How to Get a Surface Preparation Job off to a Good Start

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Job Planning For Architects, Engineers, Property Owners, and Other Important People

You can never be too prepared. The information below will help you get organized before starting surface preparation work. Without taking these things into consideration, you could end up doing more harm than good.

Job planning requires the important people in a project know any special requirements they have prior to the project being put out to bid.

      • Time schedules
      • How work will be done around existing operations
      • Allowing drying time if water is used in the surface preparation process
      • Acceptable levels of dust
      • Possible fumes
      • Noise levels
These are all problems that can be avoided if known about and planned for ahead.

Examine the Surface

surface preparation

Laitance is a weak layer of cement and aggregate fines on a concrete surface that is usually caused by an over wet mixture, overworking the mixture, improper or excessive finishing or combination thereof. Also, could be caused when a slurry mix is used on a deep foundation, where the slurry mix is not completely removed before placing concrete on top.

Prior to contracting for a job or awarding a project – the contractor must conduct a survey of the concrete surface in its current shape.

If excessive laitance is present, this material must be removed down to solid concrete. The coating or overlay will not bond properly to the weak layer of concrete.

The surface should be checked for existing sealers, curing materials, grease, oil, efflorescence, and dirt that need to be removed. In short, you want no surprises.

 

Know the Job Specifications

Specifications should also say how uniform, clean, rough, and what strength the concrete substrate should be prior to a coating or overlay installation.

Proposals for surface preparation specifications should clearly spell out cleaning methods, profiling method, and surface defect repair procedures.

Other specifications may include time schedules and acceptable levels of noise and dust. Also, is there time in the schedule for concrete to dry to the required moisture level if water is being used in the cleaning process? If the specifications don’t cover these issues- make sure they get covered.

SURFACE PREPARATION SPECIFICATIONS AND STANDARDS

What Surface Condition Specifications Should Cover

Specifications should also say how uniform, clean, rough, and what strength the concrete substrate should be prior to a coating or overlay installation.

Other specifications may include time schedules and acceptable levels of noise and dust. Also, is there time in the schedule for concrete to dry to the required moisture level if water is being used in the cleaning process? If the specifications don’t cover these issues – make sure they get covered.

If testing is required, the types of tests should be incorporated into the specifications.

Proposals for surface preparation specifications should clearly spell out cleaning methods, profiling method and surface defect repair procedures.

Most job specifications for surface preparation state the surface should be “sound, free from surface defects dry, and clean.” Each of these terms is subjective, so it is important that the job specifications, the coatings or overlay specifications, and the expectations of the architect and/ or project engineer are in alignment.

Standards You Should Know About (ACI 503R, ASTM 4263, ASTM 4260)

      • ACI 503R Use of Epoxy Compounds with Concrete
      • ASTM D 4260-88- Standard Practice for Acid Etching
      • ASTM D 4262-83- Test Method for pH for chemically cleaned or etched Concrete Surfaces
      • ASTM D 4263-83- Test Method for Indicating Moisture in Concrete by the Plastic Sheet Method.

When Job Specifications and Manufacturers Specifications Differ

All of us in construction are familiar with the “I did it per the specs” excuse. It is when the job has gone south and a reason must be found as to why – so finger pointing begins. The problem is often the job specifications and the product specifications do not coincide.

Architects specifications are often boilerplate and transfer from one job to another, even when job conditions are different.

Contractors are busy and bid on many jobs – often with no time, or due to distance they are unable to examine the project specs versus the product specs and job conditions.

Owners often just don’t think it can be that complicated.

Smart owners, property managers, and designers will start at the end, considering the desired result and ask”, what is the end result of the new floor we are looking for”? Review reputable products that will produce that result.

Then write the specifications following the product manufacturers instructions for installation and considering the job conditions.

The above is not an easy task – but it beats the blame game that occurs when it is not done.

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