Are Post-Installed Anchors a True 1:1 Replacement for J-Bolts?
At EVstudio, we often get the question: Can we replace cast-in-place J-bolts with post-installed anchors? Most of the time, this question comes up when the foundation is already poured—hard and gray. Recently, a Simpson representative claimed that the Titen HD Washer Head is a 1:1 replacement for J-bolts. We were skeptical, so we put it to the test.
Four post-installed anchors were evaluated against the J-bolt using identical input criteria. The Simpson Strong-Tie Anchor Designer for Concrete software provided a performance comparison. Here’s what the analysis revealed.
Comparing the Anchors
| Anchor Name | Anchor Type | Edge Distance | Steel Strength | Concrete Breakout X- | Concrete Pryout | |
| J- or L Bolt | 1/2″Ø J-Bolt, F593 304/316SS | 2.75″ | 54.2% (3000/5538) | 99.6% (3000/3011) | 41.3% (3000/7268) |  |
| TITEN HD | 1/2″Ø THD, hnom:3.75″ | 2.75″ | 67.1% (3000/4473) | 99.4% (3000/3018) | 57.7% (3000/5198) |  |
| TITEN HD Flat Washer head | 1/2″Ø THDWH, hnom:3.75″ | 2.75″ | 67.1% (3000/4473) | 99.4% (3000/3018) | 57.7% (3000/5198) |  |
| Anchoring Adhesive W/ ½” Threaded rod | SET-3G w/ 1/2″Ø A193 Gr. B6 | 2.75″ | 49.3% (3000/6091) | 99.6% (3000/3011) | 71.7% (3000/4186) |  |
| Strong-Bolt 2 | 1/2″Ø STB2, hnom:3.25″ | 4″ 1 | 63.8% (3000/4703) | 56.8% (3000/5283) | 45.5% (3000/6596) |  |
The following parameters served as a basis for all anchor calculations. Design method: ACI318-19, Load Vuay 3000 lb, Effective Embedment depth (Hef): ~2.75- inch, Concrete: Normal-weight, State: Cracked, Compressive strength: 4000 psi, Seismic design: No.
1. The Simpson Strong-Bolt requires a minimum edge distance (Cmin) of 4-inch.
Key Takeaways
- No True 1:1 Replacement – While the post-installed anchors perform well, it is not a direct substitute in all cases.
- Concrete Breakout is Critical – J-bolts outperform post-installed anchors in pryout resistance.
- Edge Distance Matters – Some anchors require larger edge distances to meet design criteria.
The Importance of Design Phase Planning
Each project is unique, and choosing the right anchor should happen in the design phase, not after construction begins. This allows us to account for spacing and edge conditions to avoid last-minute adjustments.
A Note on Modular Construction
For modular projects, we often use a double sill plate because we cannot countersink anchor bolts. The full height of the sill plate is needed for shear transfer. In these cases, the Simpson Titen HD Washer Head can be a good alternative—if planned ahead of time.
Conclusion
While post-installed anchors provide flexibility, they are not always a 1:1 replacement for J-bolts. In this comparison, concrete breakout is nearly equal across the tested anchors. However, increasing the edge distance shifts the governing factor to either concrete pryout or steel strength, depending on the project conditions. Proper planning and early coordination ensure the best solution for each project. General contractors sometimes have their own preference for post-installed or site-installed anchors for the sill plate. At EVstudio, we are here to help you make the right decisions in the right phase of the project.
[RECOURSES]
Simpson Strong-Tie® Anchor DesignerTM for Concrete software
[BLOGS FOR ADITIONAL INFORMATION]
Fastening to Concrete – Wedge Style Expansion Anchors – EVstudio
