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

  1. Prepare the surface by cleaning and drying the concrete thoroughly.
  2. Flood-coat or broom-apply #684LV until refusal — allow penetration.
  3. Optional broadcast: silica sand for slip resistance or mechanical profile.
  4. 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: , , , , , , , , , , | Permalink
Posted by Norm Lambert

Why Epoxy.com for Mechanical Room Floors

October 1, 2024

Epoxy.com products are highly recommended for shop floors due to their durability, chemical resistance, and ease of maintenance. Here are some key benefits:

  1. Durability: Epoxyc9j coatings create a tough, long-lasting surface that can withstand heavy traffic and machinery, making them ideal for shop floors.
  2. Chemical Resistance: These products are resistant to a wide range of chemicals, including oils, solvents, and cleaning agents, which is crucial for environments like machine shops.
  3. Ease of Cleaning: Epoxy floors are non-porous and seamless, making them easy to clean and maintain. Spills can be wiped up quickly without staining the floor.
  4. Safety: Epoxy coatings can be made slip-resistant by adding anti-skid additives, enhancing safety in the workplace.
  5. Aesthetic Appeal: They provide a glossy finish that can improve the overall look of the shop floor, making it more professional and inviting.

Would you like more detailed information on a specific product or application process? For help email me norm@epoxy.com or call me at 1-352-533-2167.

Leave a Comment » | adhesive, Chemical Resistance, Chemical Resistant Epoxy, Chemical Resistant Paint, Concrete Bridge Pier Repair, Concrete Infrastructure Repair, concrete wall repair epoxy, Conductive Epoxy, crack isolation epoxy, Electrostatic dissipative, Epoxy, epoxy concrete repair, epoxy injection, ESD, Novolac, patching concrete with epoxy patching material, seamless epoxy cove, spark free epoxy floor, spark free floor, waterproof, Waterproofing | Tagged: , , , , , , , , | Permalink
Posted by Norm Lambert

Mitigation of Concrete Slab Chemical Vapors

January 29, 2020

How do I stop chemicals gas vapors from contaminated soils passing though a concrete slab? This is a question I get frequently from owners and environmental mitigation experts.

Background

Chemical contamination vapors tend to pass though a concrete slab and get into the air above. Stopping the migration of the gas through a slab is frequently a requirement of repurposing a space.

The following steps can be used to mitigate chemical vapors into your space above it. Without the right tools these vapors in the air from contamination under that slab can be quite pervasive.

Each job needs to be evaluated on an individual bases. The tools below make the solution less evasive.

Cracks through the Concrete Slab

The most direct way for soil contamination gasses to get in is through cracks. Cracks are the path of least resistance, so most of your vapors come through cracks in the floor. That is a very easy fix Product #684LV – Methyl Methacrylate Crack Healer and Sealer.

The #684LV has about the viscosity (thickness) of diesel fuel. That makes it easy to gravity feed into small cracks small porous areas of the concrete. It welds the cracks back together with a bond strength that is greater than the tensile strength of the concrete. In other words structurally you have the monolithic structure that the concrete was intended to be.

Expansion Joints

Expansion joints are the also a very direct route for vapors to come in. To seal these joints use Product #632 – Chemical Resistant Joint Filler. This is a highly chemical resistant joint filler. It will not only keep the vapors out. If there is going to be a chemical exposure to the surface there will it will stop the chemicals from attacking your concrete and further contaminating the soils below it.

Sealing the Surface of the Concrete Slab.

The next step is to prime the concrete with Product #12 Chemical Resistant Primer / Sealer.

This is where there is a couple of ways to go. You can apply an additional coat or coats of the #12 or go on to Coating the Concrete Slab below. Our optional translucent Synthetic Anti-Skid Fine may be added to the #12 if it is used in additional coats as a clear sealer.

The Product #12 Primer Sealer can also be mixed with silica sand and used as a patching material for potholes and otherwise damaged concrete if required.

Coating the Concrete Slap 

In many cases you will want to install a coating over the concrete slab.  There are a number of options for doing this but here are a few of the most common ones.  The biggest difference between these coatings is the chemical resistance. Please See Chemical Resistance Chart for a comparison of chemical resistance of the products below. All of these products are 100% solid, zero voc.  All of the coatings in this section are highly durable and resist the abrasion of traffic. 

UV Resistant Top-Coating

For jobs that will see direct sunlight.  It may be desirable to add an ultra violet (UV) Resistant top coating for the systems above.  

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Posted by Norm Lambert

Epoxy Mortar Installation

June 19, 2019

Epoxy.com Mortar Systems can be used to make permanent repairs that no other kind of product can make. The purpose of this blog is to give you an overview of what you can use and how to use it.

  1. Product Selection –  The following are a list of Epoxy.com Products that make excellent epoxy mortars  All the products listed below are zero (0) VOC, so it meets even the strictest low VOC requirements, and meets Indoor Environmental Quality/Air Quality (LEED IEQ 4.2 Indoor Emitting Materials Credit). See the individual product component technical data sheets and MSDS for further information.
  2. INSTALLATION:
    • First and foremost is good surface preparation.  Good surface preparation is necessary for most if not all patches to have long term success: www.epoxy.com/surfaceprep.aspx.
    • Prime the bottom of the whole with some of the neat mortar resin. Neat mortar resin is the liquid (A&B) mixed at the proper mix ratio and stirring in a way to insure a completely mixed product.  This will typically take about 3 minutes.
    • Mix some of the neat epoxy into the Epoxy.com Mortar Blend Aggregate #82 or other appropriate dry clean silica sand gradation.
    • The amount of sand aggregate depends on the aggregate used. 
      • Typically, the Epoxy.com Product #82 Mortar aggregate can be added at a rate of 18 to 27 lbs. of #82 per 1.5 Qt of mixed resin (1Quart of A to ½ Quart of B).
      • You will need to recalculate the sand above when using a different sized batch. This is doubly true if using one of or 4:1 mix ratio material.
      • Shallow patches tend to be a smaller amount of sand filler.
      • Deeper patches tend to be on the higher side.
      • If you get a lot of resin to the surface your mix is too wet.  If your mixture after it hardens is porous, or weak then you have added too much aggregate.
      • For a better finish in very deep pours do it in 2 lifts. 
        • Fill all but the last ¼ inch plus or minus with your dryer mix. Allow to cure hard (typically overnight).Fill with a wetter mix on top of that after the first one has cured.
        • To ensure proper adhesion between layers never wait more than 24 hours between layers.
      • It is always better to have your patch slightly higher rather than to low.  If you are slightly high you can grind the patch back to level. If to low you will need to fill again. 
    • For very shallow fills (1/32 or so) where the sand particles are to large you can use any of the following:

As always, when in doubt contact me at Epoxy.com Technical Support with your questions.

norm@epoxy.com
1-352-533-2167

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Posted by Norm Lambert

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