Beating the Heat: Summer Concrete Tips for New Orleans

Summer in New Orleans is no joke — and neither is the effect that extreme heat and humidity have on concrete. Whether you're pouring a slab, placing curbs, or doing flatwork, the months of June through September demand a different game plan. Here's what our team at Building Specialties Co. recommends to keep your projects on track when temperatures push past 90°F.

1. Schedule Pours for Early Morning

The single biggest thing you can do is get concrete in the ground before 10 AM. Once ambient temps climb past 90°F and the sun hits the substrate, you're fighting flash set. Target pour start times between 6–8 AM whenever possible. In New Orleans, even early morning temps can be in the high 70s, so don't wait — get moving at first light.

2. Keep Your Materials Cool

Hot aggregates and warm mix water are concrete's enemies in the summer. Ask your ready-mix supplier about chilled water or ice substitution in the mix — most South Louisiana producers offer this. You can also pre-wet aggregates and keep them shaded before the pour. A few degrees off the mix temperature buys you significantly more working time.

3. Prepare Your Substrate and Forms

A sun-baked subbase will suck moisture out of fresh concrete almost immediately. Before the truck arrives, thoroughly wet down the substrate, forms, and any reinforcement. Don't leave standing water — you just want the surface cool and damp so it doesn't act like a sponge when the concrete lands.

4. Watch Your Water-Cement Ratio — Don't Add Water at the Site

When the mix starts to stiffen in the heat, the instinct is to add water to buy more time. Resist it. Adding water at the job site compromises your w/c ratio, weakens the finished slab, and can cause shrinkage cracking. Instead, specify a mix with a retarder admixture to slow set time, or request a higher initial slump at the plant. Talk to your supplier before the pour, not during.

5. Protect the Pour from Direct Sun

Shade structures, tarps, and windbreaks aren't just creature comforts for the crew — they're part of the spec in hot weather. Direct sun on fresh concrete can cause plastic shrinkage cracking within the first hour of placement. Stage your shade setup before the pour begins so there's no scramble after the truck is empty.

6. Start Curing Immediately

In hot weather, curing isn't something you do the next morning — it starts as soon as the surface is finished. Apply a curing compound immediately after final finishing, or use wet burlap covered with polyethylene sheeting to retain moisture. Keep the surface moist for at least 7 days. In Louisiana's summer heat, shortcuts here will show up as cracks and surface dusting down the road.

7. Know the Humidity Factor

New Orleans adds a wrinkle most of the country doesn't deal with: extreme humidity. High relative humidity slows evaporation, which can actually help retain moisture during curing — but it also complicates finishing by extending bleed water timing. Don't rush the finishing process. Let bleed water fully dissipate before troweling or you'll trap it under the surface.

We're Here to Help

At Building Specialties Co., we stock the admixtures, curing compounds, and concrete accessories you need to do the job right — no matter the season. As members of the ACDI cooperative, we also have access to industry resources and best practices that keep our product recommendations current. Swing by or give us a call at 504-895-0322 and our team will help you spec the right materials for your summer pours.