Proper Site Prep for Phoscrete Repairs

concrete repair, phoscrete, site prep

Why Site Prep Matters

A Phoscrete repair is only as strong as the surface it bonds to. Spending a few extra minutes on proper prep means years of reliable, trouble-free performance—saving you time and money on rework.

Step-by-Step Site Prep Best Practices

1. Remove all loose or damaged concrete: Expose solid, sound substrate by removing all unsound material.

2. Eliminate oils, asphalt, and old repair materials.: Use a hard bristle or wire brush for small areas, or a power brush for larger surfaces.

Pro Tip: A propane torch can be used to ā€œkissā€ the surface and burn off stubborn contaminants like oil or asphalt. Keep the flame moving—excessive heat can damage the concrete.

 

3. Ensure the surface is completely dry: Phoscrete bonds best to dry concrete—not SSD. Use compressed air, blowers, or a torch for drying (with care).

 

4. Saw-cut and roughen edges: Avoid feather edges. Saw-cut all boundaries and roughen the surface (ICRI CSP 7–9 for F1, CSP 6 for F3) for optimal mechanical bond.

 

5. Remove all slurry and dust: After wet saw-cutting, thoroughly remove all slurry using a brush, vacuum, or compressed air.

Quick Test: Wipe your gloved finger across the surface—if residue comes off, keep cleaning.

 

6. Prep for reinforcement: Use a wire brush to remove loose rust from exposed rebar. Sandblasting is not required, but all scale should be gone. If using Phoscrete RC, hand-pack a Ā¼ā€ minimum layer onto the steel.

Pro Tip: Check for Carbonation

Don’t let invisible carbonation ruin your bond!
  • How to Test:
Apply a drop of phenolphthalein solution to the prepared concrete surface.
    • Pink = Good: The surface is alkaline and ready for repair.
    • Clear = Carbonated: More prep is needed. keep grinding or chipping until you see pink.

 

  • Why it Matters:
Carbonation lowers the pH at the surface, which can weaken the bond and cause bubbles or delamination. Always check before you build!

Common Mistakes to Avoid

  • Placing Phoscrete on wet, dusty, or contaminated concrete
  • Skipping slurry removal after saw-cutting
  • Leaving feather edges instead of well-defined, saw-cut boundaries
  • Failing to check for carbonation or surface contamination

Need Help or a Custom Checklist?

Contact your Phoscrete Sales Engineer or call our main office at 561 420-0595 for a site prep review, on-site training, or to discuss your next project.
You can also use the live chat on our website or fill out the contact form below.