Concrete Crack Healer and Sealer

October 7, 2025

Fast Crack Healer and Sealer for Concrete Floors

When concrete floors start to show signs of cracking or surface wear, repairing them quickly and effectively can prevent costly downtime. Epoxy.com Product #684LV is a methyl methacrylate (MMA) resin system designed to penetrate, bond, and seal concrete surfaces — not just on bridge decks, but anywhere durable protection is needed.

What Makes #684LV Different

Unlike typical epoxies or sealers, #684LV is ultra-low viscosity and fast-curing. It seeps deep into cracks and pores in the concrete, restoring structural integrity while sealing out moisture and contaminants. Once cured, it forms a clear, tough, chemical-resistant surface that can be top-coated or left exposed.

Fast cure: typically 30–45 minutes even at low temperatures.
Deep penetration: bonds within the concrete matrix.
Chemical resistance: excellent for acids, fuels, and solvents.
Low downtime: floors can be reopened to traffic within an hour.

Ideal Uses Beyond Bridge Decks

While #684LV is trusted for infrastructure work, it’s equally effective in:

Industrial plants and warehouses – quick repairs between shifts.
Food and beverage facilities – sealing cracks to prevent bacterial growth.
Retail and commercial floors – keeping polished concrete from spalling.
Chemical and wastewater facilities – long-term protection from vapor intrusion.
Parking decks and ramps – extending the life of exposed slabs.

Wherever rapid turnaround and strong bonding are required, #684LV is a proven performer.

Application Notes

Prepare the surface by cleaning and drying the concrete thoroughly.
Flood-coat or broom-apply #684LV until refusal — allow penetration.
Optional broadcast: silica sand for slip resistance or mechanical profile.
Reopen to traffic within approximately one hour (temperature dependent).

For severe cracking, the material can also be pressure-injected to restore internal bond.

The Bottom Line

Epoxy.com Product #684LV gives contractors and facility managers a fast, permanent way to stop cracks before they grow — without waiting days for cure time. It’s a simple, reliable solution for extending the life of your concrete floor systems.

For more information contact:

Epoxy.com
A Division of Epoxy Systems, Inc
A Vermont Corporation
USA

We have products that have passed the test of time as well as the best new Systems available today.

Since 1980 – 40 years of the highest quality products

Hours: 9AM-4PM Eastern Time (6AM-1PM Pacific Time)

Closed for lunch from 12Noon to 1PM

321-206-1833  Customer Service – Ordering and Order Status
                         Katey Lambert-Fontaine, VP – Chief Operations Officer
                         sales@epoxy.com

                        Technical Support
352-533-2167  Norm Lambert, President – Technical Support Director
                         info@epoxy.com

Leave a Comment » | Bonding systems, Bridge Concrete Repair, Concrete Infrastructure Repair, Epoxy, fast setting, Methyl Methacrylate (MMA), MMA Crack Healer and sealer, Winter cure, Winter installation | Tagged: chemical resistant coating, concrete repair, crack healer, epoxy flooring, epoxy instalation, fast cure sealer, Floor protection, industrial maintenance, MMA sealer, Product #684LV, vapor mitigation | Permalink
Posted by Norm Lambert

Patching Floor with Epoxy

July 18, 2017

Here is an outline of the procedure for patching with Epoxy.com Product #1 and Product #10. Cold cure is identical but you should make even smaller batches and work even faster.

Mix a small amount of the #10 (mix ratio 2A: 1B).
1. Measure accurately and mix for 3 minutes with a proper size mixer.
2. Typically very small batches less than a quart can be mixed with a stir stick.
3. Larger batches should use a mixing paddle in a low speed drill or similar. Typically mixing paddles are 5 inches or more in diameter.
Apply a primer coat of #10 at a rate of 250-300 SF per gallon (typically done with a roller) to the substrate the mortar is to be attached to.
1. Typically you will allow this to harden to the touch to make troweling into it easy.
2. You can trowel into the wet primer in the case of small patches.
Mortar Patch
1. Mix another small batch of #10, using the methods in step 1 above.
2. Add Product #82 Mortar Blend Aggregate to the mixed resin in 3a. You can add as much as 50 to 75 lbs. of mortar blend aggregate to a gallon of mixed #10 resin. If the material appears to wet you can add more, if it is too dry add less.
3. Quickly trowel the patch into place. Winter Cure Epoxy can set very fast in the bucket.
Sealer Coat
1. After the patch in step 3 has hardened, you can grind off any high spots and fill more material again if needed.
2. Then seal the top of the patch.

Product #10 is thinner than the #1, making it an excellent sealer for sealing up the patch.
Alternately you can go directly to a very thin coat of #1

Top Coat
1. Mix small batches of #1 using the methods used in #1 above.
2. Mix optional Antiskid fine into the coating above at a rate of 8-16 volume ounces of Anti-skid per gallon of mixed resin. 12 ounces per gallon is typical. This is done by mixing the resin first, adding the anti-skid and mixing for another min.
3. Quickly apply the material with a roller at a rate of 160-200 SF per gallon per coat. Two coats is recommended.
Please read all the information below before starting your project.

Do with Epoxies
Don’ts with Epoxies
Surface Preparation
www.epoxy.com/10.aspx
http://epoxy.com/1cold.htm
SDS Product #10 Part A – Hardener Lo-Mod Epoxy Adhesive and Mortar Epoxy Resin
SDS Product #10 Part Cold Cure B – Lo-Mod Epoxy Adhesive and Mortar Epoxy Hardener
SDS Product #1A – All Purpose Coating Hardener Component MSDS.
SDS Product #1B -cc – Cold Cure Epoxy Hardener for Product #1

BE SURE TO CALL ME WITH ANY QUESTIONS OR CONCERNS!

