It is important for cement board (and fiber cement board) to be installed in strict accordance with the written instructions of the board manufacturer. This typically includes taping the corners and seams with mesh tape and covering the tape with a polymer-modified, cement-based tile mortar. MAPEI's Mapelastic AquaDefense should not be used to replace this critical step or bridge the gaps between cement board.

Open time, sometimes called flash time, describes the amount of time that we want the freshly troweled adhesive to remain open to the elements before you start installing floor covering. There is a good reason why open time needs to be followed: Many water-based adhesives need a little time to start evaporating and letting some of the water out before you start installing flooring. Moisture-curing adhesives need to be exposed to atmospheric humidity to get the reaction started. Again, if you start installing before allowing for the recommended open or flash time, you run the risk of a delayed curing time, which can lead to placement problems and long-term performance issues.

Concrete can be placed in a wide range of ambient conditions. ACI guidelines explain the range of these conditions. Avoid placing concrete below 40°F or above 120°F without proper protective measures. Also avoid windy conditions without a wind break as this will expose the fresh concrete to premature surface drying, which can lead to cracking or a weakened surface that is prone to “dusting” and discoloration.

MAPEI's Keracolor U grout is unsanded. So, it's a great choice for grouting most installations of glossy wall tile. Other good options are Ultracolor Plus FA grout and Ultracolor Plus Max grout. When grouting installations of antique or handmade wall tile, it is recommended to build a mockup (sample board) or, at the very least, test these products in an inconspicuous area before grouting.

After treating corners and seams of cement board with mesh tape and a polymer-modified, cement-based tile mortar, the area should be allowed to cure for at least 24 hours before the application of MAPEI’s Mapelastic AquaDefense. Note: If time is an issue, use a MAPEI rapid-set, polymer-modified mortar with the mesh tape and allow the area to dry for at least four hours before the application of Mapelastic AquaDefense.

This term refers to the amount of time, after the open time or flash time (if any), during which the adhesive you just applied will accept the flooring material and still provide an adequate bond. If you leave certain adhesives open to the atmosphere for too long, they will skin over or cure out and not be wet/sticky enough to accept the flooring material. In other words they will dry out. It is important to note that working time is often affected by the ambient temperature as well as the ambient humidity. For example, in arid parts of the country when the temperature is very high, working times will be much shorter for water-based materials but much longer for moisture-curing materials. Areas of high humidity and high temperature will have longer working times for water-based materials but potentially shorter working times for moisture-curing products. Cold temperatures are going to slow everything down whether the products be water-based or moisture-curing. For reactive adhesives like epoxies or epoxy-modified polyurethanes, temperatures will greatly affect the working time. Reactive adhesives are very sensitive to temperature, so cold conditions will extend the working time and hot conditions will speed things up.

MAPEI's Adesilex P10 Mosaic & Glass Tile mortar mixed with MAPEI's Keraply admixture can be used in submerged applications such as pools, with 21 days of curing time required before filling the pool. Ultraflex LFT Rapid mortar requires three days of curing time before filling the pool. Ultraflex LFT mortar requires 28 days of curing time before filling the pool. And, Kerapoxy CQ mortar requires 14 days of curing time before filling the pool.

Concrete is very good in compression but poor in tension. Reinforcement allows the concrete structure to maintain its compressive integrity while still providing good resistance to tensile or flexural stresses.

MAPEI's Kerapoxy CQ, Ultracolor Plus FA and Ultracolor Plus Max grouts are great choices for pool installations and other submerged applications.

For tile and stone installations, use a MAPEI polymer-modified mortar meeting ANSI A118.4, ANSI A118.11 or ANSI A118.15, or an epoxy mortar meeting ANSI A118.3. For the installation of resilient flooring over Mapelastic AquaDefense, adhere to the adhesive recommendations or limitations for use over nonporous substrates.

Admixtures enable concrete producers and placers to easily mix, place and/or finish the concrete in multiple environments and conditions. Admixtures also provide a way to produce higher-quality concrete without increasing the cementitious content of the concrete mixture, which keeps the cost of the concrete down.

Because you will be directly touching it with an adhesive and flooring material, both of which may not function properly when in contact with a damp substrate. For example, if your goal was to install a solid vinyl sheet flooring over a damp concrete slab using a wet-lay, water-based adhesive, once you covered the adhesive with the sheet vinyl there would be nowhere for the moisture in the adhesive to absorb into; the existing moisture would remain in its liquid state and the installation would be a mess. Another example would be to install prefinished solid wood flooring using a urethane adhesive over a damp concrete slab. The urethane adhesive would cure nicely because it cures by coming into contact with moisture, but the wood flooring would absorb moisture coming from the slab and cup, warp, curl or swell – causing a nightmare of a problem. The bottom line is that there's a reason for the moisture-limits statements of adhesives and flooring materials. As such, the installer should calculate the appropriate measurements for moisture to determine if he can proceed or if he needs to do something more to isolate that moisture from the flooring installation. Learn more here: