Interior Flooring Manual
Why Patches Fail and How to Prevent It When a patching compound is force dried, improperly mixed, or mixed with too much water, the patch is prevented from reaching full cure strength. Loss of strength can cause indentations when exposed to heavy point or rolling loads. Typical reasons for problems associated with floor patching compounds include: Using substandard products. Over-watering or using additives not called for by the manufacturer of the patch. This weakens the patch and causes loss of “internal cohesion” and shear resistance, ultimately reducing cured compressive strength. Force drying, which stops the hydration process needed to develop full cure strength. Using a patching compound that is incompatible with the substrate.
Note: Priming the subfloor makes application of properly mixed patching and smoothing products easier and increases their performance. Check with the patch manufacturer for primer recommendations.
Self-Leveling Underlayment Self-leveling underlayments are an alternative to traditional hand troweled smoothing that can save time and money. Once poured or pumped into place, these products seek their own level to provide a flat, smooth surface. Self-leveling underlayments may be applied over virtually any dry, cured, clean, solid, and properly prepared substrate. Use primer as directed by the underlayment manufacturer. All self-leveling underlayments used with Lonseal flooring must be Portland cement-based and cure to 4100 psi (28.3 MPa) or greater at 28 days.
Note: Always check with the underlayment manufacturer for suitability of use in your application, including moisture- related issues.
Bond Tests Lonseal always recommends that a bond test be performed, regardless of substrate or underlayment. A bond test will help the installer to test the overall bond and compatibility of the flooring system, which includes the primer (if used), patching compound or self-leveler, and adhesive. The bond test should be performed at various locations throughout the installation area by adhering 2 ft. x 2 ft. (0.6 m x 0.6 m) minimum pieces of flooring following the installation instructions detailed in this manual. Allow a full 72 hours for the adhesive to cure. Removal of the flooring should be difficult, and there should be some form of cohesive failure between various components of the flooring system. If failure occurs solely at one level of the installation, there may be an issue and the manufacturers of the products involved should be consulted. Additional guidance for performing bond tests may be found in ASTM F3311. Other benefits to a bond test are: While applying the adhesive, the installer can get a feel for the appropriate open and working times for the installation area. This is especially useful when installing in an area where a system other than a permanent HVAC is being used to control the temperature and humidity. Allows the installer to verify the suitability of the adhesive for use with the substrate, as well as determining the appropriate trowel size and spread rate, when dealing with a porous or non-porous surface. When an end-user will subject the flooring to heavy rolling loads (e.g. money carts, freight dollies, clothing racks, tool chests, pallet jacks, hospital beds, etc.) they have the opportunity to repeatedly roll these loads over the adhered flooring, to determine if the system may be deemed fit for the application. Using a larger piece of flooring than noted above for this type of situation is recommended. Note: For small scale or specialty projects, the test size may need to be adjusted, but should still be sufficient to ensure compatibility can be tested.
LONSEAL ®
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Revised: 9.20.2024
Disclaimer: Printed documents are uncontrolled. Always refer to www.lonseal.com for the most current technical information.
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