Replies

1. 
   Johnnie_Browne | Nov 19, 2000 05:50pm | #1

   *
   the way we always did it was: order a pea gravel mix (usually a 3000lb mix with pea gravel instead of large aggregate) pour a normal slab and right when it get to the point that you can walk on it. wash with high pressure water hose to exposed the aggregate.

1. 
   teo_ | Nov 19, 2000 08:20pm | #2

   *There are times when you do it yourself, and times when you call in the pros. Concrete at the entry is NOT the time to practice a new skill. Do all the heavy work and call around until you find someone who'll come in at the end and do the finish work. It'll be well worth the price.

1. 
   FredB | Nov 19, 2000 08:22pm | #3

   *Well I'm not really a concrete guy, but I can tell you how a sub does it for me. He orders with the size aggregate the customer desires. Then just before the final finish he seeds the surface with more of the same size aggregate. Then the final wash with a hose and it looks great.

1. 
   G.LaLonde | Nov 19, 2000 11:37pm | #4

   *One advantage to seeding it on top after driving down the mix aggregate, is that you can use many unique and somewhat expensive kinds of stone without mixing it throughout the whole mix. You also get better control of your surface appearance.

1. 
   Ian.D.Gilham. | Nov 20, 2000 02:52am | #5

   *The disadvantage of adding aggregate to the top of the mix and trowelling in is that you get a lean mix on the wear surface, which isn't a good idea. Johnnie Browne has the better solution, but I would add use a stiff mix and don't finish with a steel float or you'll bring all the fines to the surface which won't look good when you wash it off.

2. 
   Norman_Williams | Nov 21, 2000 02:17pm | #6

   *We have always used a retarder on the surface. The material is sprayed on top of the finished concrete. Cover with poly. Come back the next morning and rinse.

3. 
   Mike_Smith | Nov 21, 2000 03:17pm | #7

   *we broadcast the aggregate to the top.. and we use a retarder like norman...masonry/concrete supply yards sell retarder....

4. 
   Dave_Richeson | Nov 23, 2000 07:24am | #8

   *Use the retarder and wash the fines off gently. To much pressure will lossen the dense aggregate in the ware layer. Better yet call a pro. He will have to fix it if he screws it.

5. 
   Tim_McGuire | Nov 28, 2000 05:51am | #9

   *Gene, Try putting a small box of brown sugar in a garden sprayer, add water to fill. Shake well. Spray onto the surface after floating and edging. Let it set until you can't push your finger any deeper then a 1/4" into the concrete. Wash off with water. To help speed up the wash time use a soft bristle broom and scrub the surface lightly. Keep rinsing till no more concrete washes off. Should get a great looking surface.

6. 
   Tim_McGuire | Nov 28, 2000 05:53am | #10

   *Brown sugar does the same as retarder, but is alot cheaper. good luck

7. 
   K_Johnston | Nov 29, 2000 12:32pm | #11

   *I have heard that gypsum is also a retarder. Is this true?

8. 
   Dan_Fox | Dec 14, 2000 08:06pm | #12

   *Any Sugar will do the same thing as fancy retarder it is mostly just colored sugar water , I seen guys use Peps ( not diet) . I use a 6sack pea gravel mix and seed after the 1st float , float the seed in till covered and leave alone , don't tamp or over float or you will end up with a sand finish , after set enough for steel float finish like a broom finish sugar the surface after steel float and leave till slab is set the top will not go off and can be washed off without loosing your rock.

2. 
   GeneDavis | Dec 14, 2000 08:06pm | #13

   *
   We want to do some slabs on grade at the entrance and driveway apron and stoops at a new construction project. Does anyone recall any books or articles that discuss and show technique? Is the regular slab poured, screeded, and then is the decorative pea gravel scattered over the surface and troweled in? Timing of the wash-off with water spray? I seem to recall seeing this done by a flatwork contractor on one of those Hometime or This Old House shows.