There are generally two types of chemical grouting:

• Permeation Grouts
  Form a stone-like material similar to sandstone by injecting a polyurethane based grout into granular soil under pressure. The chemical grout material permeates the soil and solidifies to increase the strength of the strata and it's load bearing characteristics. This method us especially effective in shallow soils.
• Chemical Grouting
  The second type is the injection of an expansive foam that fills voids and can be used to lift and relevel slabs and sometimes foundations.