When it comes to industrial equipment, proper grouting is essential for stability, longevity, and performance. Whether you’re re-grouting a pump or securing heavy machinery, following the correct process ensures a solid foundation and prevents premature failure. If you don’t grout equipment regularly, use this guide to refresh your knowledge and avoid costly mistakes. While this equipment grouting guide applies to most grouts, we’ll be using Five Star Grout and Five Star DP Epoxy Grout as examples.
1. Selecting the Right Grout for Your Application
Selecting the correct grout is the foundation of a successful installation. The type of grout you need — cementitious or epoxy — depends on factors like vibration levels, load-bearing requirements, and exposure to chemicals. Review manufacturer application guides or consult an expert to ensure the best fit for your specific conditions. If you’re unsure, Indcon’s team can walk you through the selection process.
Choosing the correct grout depends on the application’s requirements:
- Cementitious grout (Five Star Grout) is ideal for static loads, structural steel applications, and precast concrete. It offers high strength, non-shrink performance, and ease of use.
- Epoxy grout (Five Star DP Epoxy Grout) is preferred for high-impact loads, dynamic machinery, and aggressive chemical environments. It provides high creep resistance, chemical resistance, and strong adhesion to steel.
2. Surface Preparation: Ensuring a Strong Bond
A strong bond between the grout and the baseplate starts with proper surface preparation. This may involve roughening the surface using bushing, chipping, or sandblasting. Proper surface preparation is essential for achieving maximum adhesion and long-term durability. Skipping this step can lead to adhesion failure, reducing the effectiveness of the grout.
For Cementitious Grouts (Five Star Grout):
- Remove contaminants (oil, grease, dust) from concrete and steel surfaces.
- Roughen concrete to expose coarse aggregate (ICRI CSP 6-9 recommended).
- Pre-soak concrete with water for 8-24 hours before grouting, but remove standing water.
For Epoxy Grouts (Five Star DP Epoxy Grout):
- Ensure surfaces are dry — epoxy does not bond well to moisture.
- Remove contaminants and roughen concrete for better adhesion.
- Steel surfaces should be prepared to an SSPC-SP6 commercial finish to optimize bonding.
3. Formwork: Containment for Proper Placement
Well-sealed forms are essential to contain the grout and maintain the correct pour shape. A good rule of thumb is that if your forms can hold water, they will hold grout. Use materials that can withstand the weight and pressure of the grout while preventing leaks or blowouts during placement.
- Use rigid, liquid-tight, and non-absorbent formwork materials.
- Secure forms tightly to prevent grout leaks or displacement.
- Leave 1-2 inches of clearance around baseplates for flow.
- Apply form release agents on areas where bond is not desired.
4. Mixing: Achieving the Right Consistency
Grout consistency plays a crucial role in performance, and using the correct mixing method ensures the material reaches optimal strength. Cementitious grouts require aggressive, high-energy mixing to activate the cement and achieve proper flow. Epoxy grouts should be mixed at low speeds to avoid air entrapment and excessive heat buildup, which can compromise strength and working time.
For Cementitious Grouts (Five Star Grout):
- Use a mortar mixer for best results. A drill and paddle mixer can be used for small batches.
- Mix for 4-5 minutes until smooth and lump-free.
- Water content: 7-11 quarts per 100 lb. bag (DO NOT exceed recommended water limits).
For Epoxy Grouts (Five Star DP Epoxy Grout):
- Pre-condition all components to 70-80°F for optimal performance.
- First, mix Component A (resin) and Component B (hardener) until fully blended.
- Add Component C (aggregate) slowly while mixing in a mortar mixer.
- Use 4 bags of aggregate for high flow applications and 5 bags for standard flow.
- Avoid excessive mixing time to prevent air entrapment.
5. Placement: Pouring or Packing for Full Support
Grout should be placed immediately after mixing to prevent premature setting.
For Cementitious Grouts (Five Star Grout):
- Use a continuous pour from one side to push air out and avoid voids.
- Minimum thickness: 1 inch (25 mm).
- For pours over 6 inches (150 mm), extend with clean, damp coarse aggregate (ASTM C 33 compliant).
- Can be dry packed, poured, or pumped, depending on the application.
For Epoxy Grouts (Five Star DP Epoxy Grout):
- Pour from one side to the other to ensure continuous contact with the baseplate.
- Use a headbox for better flow and air displacement.
- Minimum thickness: ½ inch (13 mm); Maximum thickness: 18 inches (457 mm).
- Epoxy grout is self-leveling, but a plunger can help guide flow.
6. Curing: Protecting the Grout for Maximum Strength
Curing is a critical step in equipment grouting that should never be rushed. Allow for the appropriate cure time before starting up your equipment to avoid early failures. Cementitious grouts require wet curing and an appropriate curing compound to retain moisture and prevent cracking. Epoxy grouts must be protected from water and direct sunlight during the curing process to prevent soft spots or improper chemical reactions. Proper curing is crucial to achieving full strength and long-term performance.
For Cementitious Grouts (Five Star Grout):
- Wet cure for at least 3 days using damp burlap or plastic sheets.
- After 24 hours, apply a curing compound that meets ASTM C 309 requirements.
- Protect from direct sunlight, extreme temperatures, and early loading.
For Epoxy Grouts (Five Star DP Epoxy Grout):
- Epoxy grout does not require wet curing.
- Keep surfaces clean and avoid water exposure until fully cured.
- Allow 24-48 hours before subjecting to heavy loads (cure time depends on temperature).
7. Post-Placement and Cleanup
- Check alignment of equipment and ensure full grout coverage under baseplates.
- For cementitious grouts, trim excess material before it fully hardens.
- For epoxy grouts, use a solvent-wiped trowel to smooth exposed edges.
- Clean tools immediately — cementitious grout can be washed with water, while epoxy grout requires a solvent before it hardens.
8. Additional Considerations
- Temperature Matters:
- Cementitious grout should not be exposed to freezing temperatures until it reaches 1,000 psi strength.
- Epoxy grout should be used in temperatures between 55°F and 90°F for best results.
- Yield Adjustments:
- For large placements, cementitious grout may need extension with aggregate
- Epoxy grout should be measured carefully to ensure proper coverage.
- Long-Term Performance:
- Both grout types must reach full compressive strength before machinery is put into service.
- Regularly inspect grouted areas for signs of cracking or wear.
Final Checklist for a Successful Grouting Installation
- Concrete roughened and properly prepped
- Forms sealed and secured
- Correct grout type selected for the application
- Mixed according to manufacturer’s guidelines
- Proper placement method used to eliminate voids
- Curing process followed
- Cleanup completed before materials harden
Following this guide to equipment grouting ensures a durable, high-strength bond for your equipment and structures. If you need assistance selecting the right grout or troubleshooting an installation, Indcon provides expert guidance and high-quality grouting materials for industrial applications.
Whatever your equipment grouting needs, we’re here to help. Give us a call for expert advice on product selection and application. Check out our line sheet to see the wide range of products we offer.
Now that you’ve got a rough guide for your pour, take an inventory of what tools and equipment you’ll need to get it done. Do so with our “Cement Grouting Checklist” and our “Epoxy Grouting Checklist” below.
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