Foundation Repair Mudjacking

Mudjacking, also called slabjacking, for foundation repair is a process that raises a sunken foundation by injecting a slurry of material below a concrete slab.  The slurry is often a mix of cement and soda ash. Urethane foam injection accomplishes the same result.

This process works fine when the foundation drop was caused by soil consolidation due to poor soil compaction.   It is great for regions of the country that only have sandy soil.

Dallas and Fort Worth soils have a high clay content. As clay dries, it shrinks.  When clay becomes hydrated, gets moist, it expands.

The simplicity of mudjacking is that for a relatively low cost, it will raise a foundation above the lowered soil.   Two of the reasons that Dallas Fort Worth foundation fails are interrelated: clay soil consolidation and clay soil drying.

When mudjacking is performed over partially dry clay soil, it will fill the void between clay and slab, and using relatively low pressure, raise the slab.  A problem arises when the underlying clay hydrates and expands.    Since the void between soil and foundation is already filled with the mudjacking slurry material,  the hydrated clay expansion will push the slab upwards, causing it to heave.  So for instance a slab that had dropped 2 inches and been mudjacked to zero, will now rise 2 inches above zero. The soil heave will cause additional house damage.

Granite Foundation Repair never recommends mudjacking on clay soils due to the potential for unintended heave.  It is also why we will not fill the void that arises when piers are used to lift a foundation. What we do recommend is Steel Pier foundation repair.

By using Steel Piers for foundation repair, results will be long lasting and stable.

Every home is different, and another solution may fit the situation better, however steel piers provide the highest quality result.

Contact Granite Foundation Repair today for more information.

Best Foundation Repair Method – Steel versus Concrete

Steel piers are normally the best foundation repair method over concrete piers for the Dallas Fort Worth area.  Our warranty experience is evidence of that fact.

Straight Steel piers are always driven to shale or bedrock at depths of up to 80 feet.   Concrete Piers are typically driven to a maximum depth of 10-20 feet due to the resistance of expansive clay soils.

Why such a difference in pier depth?  3 inch diameter steel piers are far easier to push into the ground than 6 inch diameter concrete.   Steel piers require ¼ the drive force to obtain the same depth as concrete piers.  For a comparison, try pressing a hammer handle and a high heel into your yard.

Both pier systems depend upon the opposing force, the weight of the foundation, to drive the piers.   The available force for most houses is in the range of 4000 to 8000 PSI.    The best that one can hope for in driving pressed concrete is shallow rock, and that all of the soil is pushed out from the base of the pressed concrete using water injection.

These statements are applicable to areas of shallow shale or bedrock. In regions where the hard surface is hundreds of feet thick, concrete piers are preferable to steel and are the only practical choice. For actual field test results, see the following article:  Comparison of Steel Piers and Pressed Concrete Piers for Residential Foundation Repair

Straight steel pier driven deep to load to rock or shale.  Illustration courtesy Granite Foundation Repair

Straight steel pier driven deep to load to rock or shale. Illustration courtesy Granite Foundation Repair

For your free foundation inspection, contact Granite Foundation Repair today. When deciding on the appropriate foundation repair method, it is important to have all the information before making a decision.