User Notes and Calculator Assumptions

1. This calculator is based on the provisions of TMS 402/602-16 and TMS 402/602-22, Building Code Requirements and Specification for Masonry Structures. As there is no functional difference between the requirements of these two editions of the masonry design standard pertaining to the determination of minimum lap and development lengths, either edition is applicable.
2. Chapter 21 of the International Building Code includes modifications to TMS 402/602 when determining minimum lap splice lengths and caps the maximum required lap splice length at 72db. These modifications are captured with this calculator and shown separately.
3. TMS 402 does not have different design provisions for determining lap and development lengths. Except when applying the confinement adjustment when transverse reinforcement is present, which is applicable only to lap splices, the resulting lap and development lengths are interchangeable. Similarly, lap and development lengths are calculated the same whether using the allowable stress design or strength design provisions of TMS 402.
4. This calculator is applicable to deformed bars and wire only.
5. Highlighted cells are user inputs. All inputs and outputs use inch-pound units.
6. When using transverse reinforcement to confine lap splices, the calculated lap splice length may increase over the minimum lap length when confinement is not present or not accounted for. This is because TMS 402 stipulates a minimum baseline lap length of 12 in. without confinement and a minimum lap length of 36db when confinement is considered.
7. The calculator offers two options to determine the required lap or development length. The first tab provides tabulated results for all bar diameters assuming the reinforcement is centered in the masonry wall. The second option allows users to input specific K (cover or clear distance) values and returns individual results.