21 N.C. Admin. Code 28B.0508

Current through Register Vol. 39, No. 8, October 15, 2024

Section 28B .0508 - WALLS

(a) When installing retaining walls, the licensed contractor shall:

(1) Adhere to all pertinent codes;

(2) Adhere to all NC Department of Insurance requirements regarding the construction of retaining walls which are hereby incorporated by reference and can be found at www.ncosfm.gov/codes free of charge;

(3) Adhere to manufacturer's or design professionals specifications;

(4) Bury the first course of a retaining wall;

(5) Not construct dry-laid stone walls of a height more than 3 feet above grade;

(6) Include a subdrain system that is constructed and sized to release the subsurface water behind the wall and not allow hydrostatic pressure to build behind the wall;

(7) Construct on a level, well-compacted base of granular material at least 6 inches deep;

(8) Place backfill behind retaining walls in lifts no greater than 6 inches before compacted (each lift shall be well-compacted);

(9) Prevent excessive runoff from passing over a retaining wall;

(10) Construct vertically-set timber walls with above-ground heights equal to or less than the depth of timbers below grade;

(11) Install deadmen every fourth course on 8 feet centers when constructing horizontally-set timber retaining walls with staggered joints;

(12) Stagger the joints when constructing dry-laid stone walls. If successive vertical joints occur, the licensed contractor shall avoid running vertical joints more than two courses; and

(13) Assure that segmental walls meet the manufacturer's specifications.

(b) When installing retaining walls of dry-laid stone or concrete rubble, the licensed contractor shall:

(1) Construct the wall no higher than 3 feet above grade; and

(2) Stagger the joints when constructing a dry-laid stone wall.

(c) When installing freestanding walls, the licensed contractor shall:

(1) Install footings for masonry and cast-in-place concrete freestanding walls of reinforced concrete. The top of the footing shall be at least 1 foot below grade.

(2) Reinforce freestanding walls as needed to prevent displacement from wind loads.

(3) Ensure that moisture is prevented from entering a cavity wall during construction.

(4) Ensure that segmental wall construction meets segmental wall manufacturer's specifications.

21 N.C. Admin. Code 28B .0508

Authority G.S. 89D-15(2); 89D-15(16);
Temporary Adoption Eff. January 1, 2016;
Eff. September 1, 2016;
Amended Eff. July 1, 2021.

Authority G.S. 89D-15(2); 89D-15(16);
Temporary Adoption Eff. January 1, 2016;
Adopted by North Carolina Register Volume 31, Issue 07, October 3, 2016 effective 9/1/2016.

Amended by North Carolina Register Volume 36, Issue 03, August 2, 2021 effective 7/1/2021.