What are the requirements for retaining walls?

Retaining wall requirements are covered under Section R404.4 of the 2015 International Residential Code and 1807.2 of the 2015 International Building Code.

  • Retaining walls less than forty-eight (48) inches in height measured from the bottom of the footing to the top of the wall that are not supporting a surcharge do not require a permit.
  • Retaining walls over forty-eight (48) inches in height measured from the bottom of the footing to the top of the wall require a permit and must be designed by a registered design professional.
  • Retaining walls up to forty-eight (48) inches in height are not required to be designed by a registered design professional as the most common manufacturers and products used in retaining walls (pave stone for example) have designs and charts available in their technical resources online. If the applicant shows a design using unusual materials that are outside of code (railroad ties or bags of concrete spiked in place, for example), then an engineer-sealed structural letter would be required at time of final inspection.

Show All Answers

1. As a homeowner doing my own work at my home, when am I required to obtain a permit?
2. Why should my contractor obtain the permit instead of me, as the homeowner?
3. How can I find out which contractors are registered with the Town?
4. How long will it take to get my permit application reviewed?
5. How long is my permit valid for after being issued?
6. My Homeowner’s Association (HOA) is telling me that I cannot build my project. Is this true?
7. Are subcontractors required to pull separate permits for larger projects?
8. Do I need a permit to build a deck?
9. Is a permit required to build a patio cover/shade arbor?
10. Is a permit required for an accessory building (storage shed)?
11. Do I need a Certificate of Occupancy for my business?
12. Can I move furniture and/or equipment into a commercial space prior to receiving my Certificate of Occupancy?
13. When is a fence permit required?
14. What are the requirements for retaining walls?
15. Is a permit required for foundation work?
16. If my sidewalk (flatwork) has already been approved, can I replace a section without a permit?
17. Do scheduled inspections automatically rollover after being canceled due to weather?
18. Can I install my own irrigation system on my property?
19. When is a permit required for heating or air conditioning work?
20. Can I add flatwork that isn’t shown on the approved construction plans for my house?
21. Does the Town issue Temporary Certificate of Occupancies on new homes?
22. Do I need a permit to install a flagpole in my yard?
23. What type of temporary signage is allowed for business grand openings in the Town of Prosper?
24. Is a permit required for Banner Signs and/or Inflatable Signs?
25. How early do I need to submit for a sign permit?
26. Are wind devices, such as pennant flags, streamers, spinners, balloons, feather signs, or similar devices allowed within the Town of Prosper?
27. What is a Special Event?
28. Is a permit required for a Special Event?
29. How early does a Special Event permit need to be submitted?
30. Do I need a permit to install a self-contained spa?
31. Is it true that replacing a water heater in my house requires a permit?
32. The plumber tells me that my water heater now requires a drain pan. Is this true?
33. Does the building code allow plumbers to install a water heater in an attic?