is it ok to pour concrete (only ~3" thick) in drizzly/rainy weather?

patandchickens

Flock Mistress
12 Years
Apr 20, 2007
12,520
476
341
Ontario, Canada
Sorry, this is not coop related (but it could apply to things done around the coop too, I imagine, so there!), but I've gotten some pretty good concrete-work advice here in the past and am hoping the relevant people might be around today too
smile.png


I've put pavers on a sort of patio behind the house, but because there are round sonotube post footings sticking up (for soon-to-be deck over part of it) and other irregularities, plus I ran outta pavers <g>, there are irregular shaped gaps that I want to pour 2-3" of concrete into. Most are between the size of my palm and the size of a bed pillow. This will be poured (well, trowelled) onto a bed of screenings over 6mil plastic, if that matters.

If I put plastic over the stuff as soon as it has started to cure on the surface, can I do it today, when it is generally drizzly and tomorrow night it is supposed to start with light rain lasting off and on for the next week+? Or will it end up too crumbly? (If I don't do it today, I am afraid of being forced into either doing it in even wetter weather, or doing it when the temperature is freezier than it ought to be -- I can put bales of shavings on the areas for a couple weeks but there is a limit to how much good that will do if the weather returns to more seasonal temps than we're having now... but, it is not impossible that we might get a warm dry period again, I just dunno)

Thanks for any suggestions/advice,

Pat
 
I think it would be fine if you could really judge well the amount of rain you will get, when I pour fresh concrete I always spray a fine mist on it several times so it will cure slowly making a stronger set. If you mix it a tad dry and still trowelable all you will need is about 3 hrs to cure @ 3" before nothing can hurt it, I think you will be Ok.

AL
 
I agree with AL. If it doesn't rain hard enough to wash out the concrete until it sets, it should be OK. Generally it will set in a few hours and should be rather impervious after that, especially since you are pouring small sections. Good luck.
 
Obviousy since it raining it is above freezing. My DH suggests waiting til spring when it is warmer. He does not like to pour concrete below 50 degrees F (10 C). You need to also consider the ground temperature. Today our air temp is 37F(about 4C) and our ground temp is 25F (about -4C). With the freezing and thawing that takes place in cold climates I would be concerned also about pouring concrete without using rebar or iron mesh of some kind to hold it together. Can you just get some more pavers and call it good until spring?
 
Yeah but it is such a small area and small batches rebar is a non issue, Concrete creates heat as it cures so temps at this point are still a non issue. plus we are only talking about a couple of hours at most. Might I suggest adding a flexible pourable/mixable adhesive to your slurry to encourage bonding although it is not essential or required. I only pour and set about 20,000 yds a yr so I know just a little about concrete, Construction co owner.

AL
 
Thanks everyone! I knew I could count on you
smile.png


Ground is not frozen yet, I would guess from behavior of frost and such that it is probably around 35-40 F on the soil surface, a little warmer with plastic on it, so I think I am good in that regard. (That's exactly why I am leery of waiting til this rainy spell ends, though -- by then, normal Nov weather will probably have returned and the ground *will* be freezing each night)

Birdbrain, this is not a slab I'll be doing, it is just spots here and there; I really do want it covered before winter though b/c it is in an area where we always have a lot of water-into-foundation issues and I want the whole thing covered (on top of the underlying plastic sheet) to help deflect rain and snowmelt. I spent a whole lot of time grading this area by hand, and ensuring the plastic and screenings and pavers went on in a fairly unbroken kind of way, I do not need some kid or husband with a snowshovel accidentally punching holes in it LOL

If you mix it a tad dry and still trowelable all you will need is about 3 hrs to cure @ 3" before nothing can hurt it, I think you will be Ok.

OK Al, I'm going ahead and doing it -- you are probably right about using a bottle of bonding agent too, but I think I will skip it since it would require a separate trip to the store to get some (just got HOME from hardware store getting other things for other work
tongue.png
) and honestly I think these patches are likely to separate at the seams no matter what I do, the way the ground flexes as it heaves in late winter. There's sand-filled cracks between the pavers anyhow, so, whats a few more cracks
tongue.png


Appreciate the advice!
smile.png
Thanks again,

Pat​
 
I've done lots of concrete work in drizzly rainy weather. If you don't care what the finish is like, not a problem--much better than hot weather! Sounds like you've already done the work, but if not, just cover it with tarps or plastic when you finish. I also keep the wheelbarrow that I mix in tarped, so the concrete doesn't get soupy.
 
I did most of it (2 sacks of mix) last night, chiefly in the dark
tongue.png
- will finish this afternoon, hopefully *not* in the dark. Looks quite adequate, hopefully will hold up equally adequately. There was no rain on the weather radar when I finished so I did not plastic-cover it, and indeed it has not rained yet, but this afternoon's bit will probably need covering.

Thanks everyone!
smile.png


Pat, who generally enjoys playing with smallish quantities of concrete, except I *loathe* mixing it up, even in that roll-y barrel-shaped thing I got a couple months ago to do 14 sacks' worth of post footing with.
 
Would cover with plastic, and then if you think it can get reallly cold, add straw, leaves, compost, dirt, whatever to depth of 8" or so to be sure it doesn't freeze. Otherwise you could have spalling. Best that it not freeze until it is no longer green. Ambient temp is a big factor in rate of cure.
 

New posts New threads Active threads

Back
Top Bottom