Should You Install the Shower Floor Tile First?

When it comes to shower installations, there’s no strict rule that dictates whether you must tile the floor or the walls first. However, when we apply practical logic and real-world experience, it’s clear that modern materials—while offering many advantages—also come with limitations compared to traditional methods.

Traditional shower pans, built with a properly installed PVC liner and topped with a thick layer of mortar, are incredibly durable. The final cement layer is strong enough to withstand impacts from hammers, knives, dropped tiles, and other heavy objects without compromising the waterproof liner. This is because the liner is safely embedded deep beneath the concrete, allowing installers to walk freely without fear of damage.

Modern systems, however, often involve lightweight foam shower bases. These systems are much easier and faster to install, but they do not match the strength and impact resistance of a mortar bed over a PVC liner. A dropped hammer or tile on a foam pan might leave a dent or mark. While minor damage can usually be patched, it reveals the natural vulnerability of the material.

Then we have advanced waterproofing membranes like Schluter’s Kerdi system.

These membranes are incredibly versatile, allowing installers to blend traditional methods with modern technology. However, they must be handled with extreme care. A tear in a Kerdi membrane — during or after installation — could lead to major water damage because the membrane serves as the primary waterproof barrier and sits directly beneath the tile layer.

Unlike a traditional PVC system, where the liner is buried under few inches of concrete, Kerdi is exposed right beneath the tile, making repairs much riskier.

Consider the differences:

• Repairing a chipped tile in a traditional PVC liner shower pan is relatively safe, because the waterproofing remains deeply protected.

• Removing a chipped tile from a foam pan can be tricky, since foam is soft and can easily be damaged by tools and chisel vibration. 

Repairing a chipped tile over a Kerdi membrane is the riskiest — even a small mistake can puncture  or detach the membrane (waterproofing) compromising the entire shower system.

After more than 35 years of professional experience without a single failure in any of my shower installations, I can confidently say: installing the shower floor tile first is the smartest choice when working with modern systems or hybrid methods.

Once the floor is tiled, it should be properly protected by covering it with a 1/8” plywood sheet or similar material. This prevents accidental damage during wall tile installation and greatly reduces the risk of needing difficult repairs later on.

Kerdi Shower Pan

Tile Installed over Kerdi Shower Pan

Shower TIle Protection in Place

Tile Installation Has Been Completed

Completed Shower Project

Final Note

This article and analysis were written by Salvador Cornejo, a second-generation tile contractor with over 35 years of hands-on experience in the trade.

Throughout my career, I am proud to say with complete honesty and gratitude to God — that I have never experienced a single shower failure.

Every project I complete reflects the knowledge, care, and craftsmanship passed down through generations.

Authored by: Salvador Cornejo

Company: Houston Tile Works