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.  


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


Moisture Tolerant Epoxy

October 23, 2017

Moisture Tolerant

Epoxy Primer

and Base Coat

Epoxy.com Product #100

Can be Used as a Primer Over Concrete as New as 5 Days


Epoxy.com Product #100 Moisture Tolerant Primer and Base Coat consists of a unique water based epoxy technology which allows the contractor to install epoxy resin floor systems and other moisture sensitive floor coverings on new concrete (5 days old) without fear of moisture entrapment. Epoxy.com Product 100 Moisture Tolerant Primer and Base Coat is applied in a two coat application. Epoxy.com Product 100 Moisture Tolerant Primer and Base Coat is the primer/basecoat used in various Epoxy.com Products

Epoxy.com Product #100 Moisture Tolerant Primer and Base Coat is a unique two-component, moisture tolerant, extremely high density, chemically enhanced epoxy based product which reduces the passage of water vapor and moisture through slabs on, above or below grade, thus eliminating delamination and blistering of adhesives, floor coverings, resin floor systems, epoxy terrazzo and coatings.

Epoxy.com Product #100 Moisture Tolerant Primer and Base Coat controls water vapor transmission levels for the installation of most floor covering systems, including VCT, sheet vinyl, carpets, wood, laminates, epoxy resin flooring and epoxy terrazzo.

Advantages

  • Vapor and water barrier.
  • Can be placed on new concrete in as little as 5 days.
  • Water based – low VOC.
  • Highly moisture tolerant
  • Barrier against radon and other gasses
  • Compatible with most flooring systems – conventional, and seamless epoxy flooring systems.
  • Does not support the growth of mold.
  • Easy to install with little down time.

Considerations

  • Substrate must be at least 50° F during installation and curing
  • Substrate must be free of dirt, sealers, waxes, and other foreign materials that would interfere with proper bonding.
  • Must be installed a minimum of 1/8 for use with moisture sensitive floor coverings.

 

Application

Surface preparation

Surface preparation is the most critical portion of any successful resinous flooring system application. All substrates must be properly prepared as outlined in Epoxy.com Surface Preparation Procedures. Epoxy.com Technical Support Department is pleased to answer any questions.

Mixing

Epoxy.com Product #100 Moisture Tolerant Primer and Base Coat is a two-component material. Do not alter mixing ratios in any way. Part I and Part II are supplied in the correct mixing ratios. Always mix a complete unit in the proportions supplied.

Stir material for approximately 3-4 minutes to form a homogeneous consistency using a slow speed drill and “Jiffy” blade. Do not entrap excessive air. Scrape all sides and bottom of container to ensure thorough mixing.

Priming

Prime using Epoxy.com Product #100 Moisture Tolerant Primer and Base Coat thinned 10% with one (1) pint of potable water per 1.25 gallon unit for good
penetration. Apply with a squeegee and short nap roller to the properly prepared substrate. Back roll with the short nap roller to achieve a uniform coverage. Allow to cure hard enough for foot traffic, about 3-4 hours at 75 degrees F.

Body Coat

Apply one (1) Part of Epoxy.com Product #100 Moisture Tolerant Primer and Base Coat to 4 parts of B. Thoroughly mix with a low speed drill and Jiffy blade until uniform. Mix with low speed drill until uniform and no lumps. Apply with trowel, or squeegee. Allow to self-level and backroll with a looped roller. A 1.25 gallon unit will
cover 30 sq. ft. @ 1/16″.

Broadcast surface with broadcast sand to excess (30-50 lbs./100 sq. ft.) with Epoxy.com Product #77 to achieve 1/8 inch. Sweep and vacuum excess or loose sand after hardening (16-24 hours, depending on temperature).

Top Coatings and Overlays

Apply top coatings or resin floor system directly over broadcast surface. Prime surface with appropriate Epoxy.com primer as required. For vinyl flooring and other floor coverings consult with manufacturer of floor covering.

