?Wintertime Construction?

[Bryon Stewart]

I would like to get some comments on problems constructing a home in the
winter, especialy related to concrete and mortar.

The house will be built in Northern Virginia this winter were the temps
will be below freezing at night about half the time and an occasional
snow storm. It will have a poured concrete basement and brick siding.
The sheething will be weather coated OSB with Tyvec house wrap. The
excavation will start sometime in January and the project is suppose to
be finished in five months. As the homeowner I would like to know some
things to watch out for, to make sure the proper practices are followed
for wintertime construction. Any info would be greatly appreciated.

[prlau...@my-dejanews.com]

In article <3677E4...@erols.com>,

When we are doing winter work on Corps jobs we maintain concrete and mortar
above 50 degrees for 3 days and above freezing for 7 days. We do this by
building tents of cure blankets and reinforced visqueen and heat them with
forced air propane heaters. Since the R value of our tents is so low we use
a lot of fuel. We also must be very wary of fire i.e. igniting the tent
and/or form material with the heaters. In our experience, the second night
is the most critical; by then the concrete isn't generating very much heat
and isn't past the point of freezing yet. Sometimes we are required to use
recording thermometers inside our tents to "prove" the concrete has been
maintained above the minimum temperatures. When we are left to do our own
quality control we maintain the concrete above freezing for 3 days and then
remove the tent and the forms; generally we cover the concrete with cure
blankets without heat for a couple more days. On concrete walls we use the
kickers and forms and scaffolding for framework to drape the tent over. On
masonary walls we use the mason's scaffolding as the frame for the tent. The
area we work, is Montana. We have poured good concrete in below zero weather
as evidenced by the test cylinders left under the tent with our concrete.
Sometimes, working and pouring and tenting concrete in those conditions isn't
much fun. Reliable power is a must; if the power fails in the middle of the
night then...... Reliable 500,000 btu heaters are also prized. Good concrete
and good hammers "ring" when you give it the simple test of a whack or two.
Edges, like corners that are crumbly are a tell-tale and so is soft mortar
that is a few days old. I've made a good living in construction, mainly
because we pour concrete year around. Good luch with yours.

ron

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[John & Beth Cappiali]

The first thing, the concrete and mortar can't be done under 30 degrees of
air temperature. Ice crystals will form. The concrete is going to generate
a certain amount of heat as it cures. This is part of the chemical reaction
to the concrete hardening. This heat needs to be kept in with concrete
blankets hung over the outside each night that work is done and the blankets
should be left on the completed work for at least two days. Even ask our
mason to use a cold weather additive such as "liquid heat" . Any mason
supply house carries it. Its a liquid your mason adds to the water as he
mixes his mortar. Mortar needs to be mixed for brick work in small
amounts. Warm water mixes better and sets faster. If he uses a pair of
fifty five gallon drums set up on a few blocks of concrete, he can use a
propane roof gun set on medium with a hundred pound tank of propane to keep
the water warm. It'll be easier for him to work with. The cost involved is
the propane. A hundred pound tank costs maybe $100, you could run it for a
week solid, 8 hours a day. The torches themselves, sell new for $125 at any
roofing supply company or Home Depot. Landscape supply houses sell them as
weed burners. Of course do this outdoors. (Don't laugh) Every week you see
some genius in the paper trying to burn the paint off the woodwork with a
gas torch instead of and electric heat gun.

Any more questions?

[David Harms]

Where do you get your propane? We just had 10 100# cylinders delivered to
the job site. Invoice total $227.95
John & Beth Cappiali wrote in message <368EDE34...@erols.com>...

[Steen Holmquist]

Its all good help and advises, but i have a alternativ or suplement for it.
In my countri we somethime uses hot water and blowtorth too. But furthermore
we somthime add mortar alkohol. Its here exctential that its applyed in the
right amount. For 100 Ltr. mortar add at least 1 Ltr alkohol and most 4 Ltr.

steen.h...@optiroc.dk

[Jim Ilkay]

I used to build in Toronto, Canada, year round and we used straw
extensively. Right after excavation we'd lay down about 12" of straw in the
areas where the footings go and replace the straw after the pour. You'd
occasionally replace the straw if you had a lot of wet snow or rain but I
remember coming to the job on 30 below days and pulling back that straw and
seeing puddles of water on the ground. It's amazing how well it worked and
it was way cheap also. Once we got the sub-floor on we'd light a salamander
and keep it on low but I'd still keep straw on the outside until the
backfill was done.

Jim Ilkay
bui...@texas.net