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[Gene GeRue <genegerue AT ruralize.com>]

This is a wonderful post and I thank Rob for having saved it and now 
putting it out for us. Very few details I would add. An alternative to 
rebar today is chopped fiberglass. Just buy it by the bag and mix according 
to directions. If you order from a concrete plant check the cost and make 
the decision when you order. Make sure you have more help than you think 
you will need. I have been put in the position of having to finish a large 
slab with only an inexperienced and clumsy helper and I damn near killed 
myself. That total lack or respect cost the friend any further offer of 
help by me.

> ForestHaven wrote:
>
>  > Thanks, Tvo.  My thinking's much clearer on this project, now.
>
>  >>>tvoivozhd---well, I always feel that I have forgotten something
> important, and usually have.  So here's some parting admonitions:.
>
> a.  Drive the job, don't let it drive you.  By that I mean plain
> concrete sets rapidly.  You have a very limited time to place, screed
> and finish it.  It also must be very well mixed, but not longer than
> necessary.  The minute you mix water and Portland, the crystalline
> structure starts to form.  Prolonged mixing destroys its formation and
> weakens the end product.  Have on hand and employ the proper tools,
> equipment and supplies.
>
> b.  Work with the weather, not against it.  Don't pour concrete when it
> will be exposed to rain before setting.  Equally important, a 100
> degree, sunny day, with a strong wind can turn an easily managed job
> into an unmanageable disaster---setting up before it is properly placed,
> before voids can be vibrated out, and before it can be screeded flat,
> much less floated and finished.
> c
> .  If you must work against the weather, minimize the obvious problems,
> i.e., put retarder in the mix if it is hot and windy, accellerator in
> the mix if it is cold, or rain threatens.
>
> d.  Protect the concrete during the curing process---keep the surface
> damp.  It helps to cover it so sun and wind don't dry out the surface.
> In extremely hot, dry, windy weather, spray it frequently. And protect a
> slab against rain with a cover that won't blow away too.
>
> e.  Unless you use a plasticizer, you should vibrate any deep sections
> to remove voids. Don't overdo it though, prolonged vibration will cause
> the concrete mix to separate and stratify---creating a weak point.
>
> f.  Similarly, when finishing, you have to float the slab---generally
> with a big four-foot bull float on the end of a six-foot handle.  You
> want to smooth it, but not bring up too much paste to the surface where
> it will constantly be powdering off when cured.  It takes judgment as to
> when to start floating---the concrete should be setting, but not to the
> degree you can't work it.  A big engine-powered rotary trowel when they
> were first introduced, was the best investment I ever made---made
> precise timing unnecessary.  You could beat down, make a level and
> beautiful finish on a slab that was long beyond any control with manual
> floating and trowelling.
> You may have to walk on the slab when finishing it.  Large enough pieces
> of wide board or plywood make it possible without impairing the finish.
>
> g.  Like painting, preparation makes a hard job easy, or an easy job
> impossible.  Use a transit if you have one, a water level or carpenter's
> level to level your formwork and grade-stakes, if any (pull the latter
> when you have screeded to their tops, and work out the voids)  Always
> have two level formboards across which you can saw your two by four or
> two by six screed.  In a wide slab, or one in which you are pouring
> close to walls, put in a temporary third board so you have two boards
> for screedwork.  Pull the temporary board out to finish the slab
>
> Use an adequate type and amount of steel---placed and tied properly as
> described in most concrete books.  You can pull up road mesh with a hook
> after pouring concrete, but it is easier to place steel on bridges which
> are left in after the pour---it is the only way you can be sure the
> steel is adequately encased by concrete, and near lower (and sometimes
> upper) surfaces where the tensile strength of steel should be
> focussed---in the middle of the slab it will hold it together, but be
> otherwise useless, causing unnecessary cracks and lowered resistance to
> loads..
>
> h.  Where do you want your water to go?  On the interior of a house this
> applies primarily to kitchen and bath and expected spills, leaks and
> overflows.  You don't want a leaky pipe draining into the family room,
> particularly if the floor cover is susceptible to water damage.  So,
> while most slabs should be dead level, sometimes you have to create a
> grade to a drain.  My idea of a simple, easy to care for house is one
> you can hose down.  In a warm climate and a house with stone, brick or
> CEB walls I wouldn't even put in interior drain plumbing for that
> purpose, I would slightly slope the slab to a series of perimeter drains
> which would of course be screened---and obtain the additional benefit of
> bringing outside air at ground level where it is coolest (through grass
> shaded by shrubbery)..
>
> i.  Improve your understanding beforehand.  There are innumerable books
> on concrete and masonry.  I have quite a few I bought in used bookstores
> and library sales for twenty five cents each.  For beginners, the books
> with a lot of illustrations on all phases and many different
> applications of mason's work, are the most helpful. Your local library
> will have or can get on interlibrary loan most all the books you will
> really need.  If you want to buy some, the best places are used
> bookstores and library sales, and for new ones, your local
> building-supply stores. In the last, among others,  you will find the
> "Sunset" series, including the "Garden and Patio Building Book"
>
> The "Masonry" book of the Time-Life series appears from time to time in
> used bookstores.  A couple of very small books you might run across are
> "How to Work with Concrete and Masonry" by Darrell Huff,
> SBN 06-463354-3,  "Concrete and Masonry" by Richard Day (Fawcett
> Publications).
>
> Old standbys are "Basic Construction Techniques For Houses And Small
> Buildings Simply Explained", prepared by the U.S. Navy (published by
> Dover), ISBN0-486-20242-9, and from TAB Books, "Concrete & Masonry",
> ISBN 0-8306-5902-1
>
> Your librarian can obtain the two above, and another useful, newer book,
> "The Visual Handbook of Building and Remodeling", by Charlie Wing
> (Rodale Press), ISBN 0-87857-901-X
>
>
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