serves Cincinnati, Ohio. We are the leading provider of Ledge Stone, wall tile and backsplash tile in Louisville, Newport, and Cincinnati. We specialize in interior design, kitchen design, bathroom remodel, building materials, and home improvement. Interior Design and measurements come as a free service to our clients. We sell building materials ranging in every price point, from unfinished kitchen cabinets to top of the line Wellborn cabinets. In addition to interior design, we also offer installation services. If you have any questions or would like to set up a free design consultation with one of our interior designers, we would encourage you to do so. We love sharing our knowledge with clients & potential home renovators. We write about interior design, home decor, decorating ideas, and home improvement. We hope you’ll check back in for our next article! Happy Renovation!
Written By: Chris Chamberlain