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03 June 2013

How to Choose a Grout for Sealing Mainlines and Laterals

Posted in Water & Wastewater


Below are some questions to consider when choosing a grout for sealing mainlines and laterals--before, after, or independent of lining:

  1. Cost: Cost should only be one factor. What is more important is that you are using the appropriate product for the job and the grout is applied correctly (in accordance with the 2012 NASSCO recommendation is a good start - click here to download).
  2. Cost vs. Cure Time: Grouts have different cure times. Be sure to check tech data sheets to determine how much control over cure time you will have in the field. Better yet, you can do a more thorough investigation by performing your own tests. The more catalyst you need to reach the desired goal, the more money you'll spend on product.
  3. Viscosity: The thinner the grout, the better it will permeate the soil outside the pipe. Remember, the joints are sealed by creating a gel/soil matrix outside the pipe. You want the grout to permeate.
  4. Longevity: How long will the grout last? Be sure to look up case studies and third party testing.
  5. Packaging: Some contractors prefer to keep liquid product on hand (drums), while others prefer to use granular materials (bags) in order to save on shipping costs and space in the truck.
  6. Training and Support: Be sure that you have a mentor or team of people who can teach as well as answer questions for you "after the sale has been made" and when you are facing challenges out in the field.
  7. Safety: Safety is important ANY time you are working with chemicals. When it comes to personal protective equipment (PPE), know what you should wear and when you should wear it. Grouting mainlines and laterals is done via remote control so the only time you need to wear chemical PPE is when you are mixing or physically handling the chemical elements, which only takes a few minutes. We sell acrylamide, acrylic, and acrylate grouts. All three require an oxidizer (hazardous), the same catalyst, and the same PPE. Some chemical grout suppliers will tell you that their grout is safe because you don't need PPE...that is not true. Any time you are working with a chemical that could splash onto your body or clothes, you should wear PPE. Read the MSDS which should be readily available for download.
  8. Easy Clean-Up: What additional chemicals does it take to clean your hoses/packers, etc., if any? Do you have to pump acetone through the pump beforehand to remove moisture from the hoses?
  9. Pump/Pump Ratio: Are you set up to pump 1:1 or 8:1? The type of pump you have may impact which grout product you'll use.

If you have any questions on any or all of the above grout attributes, let us know and we'll be glad to get you the info you need. After all, that's what we do!