How to prepare concrete for staining

How to prepare concrete for staining

Introduction

The finished outcome of a concrete stained floor or concrete overlay floor is directly the result of the care and responsibility taken by the builder and subcontractor that work on the slab before the arrival of the concrete straining crews. As the staining crews cannot be onsite to ensure the care of the concrete floor it should be covered during the entire construction process.

It’s recommended that the slab not be covered with plastic after the pour is made as this will leave some very interesting marks on the slab that are not very appealing for most that buy the staining.

Masonite or plywood can be used until the slab is “dried in” and then two layers of roofing (heavy gauge rosin paper) paper can be used for the duration of the construction process provided that the subcontractors are all informed not to spill adhesives, paints, solvents, oils, varnishes or stains on the slab. That being said, it’s best to cover the floor thoroughly yourself as it’s truly important to only you.

New construction instructions for the concrete to be poured

A quality batch of concrete should consist of at least a 5 sack mix with no fly ash, retarders, or chloride accelerators. The slab should be lightly power troweled to give a slick finish without creating too many “burns” on the concrete surface.

This will give you a beautiful look and at the same time ensure that the concrete is readily stainable. The concrete should be wet cured using curing blankets for at least 7 days while keeping the concrete at all times wet during those 7 days.

No curing compounds are to be used. The use of curing compounds will result in a slab that is either impossible or very difficult to stain and will be a very large additional cost to remove.

The paper should be taped together and the tape should not be applied to the concrete floor for any reason. This will act as a barrier (stain-resist) to the stain when applied.

The mistaken spilling of the contaminants will just add to the cost of the staining process because these are very hard if not impossible to remove and are not very attractive if exposed during the staining process.

The concrete floors are to be clean swept and removed of all building materials, furniture, equipment, and fixtures, and the paper covering the floor. It will cost you more if the people responsible for doing the staining start to clean and move obstacles.

Preparation has a direct effect on the outcome

If the above-listed procedures do not adhere to the stains, chips in the concrete floor and imperfections will all be readily apparent but fear not sometimes but not always these all add character to the slab and of course, we are after an aged mottled “old world” look so this may just add to the character.

That being said the owners, builders, and subcontractors are solely responsible for the condition of the concrete floor prior to stainers commencing work. They are not responsible for the condition of the floor before that and won’t take any.

Usually, when you contact the staining contractors they will insist that the floor is ready for their work. They might want you to instruct the other contractors on how to prepare for the job.

In that case, they should give you instructions to be given to the general contractors and all the subs and make them sign off on having received them. That way when you back charge them for possible additional charges from the floor stainers and the other contractors can’t deny responsibility.

The use of plastics and tapes can harm the walls and paint

Extended-release tapes and plastics are usually used to mask the baseboards and the walls. Some concrete strainers don’t accept responsibility for paint peel off during the removal of the plastic and tape at the end of the process.

Staining is an extremely wet process and as such water and stained water can make their way under the tape and onto baseboards and trim. Builder’s grade paint is very often what would be considered below grade and often does not stand up to these conditions.

Prepping a concrete floor properly is key to success

All the resists must be taken care off

Anything that will not allow the stain to come in contact with the concrete surface is what we refer to as a “resist”. All glues, adhesives, pipe dope, sealers including curing agents, etc. fall into this category.

For instance, your painter has taped his plastic or drop cloth to the floor and when pulls up the tape it leaves behind an adhesive residue, It’s important enough to repeat this here. This will cause the stain to show the tape spot on the floor and take the stain differently in that area.

If your plumber puts in a sprinkler system or regular plumbing and drips pipe dope on the floor you will see those spots as well. If the painter doesn’t cover the floor well and the overspray of the paint gets on the floor it may show as well even though it appears all the paint has been removed.

How to protect the wall with paper and cardboard

If you are going to cover your floors with paper make sure to use at least builder’s grade paper and at best rosin paper that can be found in the roofing dept. Tape the paper to itself and not to the floor (repeating again).

Overlap the paper approximately 4 inches and that should give you good coverage. Most large rolls of paper come with about 432 sq. ft. of coverage with overlap you can figure around 350-375 sq. ft. coverage per roll.

I would also recommend you place cardboard or Masonite on top of the paper. Do not use plastic as this will not let the concrete “breath”. It will trap the moisture in and it will need to dry longer to be stained then.

If you want a beautiful concrete floor this is a small expense to consider when you live with these beautiful floors for at least a few years. Take the time to do this step and it will pay dividends beyond the small amount of time and money it takes to do it.

Mistakes to avoid

These are a few contractor mistakes that cannot be remedied in most cases so be sure to make all of your contractors are aware of these conditions.

  • Contractors normally use Sharpies or Marks-a-Lot permanent ink markers.
  • Electricians normally use spray paint to mark areas where outlets will go-this paint does not come off easily or sometimes at all.
  • Sheetrock and drywall contractor are notorious for making the biggest mess and for some unknown reason they expect everyone else to clean up after them.
  • Painters are kind of like drywallers they spray their paint pretty much wherever they want and when they roll they’re not much better, you need to tell them to cover the floor or they won’t. If they are spraying the cabinets with urethane or varnish it will get on the floor also.
  • Carpenters like to use red caulk for their caulk lines- ask them to use orange.
  • Plumbers that are installing a sprinkler system in commercial spaces will use oil to cut the pipes and when they install them they drip that oily water on the concrete which will leave a stain, they’ll tell you it won’t but still it will. Also, the pipe solvent they use is clear and won’t show until the floor is stained and then there is nothing that can be done about it.
  • Concrete contractors use curing agents on the concrete to hold in moisture during the hydration process(curing process) these curing agents block the stain’s penetration into the concrete. Wet cure, don’t use curing agents.
  • Remodeling projects. Many folks want to rip up their carpets and tile and linoleum and think they can just stain the concrete. It’s just not that easy. Under your carpet, tile, or whatever are a bunch of potential problems that just might not let you stain the concrete. This is sometimes when an overlay might be the answer to the question.

After the work is done it’s up to others to respect the surface

After completion and inspection of the concrete stained floor, it is the responsibility of the homeowner, business owner, general contractor, and/or builder to protect the stained concrete or concrete overlay floor.

Beware leaving marks from furniture

Heavy furniture can scratch the surface especially if you might have nails where your pads might have previously been located on the bottom of the legs so be sure to check. I recommend felt pads, magic movers, or similar items that are durable and relatively inexpensive.

Maintenance

Your concrete stained floor needs to be vacuumed or dust mopped periodically and an occasional damp mop using a neutral cleaner which can be purchased at Home Depot. That is all that is required to maintain your floor. You will need to apply a floor finish 1-2 times a year which will take 15 minutes and 30 minutes to dry.

Conclusion

There are many marks on this list to be checked, but doing so will help you get the best stained floor possible. Professionals usually agree, but a little tact will help you to avoid occasional disagreement.

Nobody likes to prepare the field for another so it’s good to present these things in the proper way to avoid unnecessary trouble.

To read more about this subject, move on here to know what affects the cost of concrete staining.