Instant Epoxy Concrete Crack Repair Compound
Two-part epoxy putty that fills cracks, chips, and divots up to 3/8" wide — then lets you paint or epoxy-coat over it immediately. No 24-hour cure wait. No project delays. Extra-thick formula works on vertical surfaces without sagging.
*1 gallon covers 1,000 linear feet of 1/8" × 1/8" cracks. Less coverage on larger cracks.
Repair Cracks and Coat the Same Day
Most crack repair compounds force you to wait 24–48 hours for full cure before you can apply paint or epoxy over them. That's a full day (or more) of project delay — and if you're coating a garage floor, commercial floor, or production area, that downtime costs money.
ArmorGarage Instant Crack Repair Epoxy eliminates the wait. The two-part putty mixes at a simple 1:1 ratio, trowels into cracks and divots, and lets you apply any ArmorGarage epoxy coating directly over it immediately. No cure wait. No separate trip back to the project. Clean, etch, patch, and coat — all in the same session.
Paint or epoxy coat immediately. This is the fundamental difference that matters. Wait a day with other products, or move straight to your finish coat with this one. For garage floor epoxy projects where timing matters, this product saves an entire project day.
Extra-thick vertical formula. Unlike thin crack fillers that sag and run on vertical surfaces, this compound is extra-thick so it stays put on walls, stair risers, curbs, and overhead surfaces. Fills cracks up to 3/8" wide without the need to add aggregate.
Why This Compound Outperforms Store-Bought Crack Fillers
Kit Sizes & Coverage
Coverage reduces on wider cracks. Figures above are for typical 1/8" × 1/8" hairline cracks. For cracks up to 3/8" wide, plan on significantly less coverage per kit. When in doubt, order the larger size — leftover material stores well.
Color: Gray only. For visible cracks that will be coated over, this is ideal — the epoxy topcoat hides the patch completely.
Application Instructions
- Clean and etch the floor per your epoxy coating prep instructions. Remove all loose concrete, debris, and contaminants from the cracks. The repair area must be clean for proper bond.
- Mix Part A and Part B at a simple 1:1 ratio by volume. Combine only what you can use within the working time — start with small batches until you get a feel for the pace.
- Trowel into cracks and divots using a putty knife or trowel. Press firmly to eliminate air pockets. Smooth flush with the surrounding surface.
- Coat immediately with any ArmorGarage epoxy coating — no cure wait required. This is the main advantage of this product. The epoxy coating will bond to both the wet compound and the surrounding floor simultaneously.
- Alternative: Cure and grind — if you prefer a perfectly flush finish, allow 48 hours cure time and grind down smooth. For most garage floor projects, troweling smooth is sufficient.
Saw cuts and control joints: For control joints and saw cuts (decorative scored lines in the floor), you can leave them unfilled and lightly drag the epoxy coating across them. This creates an attractive "grout line" effect in the finished floor. Most customers prefer this look, but you can fill them with this product or our Crack & Joint Compound if you want a single seamless surface.
Important — expansion joints: If you're filling expansion joints (joints with flexible filler material designed to accommodate slab movement), do NOT use this rigid epoxy compound. Use our Flexible Joint Sealer instead. Filling expansion joints with rigid material will cause the patch to crack as the slabs move.
For Larger or Deeper Cracks
Instant Crack Repair is ideal for cracks up to 3/8" wide. For repairs beyond that range, ArmorGarage offers purpose-built products:
- Crack & Joint Compound — applied like grout for wider cracks, larger holes, and pitted areas. Cures to a smooth paintable finish.
- Vertical Concrete Crack Repair Patch — 7,800 PSI no-sag formula for concrete walls, block, brick, and vertical surfaces.
- All Concrete & Asphalt Repair Products — full repair product lineup for any job.
Frequently Asked Questions
Can I really paint or epoxy coat over this immediately?
Yes — this is the main advantage of this product. Apply any ArmorGarage epoxy coating directly over the wet patch. No 24-hour cure wait. The coating bonds to both the fresh compound and the surrounding floor. Most other crack repair products require full cure before coating, which adds a day to your project timeline.
What's the largest crack this can fill?
Up to 3/8" wide without adding aggregate — the extra-thick formula holds its shape even at that width. For cracks wider than 3/8", use our Crack & Joint Compound which is designed to be applied grout-style for larger voids.
Will it work on vertical surfaces like walls and stair risers?
Yes — the extra-thick formula is specifically engineered to stay put on vertical surfaces. It won't sag or run. For larger wall repairs or structural wall crack work, see our Vertical Concrete Crack Repair Patch which is designed for deeper vertical voids with 7,800 PSI compressive strength.
What's the mix ratio?
Simple 1:1 ratio by volume — equal parts A and B. Mix only what you can use within the working time. Start with smaller batches until you get comfortable with the pace.
Can I use this in expansion joints?
No. Expansion joints are designed to accommodate slab movement — filling them with rigid epoxy will cause the patch to crack as the slabs move. Use our Flexible Joint Sealer for expansion joints. Control joints and saw cuts are different and can be filled with this product if desired, though many customers prefer to leave them open as decorative grout lines.
How does this compare to store-bought concrete patch?
Store-bought patches are typically cement-based fillers that cure at or below the strength of the original concrete. They fail again as the concrete continues to move. ArmorGarage Instant Crack Repair is a two-part epoxy that chemically bonds to the substrate and cures rock-hard, stronger than the surrounding concrete. It's a fundamentally different product category designed for permanent repair rather than temporary filling.
Do I need to grind the patch down before coating?
Not required for most projects. If you trowel the patch smooth with the surrounding surface, you can coat directly over it. If you want a perfectly flush finish with zero texture difference, allow 48 hours cure and grind down smooth before coating. For a typical garage floor project, troweling smooth is sufficient.
Related: All Repair Products | Garage Epoxy Kits | Industrial Epoxy | Commercial Epoxy
Repair and Coat the Same Day
Questions about your specific repair or which compound fits the job? We'll help you get it right the first time.
Mix Part A & Part B according to label instructions on piece of wood or cardboard till the product becomes a putty like consistency. You don't have to mix all the product at once, just maintain the proper mix ratio. Then simply trowel or putty knife into cracks and divots. Scrape level and remove any excess material. For cracks deeper than 1/2" use foam backer rod to fill crack to within 3/8" of the top of slab. Once repairs are done you can immediately apply any of our epoxy primers or epoxy floor coatings over it. No need to wait for it to cure. You can let it harden for 48 hrs and grind down smooth if need be. This is a very versatile repair product and super durable. Will not crack or chip out like Home Improvement Store products.
For large repairs see our Crack & Joint Compound.
