Here in Los Angeles, California, resurfacing floors with concrete overlay can be quite a challenge. Sure, we don’t get the harsh climate temperature drops and the piles of snow they get on the East Coast.
But we do get hot, dry, windy days with temperatures of over 100 degrees. Such conditions are equally undesirable when working with concrete overlay (or any cement-based material like regular concrete, stamped concrete, etc.), as they can result to outcomes such as plastic shrinkage cracking or chemical drying shrinkage.
Tips and Tricks on How to Do It
Thankfully, there are tips and tricks on how to handle such weather conditions and that’s exactly what we plan to share with you in this post. Obviously, this information could be useful for contractors, but we thought it can be quite helpful for consumers as well. If you’re hiring a contractor to work on your concrete this summer, it’s good to be able to make sure they have a coherent plan on how to handle the LA climate.
Let’s jump right in.
1. Mix Retarders with The Concrete Overlay
Once the concrete overlay gets applied, the water that was previously mixed with it begins to evaporate. When it evaporates too quickly, it can create plastic shrinkage cracking. Same applies to pouring regular concrete, and even concrete stamping. Retarders are admixtures that slow down the evaporation process. They are a must for hot, dry, windy climates such as the one we have here in Los Angeles.
2. Apply The Overlay (and The Sealer) in The Coldest Possible Points of The Day (or at Night)
This one is pretty self-explanatory. Unfortunately, when it comes to decorative concrete, you can’t start working right after sunrise. You have to wait until the morning dew has dried up, which normally happens between 8AM and 9AM. Unless there’s a heatwave, you’re going to get a milder temperature until about 11AM, which gives you enough working time to coat most projects less than 2,000 sq. ft. After this window, your second best bet is to start a little before the sun sets (around 6:00 – 6:30PM).
If you’re worried the sun will set before you can finish, get yourself some high wattage LED lights from Home Depot. They’re usually bright enough to do the trick.
3. Mix the Overlay with Cool Water
Not much to expand on here, just make sure the water isn’t too cold.
4. Place Your Mix In The Shade
This is common sense. When you mix your bucket of overlay, make sure not to leave it in direct sunlight. It’s better to have to carry it a few feet every time you need to pour some down than to be rushed while applying.
5. Avoid Leaving Masking Tape Overnight if You Can
Masking is really time-consuming as it is. Try not to create even more work for yourself by leaving it overnight (or for several days). If left on for too long, the masking tape is bound to either rip in very small pieces while pulling it off, to leave a hard-to-remove residue after it’s been peeled off (or both). We try to avoid all of these as best as we can.
6. Get a Tent for Shade
You can get a 20’ x 10’ tent for about $150 in Home Depot. It gets pretty windy here (especially around the beach) so we usually have to weigh our tent/s down to prevent them from flying away. Wrapping plastic around the poles of the tent may serve as a good windbreak that will increase drying time, which will increase the time you have to work the overlay.
7. Spray the Sealer Instead of Rolling It
Rolling the sealer with a foam roller is an often preferred method of applying the final protective coating by many contractors. When it’s too hot out, however, the roller may lift little strings of sealer only after the second or third time it goes over a certain area. This can ruin all of the hard work you’ve put prior to sealing by leaving ugly spots throughout the surface. Apply the sealer with a pump sprayer, instead.
This method of application will definitely increase your cost (you can only spray sealer once with every pump sprayer because it gets clogged up), but it will save you a ton of stress and frustration. An evenly sprayed coat of sealer tends to be heavier than a rolled one too, which only gives better protection and fewer callbacks.
Working with any cementitious materials (or sealers) in a hot, dry, windy climate is not easy. Thankfully, through proper planning, you can make sure the climate doesn’t negatively affect your project.