What is the coverage rate for Carboguard 501?

Coverage is depth-dependent: approximately 12.8 SF per gallon at 1/8 inch fill (about 46 SF per 3.6-gallon kit). Coverage drops to roughly 6.4 SF/gal at 1/4 inch and 3.2 SF/gal at 1/2 inch. Use the coverage calculator on this page to estimate quantity before ordering.

Is Carboguard 501 solvent-free?

Yes. Carboguard 501 is 100% solids by volume with 0 lbs/gal VOC. This makes it suitable for use in confined and enclosed spaces with normal workmanlike ventilation.

How large is one kit of Carboguard 501?

Carboguard 501 ships as a 3.6-gallon kit (Part A and Part B), weighing approximately 50 lbs. Shelf life is 24 months at 60–85°F when stored unopened.

What do I topcoat over Carboguard 501?

Carboguard 501 may be topcoated with epoxies or polyurethanes depending on the exposure and service requirements of the project. Maximum recoat window is 30 days for epoxy topcoats and 90 days for polyurethane topcoats at 75°F. If exceeded, the surface must be sweep blasted or sanded before topcoating. Elastomeric topcoats (e.g. Reactamine 760) require abrasive blasting before application.

What is the pot life of Carboguard 501?

Pot life is 15–30 minutes at 75°F (24°C), depending on the volume mixed. Larger batches and higher temperatures shorten pot life. Pot life ends when the material becomes too viscous to use.

Carboguard 501 Epoxy Filler for Concrete & Masonry - 3.6 Gal Kit

Q: What is Carboguard 501 used for?

Carboguard 501 is a 100% solids, solvent-free epoxy patching and surfacing compound used to fill voids, bug holes, narrow cracks, and surface defects in concrete and masonry, and to repair weld seams and pits in metal. It can also serve as a coving material for floor-wall transitions and lap joints. It is substrate preparation — it must be topcoated with an epoxy or polyurethane after cure.

Q: Can Carboguard 501 be used on steel?

Yes. Carboguard 501 is normally self-priming to steel, concrete, and masonry. It is also used to repair weld seams and pits in metal, including potable water service when topcoated with a compatible ANSI/NSF 61 approved lining. Steel must be prepared per SSPC-SP10 with a 1.5–3.0 mil profile; galvanized steel per SSPC-SP16.

Product Specs — Carboguard 501 Epoxy Filler

Carboguard 501 — Two-Component Solvent-Free Epoxy Patching & Surfacing Compound by Carboline.
A 100% solids epoxy used to fill voids, bug holes, and narrow cracks in concrete and masonry, repair weld seams and pits in metal, and serve as a coving material for floor-wall transitions and lap joints. Self-priming on steel, concrete, and masonry. Trowel-applied; high film build with rapid hardening for quick return to service.

✔ 100% solids · 0 lbs/gal VOC • ✔ Mix ratio 1:1 (A to B) • ✔ Pot life: 15–30 min @ 75°F • ✔ 3.6-gal kit

✏️ Need a project quote? Request Online

📞 Questions? Call (800) 567-5358 — Mon–Fri 8AM–5PM EST

Carboguard® 501 by Carboline

Carboguard 501 solvent-free epoxy filler and patching compound for concrete, masonry, and metal repair by Carboline — Carboguard® 501 — Solvent-Free Epoxy Filler (3.6-gal kit, Light Grey)

Shipping Map — Carboline Delivery Timing

Carboline US regional warehouse shipping map showing typical delivery transit zones — Typical transit times vary by destination zone.

Shipping Time

Call (800) 567-5358 for pricing and logistics questions.

Carboline orders ship from regional warehouses nearest to your location, with full product stock maintained at each facility.

Most orders ship within 2–3 business days of order placement. Transit times shown on the map are typical but not guaranteed.

Coverage Rates by Fill Depth

Coverage is highly depth-dependent. Theoretical baseline is 1604 ft²/gal at 1 mil (100% solids). At 1/8" fill (the maximum per coat on a vertical surface), one gallon covers ~12.8 SF. Deeper voids drop coverage proportionally — at 1/2" fill, one gallon covers only ~3.2 SF. Estimate carefully before ordering.

Fill Depth	SF per Gallon	SF per Kit
1/16"	~25.6 SF/Gal	~92 SF/kit
1/8"	~12.8 SF/Gal	~46 SF/kit
1/4"	~6.4 SF/Gal	~23 SF/kit
3/8"	~4.3 SF/Gal	~15 SF/kit
1/2"	~3.2 SF/Gal	~12 SF/kit

Performance Test Data

Test Method	Result
Bond Strength (ASTM D4541, over concrete)	>400 psi — concrete failure
Compressive Strength (ASTM C579)	5000 psi
Flexural Strength (ASTM C580)	2200 psi
Tensile Strength (ASTM C307)	1300 psi
Shore D Hardness (ASTM D2240)	60
Continuous Dry Heat Resistance	250°F (121°C)

Source: Carboline Carboguard 501 Technical Data Sheet, April 2022 (doc S501).

Technical Specifications

Property	Value
Generic Type	Two-component solvent-free epoxy
Color	Light Grey
Solids by Volume	100% ± 2%
VOC	0 lbs/gal (calculated)
Mix Ratio	1:1 by volume (Part A : Part B)
Pot Life	15–30 min at 75°F (depends on batch volume)
Max Per-Coat Thickness	125 mils (1/8") on vertical surfaces; multiple lifts for deeper voids
Application Temp Range	Material 55–90°F · Surface 55–125°F · Ambient 55–110°F
Sandable	8–16 hours after application (depends on conditions)
Set Time to Topcoat @ 75°F	8 hours
Ultimate Cure @ 75°F	7 days
Max Recoat Window	30 days for epoxies · 90 days for polyurethanes (at 75°F)
Topcoats	Epoxies or polyurethanes per exposure requirements
Substrates	Steel (SSPC-SP10, 1.5–3 mil profile), galvanized (SSPC-SP16), concrete, masonry; also over other epoxies
Application Method	Trowel, taping knife, spatula, or rigid squeegee
Kit Size	3.6 gallons (Part A + Part B), ~50 lbs
Shelf Life	24 months (60–85°F, do not freeze)

⚠️ Good to Know Before You Buy

Coverage drops sharply with fill depth. 12.8 SF/gal at 1/8" becomes 6.4 SF/gal at 1/4" and 3.2 SF/gal at 1/2". Measure void volumes carefully before ordering — eyeballing depth can leave you short.
Short pot life: 15–30 minutes at 75°F. Larger batches and warmer temperatures shorten this further. Mix only what you can apply before the material becomes too viscous to use.
Max 1/8" per lift on vertical surfaces. Deeper voids must be filled in multiple passes — let each lift cure (or at minimum partially set) before applying the next.
Self-priming on steel, concrete, and masonry. No separate primer required when applied to properly prepared substrates. Steel: SSPC-SP10 with 1.5–3 mil profile. Concrete: 28-day cure, ASTM D4258/D4259 prep.
Solvent-free, 0 VOC. Suitable for confined and enclosed spaces — tanks, vaults, underground structures — with normal workmanlike ventilation.
This is substrate prep — must be topcoated. After cure, topcoat with an epoxy or polyurethane per project specification. Max recoat window is 30 days (epoxy) or 90 days (polyurethane) at 75°F; past that, the surface must be sweep blasted or sanded before topcoating.
Sandable in 8–16 hours. Useful for finish work where the patch needs to be flush with the surrounding surface before topcoating.

Frequently Asked Questions — Carboguard® 501

What is Carboguard 501 used for?

Carboguard 501 is an epoxy patching and surfacing compound for filling bug holes, voids, and narrow cracks in concrete and masonry, repairing weld seams and pits in metal (including potable water service when topcoated with a compatible ANSI/NSF 61 lining), and coving floor-wall transitions and lap joints. After cure, it must be topcoated with an epoxy or polyurethane per project requirements.

How much area does one kit cover?

Coverage depends on fill depth. At 1/8" depth, one 3.6-gal kit covers approximately 46 SF. At 1/4" depth, only ~23 SF. At 1/2" depth, only ~12 SF. Theoretical baseline is 1604 ft²/gal at 1 mil (100% solids). Allow for loss in mixing and application.

Can Carboguard 501 be used on steel?

Yes. Carboguard 501 is self-priming on steel, concrete, and masonry, and may be applied over other epoxies. It's also used to repair weld seams and pits in metal. Steel substrate must be prepared per SSPC-SP10 with a 1.5–3.0 mil profile; galvanized steel per SSPC-SP16. For potable water service, topcoat with a compatible ANSI/NSF 61 approved lining.

What is the pot life and how long is the working time?

Pot life is 15–30 minutes at 75°F, depending on the volume mixed. Larger batches generate more heat and shorten pot life; warmer temperatures do the same. Pot life ends when the material becomes too viscous to apply. Mix only what you can use within the working window.

Is Carboguard 501 safe for enclosed or confined space use?

Yes. Carboguard 501 is 100% solids and solvent-free with 0 lbs/gal VOC, so it can be used in confined spaces — tanks, vaults, and underground structures — with normal workmanlike ventilation and standard PPE. Always read the SDS and follow project-specific safety protocols.

How is Carboguard 501 applied?

Carboguard 501 is a high-solids thixotropic compound applied with a steel finishing trowel, taping knife, spatula, or rigid squeegee. Use the surrounding substrate as a leveling guide for finishing. Maximum thickness per coat is 1/8" on vertical surfaces; deeper voids must be filled in multiple lifts. The product is sandable 8–16 hours after application.

What do I apply over Carboguard 501 after it cures?

Carboguard 501 may be coated with epoxies or polyurethanes depending on the exposure and service requirements. Set time to topcoat at 75°F is 8 hours; ultimate cure is 7 days. Maximum recoat window is 30 days for epoxies and 90 days for polyurethanes at 75°F. If exceeded, the surface must be sweep blasted or sanded before topcoating. Elastomeric topcoats (e.g. Reactamine 760) require abrasive blasting before application.