Substrate pH Testing
No surface preparation plan succeeds without checking the chemistry, as the running record epoxy flooring allen tx all saints of america holds shows that even a perfect diamond grinding job fails if the alkalinity ruins the bond. This issue often crops up on a fresh concrete slab in Allen, TX, where the high pH levels interfere with the epoxy. You cannot just pour a primer and hope for the best.
The chemistry of concrete alkalinity
Concrete is naturally alkaline. When it is newly poured, the pH levels can reach 12 or 13. If you apply a base coat or a polyaspartic system to a surface with high alkalinity, the chemical reaction will be compromised. This leads to delamination or a soft, gummy finish that never fully cures. Testing the pH is a mechanical necessity before any resin hits the floor. You need to know if the alkalinity will neutralize the hardener in your epoxy system.
Methods for measuring pH levels
Most guys on the job use pH indicator strips or liquid testing kits. You apply a small amount of distilled water to the surface, let it sit for a moment, and then use the strip to get a reading. If the reading is above 9, you are in the danger zone. Some crews also run a moisture test or a calcium chloride test to ensure the slab is stable. High moisture and high alkalinity together are a recipe for total coating failure. It is better to wait for the slab to cure fully than to rush a polyurea application on a reactive surface.
Preparing the surface for testing
You should perform these tests after the initial grinding. Once the diamond grinding has established the correct surface profile, the testing becomes more accurate. If you test through a layer of dust or old sealer, your results will be lies. Make sure the area is clean and dry. If you see a spall or a deep crack, address those with a proper joint filler or crack repair before you worry about the pH. The chemistry of the resin depends on a clean, stable, and neutral substrate.
Managing high pH results
If the testing shows the slab is too alkaline, you have a few options. You might need to wait longer for the concrete to carbonize naturally. Sometimes, a specialized primer designed for high pH environments is required. If you are planning a decorative floor with a flake or quartz sand broadcast, the bond must be absolute. A failure in the chemical bond means the entire decorative layer will eventually peel up, regardless of how much color or metallic pigment you used in the topcoat.