Physical Properties

Material 2-component epoxy
Density 12.70 lbs/gallon
VOC Content, Mixed < 1 g/L
Solids by Volume 59%
Flash Point: Part A

Part B

>212°F

170 °F

Mixing Ratio 1:4 by Vol.
Pot Life, Approximate 60 minutes @ 75°F (24°C)
Open to Foot Traffic After 16 hrs. at 73°F (23°C)
Curing Temperature Minimum 50°F
Full Cure and Maximum Resistance 7 days
Hardness, Shore D ASTM-D-2240 70-75
Compressive Strength  ASTM-C- 579 6500 psi
Flexural Strength ASTM-C-580 2100 psi
Adhesion To:

-New concrete (5 days)

-Moist concrete (28 days)

-Dry concrete (28 days)

 

110 psi

550 psi

580 psi

Temperature Resistance:

a)Continuous:

-Dry heat

-Humid

b)Intermittent:

-High pressure water

-Dry heat

140°F (60°C)

113°F (45°C)

185°F (85°C)

149-185°F (65-85°C)

Maintenance

After completing the application of Epoxy.com Product #100 Moisture Tolerant Primer and Base Coat and the topcoats or floor covering system, the installer should provide the owner with maintenance instructions relevant to the specific topcoats or floor covering. If floors become slippery due to animal fats, oil, grease, or soap film, clean and rinse thoroughly.

More Information

For more information please visit our website at http://www.Epoxy.com, email me at norm@epoxy.com or call Epoxy.com Technical Support Department at 352-533-2167.


Extending The Epoxy Install Season

October 17, 2017

Cold Temperature Epoxy

Installing Epoxy on Garage Floors in Cold Temperatures

Extend Epoxy Installation Season into Winter

It is that time of year again when I start getting  a lot of calls and emails about installing epoxy in cold temperatures. epoxy_color_chart_s

The best time to protect your floor is before it sees any salt at all. If you have a new garage floor now is the time to protect it.  It is still possible to do older floors but the more salt it sees the more difficult and expensive it can be.

The night temperatures are dropping this time of year. It is still possible to coat your garage floor before temperatures drop too low. Our cold temperature epoxies will cure with substrate temperatures as low as 35 degrees F, although it will set a lot faster at 40 degrees F.

Protecting your garage floors is especially  important in areas that will see salt from roads or ocean spray.  You will want to protect your garage from the ravaging effects of salt deterioration. Without protecting your floor salt will damage your garage floor and make for very expensive repairs later if it is not well protected.

It is not too late to protect your floor even in cold climates if you move quickly now.  Without this protection your garage floor will not be as nice come spring as it is now.  The damage that takes place is not only aesthetic but structural.

Cold Temperatures Epoxies

Cold Temperature Cure Epoxy Resins allow installation to be done at low temperatures as low as 35°F., (although it sets a lot faster at 40°F) expanding your epoxy coating and epoxy flooring installation season. Epoxy.com Cold Temperature Cure Epoxy Resins can also be used in cold storage areas like food processing areas, where the temperature cannot be raised higher than 35° F or so. Normal cured epoxy typically requires 50°F or more.

Depending on how you mix the aggregate into the products below, they can be used as a mortar for overlays, or a grout for sealing between other hardened construction materials.

Commonly Used Cold Temperature epoxies

Product #1 Cold Temperature Cure Epoxy Coating is 100% solids and specially formulated coatings for cold temperature applications. Cold Temperature Epoxy Coating #1 is able to cure at temperatures as low as 35°F. It has Zero (0) VOCs. Since it has no VOCs, it has no solvent so it meets the strictest possible standard for a low VOC coating. It is often used in coolers and food preparation areas that require constant low temperatures. Product #1 Cold Temperature Cure Epoxy Coating is also frequently used in room temperature applications to meet super-fast cure, limited shutdown needs.

Product #10 Cold Temperature Curing Epoxy Mortar Resin – This product has a low modulus of elasticity (flexibility) and is Low Viscosity. The low viscosity allows heavy loading of the right fillers. The heavy filler loading helps not only to save money, but helps to maintain better thermal coefficient with respect to concrete and steel. The low modulus of elasticity prevents it from being brittle making it less vulnerable to thermal coefficient differences. It also gives it better impact resistance.

You can find more information on cold temperature cured epoxy at: http://www.epoxy.com/EpoxyColdCured.aspx.

Please send me your questions to me by email to norm@epoxy.com


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