For concrete and flatwork contractors
Pour on the day the slab will hold.
Pour, finish, protect and seal checked hour by hour for each jobsite, with odds from up to 146 forecast runs, not one forecast's yes or no.
The costly call
A bad pour gets ground out on your dime
A flatwork pour that cracks, dusts or freezes gets ground out and re-poured on your dime, and a pushed pour still costs a short load and a crew day. A green light for tomorrow morning says nothing about the 40 °F night two days later.
How it works
From your place to an answer
Add the jobsite
Drop a pin on the drive, patio, slab or footing. Any jobsite in the US.
Set how you pour
Your pour start, your protection period and whether you run a hot-weather plan. Every limit is yours to change.
Pick the day
See which day the pour and its protection hold, how sure that is, and the hour evaporation peaks.
In the app
See it on a real forecast
Real forecasts for Atlanta, North Georgia, captured October 5, 2026. Yours will be for your own place and limits.
What you get
Built for concrete and flatwork contractors
Pour-day scorecard
The next 7 days, each judged on the pour plus its protection period, with the odds it holds and the hour evaporation peaks.
Protection period
Cold hours in the 48–72 h after you place, the chance of a freeze in the first 24 h, and blanket hours for a heated mix.
Evaporation watch
Hours above 0.20 lb/ft²/hr each day and the hour evaporation peaks, so you know when plastic shrinkage cracks are coming.
Finishing window
Four-hour stretches under 0.15 to bull float and broom before the bleed water is gone.
Stamped & decorative check
A 0.10 evaporation cap for low-bleed mixes, colour and stamp held between 50 and 85 °F, and dry for 12 hours after.
Wall & footing 120 h cure
Formed pours with a 120-hour check that tells you when the footing needs heat or blankets.
The pour steps it times
Flatwork pour (slab, drive, walk)
Place, finish and get it under protection: no rain on the pour, no washout in the 8 h after, evaporation under the cap while you finish, and air at 40 °F or above through the protection period. Protection period 48 h.
6-hour window
Wall & footing pour
Formed concrete: the forms hold the moisture, the cold is the risk. A failing hour in the 120 h cure means heat or blankets are needed, not that you cannot pour.
8-hour window
Exterior finishing window
The hours you can bull float and broom before the surface dries out ahead of you and bleed water is gone.
4-hour window
Stamped & decorative pour
Colour, stamp or exposed aggregate, where a short finishing window ruins the look. Protection period 48 h.
6-hour window
Curing compound or sealer day
Spray cure or roll sealer on a dry surface that stays above the product's minimum; your product's data sheet wins. Michigan Concrete Association advises not sealing freshly placed concrete going into freeze–thaw: seal after the cure.
4-hour window · daylight only
Tear-out & base prep
Break out, haul off, grade and compact base, set forms. Frozen ground uses soil temperature at 2.4 in from the main forecast only, with no odds.
9-hour window
What else it watches
- Pour-day scorecard
- Protection period
- Evaporation watch
- Rain on the jobsite, last 7 days
- Freeze on fresh concrete
- Heat on the finishing crew
Every answer counts the forecast runs that keep the whole pour step inside your limits, at your jobsite.
Founding members
Join the beta — your first six months free
Only 10 founding places: the first 10 concrete and flatwork contractors to apply get the Concrete & Flatwork edition free for six months when it launches. No card needed. When they're gone, it's the waitlist.
Only 10 founding places.
- Your first six months of the Concrete & Flatwork edition free when it launches
- Early access to the app as it is today
- A say in which pour steps the Concrete & Flatwork edition times next
Questions
Asked before you start
How is this different from a weather app?
A weather app shows one forecast. This runs your pour, finish and protection period through each of up to 146 forecast runs and tells you how many hold.
I already use a free pour app. Why this?
A yes / no for the morning is one forecast. This gives the odds across runs, checks every hour of your protection period and shows when evaporation peaks, so you can pick the day, not just test it.
Can I keep a record of my calls?
Yes. Log a pour decision and the decision log keeps the odds, the forecast evaporation and cold hours and your note for that jobsite. Export it to CSV. It records what the forecast showed, not site readings.
Does it know my concrete temperature?
No. It assumes concrete at air temperature, or at the minimum you set for heated mixes.
What data does it use?
Forecasts for your jobsite's grid cell: an hourly forecast plus up to 146 forecast runs from three independent forecast systems, pooled and judged run by run, 14 days ahead.
Where do the limits come from?
Each one names its source (ACI 305R and 306 via published summaries, CDOT specs); the rest say "starting point" and are yours.