FAQ: Fiberglass Rebar in Masonry Walls
We’ve set up this simple FAQ to address some common questions about GFRP (fiberglass rebar)
Why Fiberglass Instead of Steel?
Simply it’s cheaper. As of March 3, 2023 Ernest Maier is selling 6’8″ #4 bars at a 32% discount over black steel.
Furthermore, because it’s lighter labor can place faster and deliveries can carry more (or other job materials).
- Fiberglass rebar has 2x-3x the tensile strength of steel rebar
- No corrosion
- Lighter (one-quarter the weight)
- Bonds better to concrete
Do the Codes Allow It?
Yes, Appendix D of the 2022 edition of TMS 402/602 allows for this. While the current building codes may reference earlier editions of the TMS 402/602 code, you can request a substitution with the relevant authority.
What do I need to do substitute?
Speak with your engineer/GC and provide this letter of substitution: L-CMU REINFORCEMENT 2023
What About Bent Bars?
While fiberglass rebar cannot be field bent, we stock elbows and common bends. More importantly the bend is unnecessary. The starting bar has been typically bent to get development length without touching the ground, where it would corrode. GFRP doesn’t corrode, so there is no minimum cover needed to resist corrosion. Because the bar doesn’t corrode you can just go vertical. Additionally it has a higher bond strength to concrete.
Handling or Restrictions?
- Cutting should be done with a diamond saw blade- other precautions as usual: eye-protection, well-ventilated space
- Wear gloves
- Since its lighter, it is usually easier to manipulate and handle on site. This includes putting bundles on your standard pickup truck.
- 6-month of UV exposure will cause the bar to degrade– but no concern from moisture.
- Everything else is the same as with normal steel
Are there limitations?
GFRP can only substitute for #3, #4, #5, or #6 reinforcement in a masonry wall.
TMS 402/602 does limit the application of GFRP to non-bearing walls, infill, retaining walls and lintels, up to 200 plf. In plain English, this means stairwells and elevator shafts are great applications. That being said ACI codes and numerous state DOTs, allows GFRP everywhere…
Speak with an Ernest Maier masonry representative to answer your questions.
Ernest Maier and Gomoljak Counter Price Sheet
Pricing accurate as of 3/1/2023 and valid for Annapolis, Bladensburg, and Gaithersburg locations (contact us for bulk pricing and delivery): […]
Trees Will Not Save Us From Climate Change
There is this magical view that forests and trees are going to save us from climate change. They will certainly […]
Optimizing Environmental Impact in Structural Design
As a sustainability focused construction professional I frequently hear folks think of sustainability as something you do as the last […]
Concrete: Sustainability and Resilience
The content of this post is available as a PDH. Concrete has been painted as a material bad for the […]
Better for the Bay: A PaveDrain Case Study
Ernest Maier and PaveDrain are proud to announce the release of our latest case study highlighting the performance of an […]