Leave a Comment » | Bridge Concrete Repair, concrete dam repair, concrete infrastructure bridge repair, Concrete Infrastructure Repair, Concrete Repair, Epoxy, epoxy concrete floor patch, epoxy education, repairing concrete with Epoxy, Seamless Epoxy Flooring Systems, Structural Repairs | Tagged: Epoxy, epoxy resin, Floor Patching Epoxy, installation tips, Pot hole filling epoxy, primer | Permalink
Posted by Norm Lambert

Epoxy Injection of Structures Part 3

February 24, 2017

This is the third in a series on Infrastructure Repairs Using Epoxy. Part One is Introduction to Epoxy Injection. Part 2 is Crack Analysis Before Epoxy Injection

If your have not read that yet you may want to go back and read it before you proceed with reading this.

Port Setting

It is extremely important that if drilling to use the right tool. to set drill type ports use a vacuum swivel drill. That is a drill with vacuum attached swivel drill chuck and hollow a drill bit.

Concrete dust can be detrimental to the injection processes in several ways. Any dust remaining in the drill hole near a crack can combine with the very low viscosity injection resin. This thickens your resin turning it into a weak paste. This paste can slow or even block the resin flow. Drilling very tight crack with a solid drill forces dust into the crack. This seals the crack from resin flow. Do not allow shortcuts in the drilling procedures! However, for most applications the surface port is the easiest and most effective method.

Port Spacing

Determining the spacing of ports is done by a highly experience applicator. This spacing is a factor of the tightness of the crack and the depth of the concrete substrate. Spacing is normally between four (4) and eight (8) inches.

Port Setting and Sealing

Align ports directly over cracks. That allows injection resin to flow into the crack. Seal surface cracks. Sealing the exterior of cracks is done with Epoxy Gel type Bonder.

Testing The System

Test cracks that are ill defined, or if dust or debris is in the crack. This testing may be done by injecting water into the crack area.

Water left in the cracks will not effect the injection process or the curing of the Epoxy.com Injection Resin. Heavier injection resin forces the water out the cracks. Water injection helps clean the cracked areas. More important, is that it helps avoid the unexpected. This process of flushing the cracks is commonly skipped by more experience contractors, who can tell if there will be a flow of resin, by just looking at them. However, when in doubt water testing is a must.

If the cracks contain algae, chlorinated water containing copper sulfate is injected. After pumping this mixture is left over night. The next morning the crack is flushed by pumping fresh water, into it. This flushes it out before resin injection begins.

Efflorescence builds up on the bottom of a crack in a horizontal slab. Water in the crack extracting soluble calcium hydroxide is the cause. The water evaporates at the surface leaving the lime, which later reacts with the carbon dioxide in the air to form limestone. The inside of the crack, is frequently free of limestone and making it suitable for injection.

Part 4 of this series: Injection Resin Materials Product Selection.

For more information visit our website at http://www.epoxy.com, email us at info@epoxy.com or call our technical service department at +1 (352) 533-2167.

1 Comment | adhesive, Bridge Concrete Repair, Concrete Bridge Pier Repair, Concrete bridge repair epoxy, concrete dam repair, concrete infrastructure bridge repair, Concrete Infrastructure Repair, Concrete Repair, concrete wall repair epoxy, Epoxy, epoxy concrete repair, epoxy injection, Infrastructure Repair, Injection, Installation, repairing concrete with Epoxy | Tagged: concrete structural repair epoxy, epoxy grout injection, epoxy injection, epoxy injection bridges, epoxy injection concrete, epoxy injection port setting, epoxy structural repairs, epoxy structural repairs concrete | Permalink
Posted by Norm Lambert

Epoxy Injection of Structures Part 2

February 14, 2017

Infrastructure Repairs Using Epoxy

Epoxy Concrete Injection Epoxy Wood Injection, epoxy crack repair

Epoxy Structural Concrete and Wood Repair / Waterproofing

The following article is written with enough information about resin injection systems to help protect the Owner from the misuse or improper installation of an injection systems. For more information contact me: Norm Lambert.

This is the second in a series on Infrastructure Repairs Using Epoxy. Part One was Introduction to Epoxy Injection. If your have not read that yet you may want to go back and read it before you proceed with reading this.

Part 2: Crack Analysis Before Epoxy Injection

As with all repair and rehabilitation of concrete, the initial job analysis is by far the most important step. Epoxy Injection Resin will weld concrete cracks but, of course, will not repair the cause of the cracking.

Analyze each potential injection application to determine the exact cause or causes of the cracking. Correcting the cracking problem can be fairly simple, or may be difficult involving design changes.

Consult a structural engineer when design changes are necessary. Do this before starting the injection. Repairing cracks by Injection is effective after these design changes. Prevent future cracks by fixing the original cause of the cracking, when ever possible.

Parking garages are an example of cracking problem that require a structural engineering analysis. Epoxy.com Epoxy Inection Often inadequate design for expansion/contraction is the cause for parking garage structural cracking. Avoid weld injecting a crack if there are not enough expansion joints. Sometimes flexible overlays such as Epoxy.com System # 495 can be used to overcome this defect. This does not however encapsulate the rebar in a way that will totally stop the premature deterioration of the steel. Often times additional joints are needed, thus the analysis of cracking problems is critical.

Bridge decks and slab on grades can often be repaired with Epoxy.com Product #684LV crack healer and sealer and save some of the cost of doing epoxy injection.

Next in the Injection Series:

Part 3: Setting Epoxy Injection Ports