Masonry work in cold weather?

[JoeSpareBedroom]

It's winter in western NY and I never see municipal crews pouring cement sidewalks at this time of year. But my son's working for a mason who uses "products designed to compensate for these temperatures". He wants to take a shot at doing some work on my brick & cement front porch NOW (temps 25 to 40 degrees).

Are these products best reserved for situations where the work MUST be done for some reason, regardless of temperature? My instinct is to wait for the same weather as municipal crews wait for.

I have no specific information about the aforementioned magical products.

[Doug]

Old timers used to use hay to cover freshly poured concrete. I was once at CCNY in the 70's in the winter and they had poured some sidewalks at around 32 F and I saw hay on top of it. It looked funny but I knew the reason for it.

[DD_BobK]

The objective of the "magical products" or cold weather practices is make sure curing takes place before concrete or mortar can freeze.

The good new is.... curing cementitious products produce heat during their chemical curing process (hydration). Often times this is enough. Adding some insulating materials will help as well.

Success all depends on the local conditions & nature of the work.

If your concrete or mortar cure before they freeze...your're golden. But if the mix freezes prior curing ...bummer.

check these out

This Canadian resource provides high quality information on wide range of construction issues. Their stuff is sometimes rather technical but none the less very good and worth the time to read.

I would not risk the potential problems....... I'd wait.

cheers Bob

[DerbyDad03]

Google is our friend:

[jamesgangnc]

Guy I knew added that RV anti-freeze to concrete if if was too cold. Same theory as another poster mentioned, keep it from freezing before it cures.

[The Daring Dufas]

I'd ask a Russian how they pour concrete in Siberia. ^_^

TDD

[Doug]

That's a neat idea if it works.

[EXT]

Easier to ask a Canadian contractor. They build all through the winter.

[The Daring Dufas]

Dang! I forgot about my Canuck pals, they easier to understand when they talk, er, mostly. ^_^

TDD

[Tegger]

"EXT" wrote in news:4f554d99$0$2614$ [e-mail]: .

Yep. I see them pouring foundations at +10F. They do actually mix antifreeze in with the concrete. I'm assured it has no effect at all on durability of the finished product.

They even brick and spackle at +10F as well. They rig up giant tarps all around the building, then they run heaters inside the resulting enclosure. Apparently this is not for the mortar (which has antifreeze), but for the bricklayers' comfort.

Roofers seem to get the short end of the stick. They're up there on New Year's Day, sometimes. No tarps, no heaters, no comfort for them!

[DerbyDad03]

I had heard of using antifreeze also, but some of the things I've read specifically warn against it.

"Automotive antifreeze should not be permitted in mortar. The quantities of ethylene glycol needed to significantly reduce the freezing point of mortar can deteriorate the calcium compounds in Portland cement and hydrated lime."

The admixtures that are "permitted" don't lower the freezing point of the mortar, they accelerate the cure so that the time needed to protect the mortar from freezing is shortened.

[tmurpha1hi]

All additives used for mortar and concrete for freezing protection weaken the product. It is a question of how much of a hurry are you in. If it is going down to 25f you should wait if you can. Spring is just around the corner.

[Doug]

Around where I live the roofers won't roof during the freezing temps in case of ice. We don't get much ice tho where I live.

[JoeSpareBedroom]

Thanks to everyone for the information. We're about to have 4 days of 60F /

50F / 40F etc. My son stopped by with his boss, who checked to make sure the plan was a good one. I asked "how much"? His boss said "Beats me. Your son says your birthday's coming up next week. Ask him!"

Just got a text message from my son: "Boss paying me to make form for repairing your concrete! He likes birthdays."

Try not to think about the massive seafood dinner the kid's going to get later this week. :-)