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Contractor Tips

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If you are building a house or a commercial space this sheet should be clearly posted and handed out to all your subcontractors. A few simple and obvious precautions will yield a beautiful floor.

General slab requirements for interior and exterior concrete:

  • 4-5 sack mix with a max of 15% fly ash. Absolutely no curing compounds, this will cause your job to be priced as a remodel
  • Machine trowel interior spaces if possible, not too hard, leave some porosity
  • You want the marbling affect from the machine trowel however a burned slab will not take stain well so do not over burnish it!
  • On exterior concrete safety is important, you can make the surface slip resistant by giving the concrete a light broom finish or a rock salt one for more style. (sand can be added to sealer if concrete is slick troweled and slippery)
  • Give the concrete a day to cure before subjecting it to foot traffic

General cautionary statements:

  • Concrete should be protected from pesticides, they can discolor the concrete and alter stain penetration
  • Do not cover concrete for 30 days, any board or object left on a green slab will leave a permanent water mark or stain (all masking tapes should be removed promptly after use, the stick-um can prevent stain penetration)
  • Do not leave wall plates for doors or cased openings for more than a day, this can leave water mark or stains
  • Do not nail support studs into slab, resulting divots can be patched but will not stain the same
  • Do not spill plumbers glue, primer, solder, threading oil, or flux (provide some cardboard or masonite for your plumber and see that he uses it). Threatening charge backs is useful in getting their compliance. Be sure to talk to the plumbers helpers as well, the boss rarely is doing the actual work.
  • Do not use paint, grease pencils, markers, crayons, or red chalk to mark on slab
  • Do not leave metal or nails on slab (will leave rust stains)
  • Do not let contractors eat or drink on slab, greasy foods can really soak in
  • I recommend a trash can in the garage and a job site broom and dustpan to remain on the job. (set a tone of cleanliness and have the slab swept daily)

Timing:

  • For most new construction jobs we like to get started when the space is dried in i.e. chimney capped, plumbing and A/C roof penetrations flashed and roof shingled. Our work begins before insulation if you want scored borders otherwise scoring is done before framing. Staining and sealing are done after drywall and texture and before trim and paint. We then cover the floor after at least one whole day of drying. As part of our service we will wax floor after your cleaning crew has finished their final clean right before move in and apply a final wax finish.
  • For new construction exterior jobs work is best done at the very end of build out. Things like stone work and stucco are hard on the sealer and the concrete can not be covered because of rain. The exterior concrete needs to be protected from painters or the job will be treated and charged as a remodel.

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