Monument Repairs with Epoxy

March 9, 2016

A technician who uses a product to repair tombstones wrote me recently looking for help with problems that he was having. He goes on to say that the epoxy that he uses never fails, but rather the stone fails. When a secondary break occurs, the stone always re-breaks about 2 mm (about ¾ inch) above or below the epoxy joint. The epoxy attached to about 2 mm of the stone and holds well.

He asked me if the epoxy shrinks so much that it will ‘ pull away ‘ from the stone it’s attached to, and in his case, it pulls about 2mm of stone with it.

No I doubt it is epoxy shrinkage causing the problem. High quality epoxy has little or no shrinkage. It would have to be a very poor quality epoxy to be shrinking enough to do that.

The reason his epoxy is not working is that it is too rigid. His existing rigid material has a “high modulus of elasticity”. A material with “high modulus of elasticity” is a material that is stiff and/or rigid. A “low modulus of elasticity” material is semi-flexible, and is not rigid or brittle.

T pieces of the stone structure (in this case a tombstone) and pieces not in touch with the ground tend to get hotter and cooler faster than the larger pieces and pieces with ground contact. This is called “differential timing of the event”. For example the top of a tombstone can be heated and cooled on 5 sides, the top and the 4 sides. The base of the tombstone which is buried in the ground has earth or stone on all of its surfaces. This earth and stone tends to keep the temperature of the base more stable by insulating it and slowing the change in temperature. This works much like the insulation in your house slows temperature changes inside your house.

When an object like a piece of stone is heated it expands (gets bigger). When an object cools it contracts (gets smaller). For example 100 feet of concrete will be 1 inch longer once it is heated 100 degrees F. That is why expansion joints are cut into concrete.

In the case of tombstones all the pieces of the same type of stone have very similar if not identical “coefficient of expansion”. Since the pieces are positioned with potentially different timing of heating and cooling there is a “differential timing of the event” (see above). The result is stress areas you are seeing in the closest weakened plane in the stone near the bond line.

Product #2005 was specifically designed for tombstone (monuments) and/or stone bonding, or repair. Product #2005 is very strong yet it is has a “low modulus of elasticity” (semi-flexible). The low-modulus of elasticity helps to absorb differential movement (two sections of stone heating and cooling at different times), making it much less likely to cause a stress area in adjacent weakened planes.

Camouflage the bond line rubbing stone dust(ground off the original stone or a similar colored stone) into any exposed epoxy material while the epoxy is still “wet”. That way the dust will stick in the wet epoxy making the epoxy difficult to impossible to see.

Please send your additional question and blog ideas to

Selecting the Right Floor for a Mechanical Room

July 27, 2015

Mechanical Room Floors are very unique in their use and conditions. You have to consider the installation environment and the function of the floor. Our Mechanical Room Floor will protect the concrete, and contain any liquids that spill.

Systems used in mechanical rooms should be zero VOC. You do not want solvent evaporating from your material. Evaporated solvent could be picked up by your air handling unit sending it through your building. The best way to prevent this is with a VOC free 100% solids resin system. A resin system that is 100% solids has no solvent (or water) in it. It also means when you spread a gallon of material on your floor after it hardens you still have a gallon of material. With water-based and solvent based materials you lose half the material to evaporation.

Mechanical rooms should be chemical resistant. Typically they are top coated with Product #2 Chemical Resistant Epoxy – If it is a chemical feed room you can supply a list of chemicals and concentrations to the technical support department so you can make sure the #2 is chemical resistant enough.

The systems used for mechanical rooms are impact resistant. The limiting factor is the strength of the concrete substrate. Properly installed the epoxy will stay bonded to the concrete. The only way the epoxy can chip is if you chip the concrete from underneath the epoxy. You can install a thicker epoxy floor for an additional cost if you think you need still additional protection.

The systems recommend for mechanical rooms are highly abrasion resistant and will easily handle traffic up to heavy fork lift traffic. The system can be made even thicker if you have an unusual amount of abusive traffic.

When the mechanical room is over a finished space, it is suggested that a crack isolation membrane be integrated into the system. This can be done with Product #32 Epoxy Membrane System. The advantage of #32 Epoxy Membrane Resin as part of the system is 100% solids and has zero VOCs.

If the mechanical room is shut down and you can handle solvent and want something still more flexible you can use Product #459 a two component, high solids, elastomeric urethane instead of or in addition to the Product #32 Epoxy Membrane above. Product #459 exhibits excellent elongation properties along with high tensile strength and tear resistance to make it an ideal crack resistant membrane for use under Product #2 and all of our other epoxy mechanical room floor coatings.

One of the primary reasons you need a mechanical room floor over finished space below is to waterproof it. The above methods accomplish the waterproofing in the center of the floor. The edges of the floor can be protective with a coving material up the wall and around pipe penetrations. That can be accomplished with Product #720 Epoxy Coving Resin System which can be used to install an integral cove base for all of our epoxy based mechanical room flooring and most of our other epoxy flooring and coating systems. This provides seamless wall to floor protection.

For more information on seamless water and chemical resistant mechanical room flooring, contact Technical Support Department at 352-533-2167, or email me at


%d bloggers like this: