It is 110 degrees here during the day now and will be like that until September. I want to do a lot of concrete work and was wondering if I should wait until winter. I think I read somwhere concrete cures too fast when it is hot.
I need to add some driveways and a patio, but it can wait until it cools off if it will be stronger.
Should I wait until winter?

 

You'll get a lot better quality job in the winter time.

 

Thats what I thought, and I am not in a hurry so I will wait.

 

I am sure your local suppliers can have the mud on the job in the wee hours of the morning so it can be placed prior to the heat. There is also a wide range of retarders available to help out. Up the % of flyash give a guy a little help in the heat as well. If you need to get it done with the heat there is always a way!

 

Yeah, but I don't "need" it right now so I am willing to wait if it will affect the finish or quality in the long run.

 

Judging from Mudmaker's username, I'm sure he has a lot more knowledge of batching concrete for specific applications than I do, and I know that concrete placement goes on during the hottest parts of the year in the desert. I'm a masonry contractor, so I'm coming from that angle. It's a lot easier for me to do a good job for a customer when it's cooler out. I don't know how those guys can stand doing it in the real hot weather, but they do.

 

mine is being poured at 0600 tomorrow morning, our highs are 100 in the afternoon here. you just have to keep it cool for a couple days so it don't crack.

 

Frequently larger pours are done at night in Arizona and desert locations. As said there are a large array of retarders that allow for pouring in hot temps.

We do stamp work and keeping the concrete at the optimal stamping constistancy is critical in high temps. We use a number of diferent retarding agents and add mixtures as well as iceing some loads in order to get the results we want when the temps go up. Can't stop work just because it's hot out. Most of what we use was designed with pouring in desert conditions in mind.

We had a batch that got screwed up by the mix plant. They loaded the batch with so much retarder that we literally poured on monday and dug the batch out with shovels on thursday after we determined why it wasn't setting right. Batch plant said they mixed for a bridge job before ours and accidenally doubled the retarder and dumped it in our batch. The intent was to pour in the heat of the day on the bridge and still be able to finish the concrete the next day. Definately worked.

If you can afford to wait til the temps are cooler I'd do it. If not don't worry much unless you plan to do all the work yourself. Remember it's not just the heat, it's the humidity. The very dry air will suck the moisture out of the concrete even in moderate temps out there. Proper mixes and damp curing will help to combat this.

 

Most of the work I've seen out here does not appear to been done by a mason. More like day laborers who are unskilled but used to this kind of weather.

 

That is the easiest way to deal with the hot days IMO. I am no long in the ready mix business as I just sold out, but many time during July and August on large slabs we started at 10pm and had all the mud delivered by 5am. Much easier to get it done at night. Traffic is lighter, trucks run better, mud stays cooler. On smaller pours it was pretty normal to have mud to the contractors by 4am.

Like DSW said, you dont stop pouring concrete due to high temps. You just learn how to work with it. Either by admixes, schedule or often times both. Professional concrete contractors know how to deal with all types of weather associated with pours. I watched a crew save 30,000 sf of parking lot after a fluke thunderstorm made it look like exposed aggregate. The key was they knew there stuff and how to deal with issues as they where thrown at them.

 

Opps. Just noticed that my first post did go thru when the computer lost the cable connection in the middle of posting. Sorry for the double. I retyped the second thinking the first didn't post.

 

Got it-

 

On the highway here when they are patching they are doing the work at night. Less traffic and the stuff is ready to be driven on in the morning.