Urethane Cement Flooring Joint Prep (ProKrete SL Method)
Cementitious Urethane Food & Beverage
Manufacturing Pharmaceutical Georgia North Carolina South Carolina
Urethane Cement Flooring Joint Prep: How We Treat Joints Under the System
Urethane cement flooring performs best when the substrate is prepared correctly—especially in food production facilities and commercial kitchens. Here’s how we treat applicable joints and static cracks before installing a cementitious urethane system like ProKrete SL.
At Liquid Floors, we handle these areas the right way: we clean joints out, pre-fill with cementitious urethane before the system goes down, then grind everything flush. That creates a flatter, more uniform substrate for a premium ProKrete SL install.
Important note about movement joints: This article covers non-working (non-moving) joints and static cracks treated as part of the substrate under the system. Expansion joints and other true movement joints must be honored and detailed through the finished flooring system—they are not buried under a monolithic topping.
Learn more about our cementitious urethane systems:
Why Joint Prep Matters for Urethane Cement Flooring
Contractors choose cementitious urethane for tough spaces because it handles moisture, thermal swings, chemicals, and impact. But if the substrate has dirty, ragged, or uneven joint areas, those weak spots can show up fast.
Poor joint prep often leads to:
- joint telegraphing (lines showing through the finished floor)
- ridges or low spots that affect thickness and appearance
- edge breakdown at stressed transitions
- avoidable maintenance and callbacks
In short, urethane cement flooring looks better and lasts longer when joints and static cracks are addressed before installation. A self-leveling urethane cement system like ProKrete SL performs best when the base is clean, consistent, and flat.
The Wrong Way (What Causes Problems Later)
Common shortcuts we see:
- coating over joints without cleaning them out
- trying to patch problem joints after the system is installed
- using an incompatible filler that doesn’t behave like urethane cement
- skipping grind-back, leaving proud joints that print through
Even if the floor looks okay on day one, those shortcuts often show up later as visible lines, uneven wear, or deterioration of joint edges.
Urethane Cement Flooring Joint Prep (Non-Moving Joints Only)
1) Open and clean out the joint/crack area
We start by mechanically opening and cleaning the area so the repair bonds to sound concrete—not dust, residue, or weak edges. Depending on joint condition and project requirements, this may involve professional cutting equipment such as a Hilti concrete saw.
Goal: clean walls, sound edges, and a profile that supports proper bonding.
2) Pre-fill applicable joints with urethane cement before the system goes down
For non-working joints and static cracks treated as part of a monolithic substrate, we pre-fill with cementitious urethane prior to installing the rest of the system.
Why this matters:
- creates a more uniform base
- helps reduce telegraphing through the finished floor
- improves consistency under self-leveling toppings
We handle movement joints differently: we honor expansion joints and detail them after installation to allow for slab movement.
3) Grind the filled areas flush and smooth
After the filler cures, we grind it back flush with the surrounding slab. This is the step that prevents ridges and keeps the final system looking uniform.
We typically use professional grinding equipment, such as a SASE grinder, for consistent results and a clean surface profile.
4) Install ProKrete SL over a flat, consistent substrate
Once the surface is uniform, we install ProKrete SL, a self-leveling urethane cement system commonly installed around 3/16″ to 1/4″, depending on the environment and performance needs.
This workflow supports a floor that is:
- more uniform and monolithic in appearance
- less prone to joint telegraphing
- better prepared for demanding service conditions
Why This Sequence Works (Clean → Pre-Fill → Grind → Install)
Instead of trying to “hide” joint issues under a finished topping, we first correct the substrate. The result is a smoother install and a system that performs the way it’s designed to—especially in food production and commercial kitchen environments where floors take constant abuse. For long-term performance, urethane cement flooring depends on proper prep—especially at joints and transitions.
See More Urethane Cement Flooring Projects
Serving NC, SC, GA, and nationwide.
Request a Quote
Urethane Cement Flooring Joint Prep FAQ
Is this process for expansion joints?
No. This article focuses on non-moving joints and static cracks being treated under the system. Expansion/movement joints must be honored through the flooring system.
Can joint lines show through cementitious urethane flooring?
Yes—if joints aren’t cleaned, pre-filled (where appropriate), and ground flush, they can telegraph through the finished surface.
What is ProKrete SL?
ProKrete SL is a self-leveling cementitious urethane system designed to create a smooth, monolithic floor surface for industrial and commercial environments.
Urethane Cement Flooring Joint Prep: How We Treat Joints Under the System
Urethane cement flooring performs best when the substrate is prepared correctly—especially in food production facilities and commercial kitchens. Here’s how we treat applicable joints and static cracks before installing a cementitious urethane system like ProKrete SL.
At Liquid Floors, we handle these areas the right way: we clean joints out, pre-fill with cementitious urethane before the system goes down, then grind everything flush. That creates a flatter, more uniform substrate for a premium ProKrete SL install.
Important note about movement joints: This article covers non-working (non-moving) joints and static cracks treated as part of the substrate under the system. Expansion joints and other true movement joints must be honored and detailed through the finished flooring system—they are not buried under a monolithic topping.
Learn more about our cementitious urethane systems:
Why Joint Prep Matters for Urethane Cement Flooring
Contractors choose cementitious urethane for tough spaces because it handles moisture, thermal swings, chemicals, and impact. But if the substrate has dirty, ragged, or uneven joint areas, those weak spots can show up fast.
Poor joint prep often leads to:
- joint telegraphing (lines showing through the finished floor)
- ridges or low spots that affect thickness and appearance
- edge breakdown at stressed transitions
- avoidable maintenance and callbacks
In short, urethane cement flooring looks better and lasts longer when joints and static cracks are addressed before installation. A self-leveling urethane cement system like ProKrete SL performs best when the base is clean, consistent, and flat.
The Wrong Way (What Causes Problems Later)
Common shortcuts we see:
- coating over joints without cleaning them out
- trying to patch problem joints after the system is installed
- using an incompatible filler that doesn’t behave like urethane cement
- skipping grind-back, leaving proud joints that print through
Even if the floor looks okay on day one, those shortcuts often show up later as visible lines, uneven wear, or deterioration of joint edges.
Urethane Cement Flooring Joint Prep (Non-Moving Joints Only)
1) Open and clean out the joint/crack area
We start by mechanically opening and cleaning the area so the repair bonds to sound concrete—not dust, residue, or weak edges. Depending on joint condition and project requirements, this may involve professional cutting equipment such as a Hilti concrete saw.
Goal: clean walls, sound edges, and a profile that supports proper bonding.
2) Pre-fill applicable joints with urethane cement before the system goes down
For non-working joints and static cracks treated as part of a monolithic substrate, we pre-fill with cementitious urethane prior to installing the rest of the system.
Why this matters:
- creates a more uniform base
- helps reduce telegraphing through the finished floor
- improves consistency under self-leveling toppings
We handle movement joints differently: we honor expansion joints and detail them after installation to allow for slab movement.
3) Grind the filled areas flush and smooth
After the filler cures, we grind it back flush with the surrounding slab. This is the step that prevents ridges and keeps the final system looking uniform.
We typically use professional grinding equipment, such as a SASE grinder, for consistent results and a clean surface profile.
4) Install ProKrete SL over a flat, consistent substrate
Once the surface is uniform, we install ProKrete SL, a self-leveling urethane cement system commonly installed around 3/16″ to 1/4″, depending on the environment and performance needs.
This workflow supports a floor that is:
- more uniform and monolithic in appearance
- less prone to joint telegraphing
- better prepared for demanding service conditions
Why This Sequence Works (Clean → Pre-Fill → Grind → Install)
Instead of trying to “hide” joint issues under a finished topping, we first correct the substrate. The result is a smoother install and a system that performs the way it’s designed to—especially in food production and commercial kitchen environments where floors take constant abuse. For long-term performance, urethane cement flooring depends on proper prep—especially at joints and transitions.
See More Urethane Cement Flooring Projects
Serving NC, SC, GA, and nationwide.
Request a Quote
Urethane Cement Flooring Joint Prep FAQ
Is this process for expansion joints?
No. This article focuses on non-moving joints and static cracks being treated under the system. Expansion/movement joints must be honored through the flooring system.
Can joint lines show through cementitious urethane flooring?
Yes—if joints aren’t cleaned, pre-filled (where appropriate), and ground flush, they can telegraph through the finished surface.
What is ProKrete SL?
ProKrete SL is a self-leveling cementitious urethane system designed to create a smooth, monolithic floor surface for industrial and commercial environments.
