While property owners often confuse the two, a Perc Test and a Geotechnical Report serve entirely different purposes and cannot be used interchangeably for structural work.
### Perc Test (Percolation Test)
- Primary Purpose: Used solely for septic system design.
- Key Data: It measures the soil’s absorption rate in minutes per inch to determine the size of a leach field.
- Structural Relevance: It provides no data on whether soil can support a building. Building departments will not accept a perc test for foundation permits.
- Typical Cost: $100 – $300 per test hole.
### Geotechnical Report
- Primary Purpose: Evaluates soil bearing capacity for structural foundation design and repair.
- Key Data: Provides comprehensive technical details including soil type classification, density, groundwater depth, shear strength, and shrink/swell potential.
- Structural Relevance: Essential for calculating foundation dimensions and determining the depth and spacing of helical piers.
- Typical Cost: $800 – $3,500 depending on the project scope and site access.
In the Denver metro area, geotechnical reports must be prepared by a licensed geotechnical engineer and follow ASTM standards to ensure the long-term stability of the structure.
Related FAQs
-
Are Diagonal Cracks above Doors Normal in a New Build?
Read More »: Are Diagonal Cracks above Doors Normal in a New Build?Diagonal drywall cracks above door frames are a common occurrence in new construction, and in many cases, they are a normal part of the home’s adjustment process. As a new home settles, the underlying soil compacts under the weight of…
-
Is a Vertical Crack above a Door Frame Structural or Cosmetic?
Read More »: Is a Vertical Crack above a Door Frame Structural or Cosmetic?Whether a crack above a door frame is structural or cosmetic depends primarily on its width, pattern, and associated symptoms. While many diagonal cracks in new construction result from normal settling or lumber shrinkage, certain indicators signal a need for…
-
Why is the Drywall Cracking in the Corners of my New House?
Read More »: Why is the Drywall Cracking in the Corners of my New House?Diagonal drywall cracks radiating from the upper corners of door frames are a common occurrence in new construction, typically resulting from differential foundation settlement. This process occurs as your house adjusts to the underlying soil conditions. In Centennial and throughout…
-
Which is Better for Fixing Uneven Concrete Slabs: Foam or Piers?
Read More »: Which is Better for Fixing Uneven Concrete Slabs: Foam or Piers?When determining the best method for fixing uneven concrete, the choice between polyurethane foam and steel piers depends largely on the weight of the structure and the condition of the soil. For settled concrete slabs such as driveways, patios, or…
-
What are the Pros and Cons of Polyurethane Foam Vs. Steel Piering?
Read More »: What are the Pros and Cons of Polyurethane Foam Vs. Steel Piering?When choosing between polyurethane foam vs steel piers foundation repair for your property in Centennial, the best approach depends on whether you are lifting a simple concrete slab or stabilizing a structural foundation wall. Each method offers distinct advantages and…
