Surface Preparation - QA Assessments (con’t)

• Extent/quality of feathering required• Test the integrity of the coating that remains after

cleaning

Moisture Content – QA Assessments

• Examine surface for unacceptable levels of moisture.

Moisture Content – QA Assessments

• Sources include pre-existing moisture, moisture from pressure washing, and external sources such as leaks and ground water

Moisture Content – QA Assessments (con’t)

• Moisture meters and plastic sheet tests (ASTM standards; SSPC standard under development)

Coating Material and Mixing – QA Assessments

• Schedule QA inspection to verify complete mixing– Hand/mechanical/boxing– Thinning (within VOC limits)– Partial kits– Pot life

• Confirm that the correct coatings and colors are applied – can be very complicated when many substrates involved

Coating Application – QA Assessments

• Pay attention to limited access areas and difficult configurations

• Stripe coats on steel

Coating Application – QA Assessments(con’t)

• Back rolling and back brushing

Coating Application – QA Assessments (con’t)

• Correct number of coats applied

• Drying time between coats• Cleanliness between costs

Coating Application – QA Assessments (con’t)

• Wet film thickness during application (ASTM standard)

Coating Application – QA Assessments (con’t)

• Dry film thickness (non-destructive) – concrete and steel (ASTM and SSPC standards)

Coating Application – QA Assessments (con’t)

• Dry film thickness (destructive) – concrete and steel (ASTM standard)

Coating Application – QA Assessments (con’t)

• Pinholes and coverage • (SSPC pinhole guide

under development)• Weep Spouts

Coating Application – QA Assessments (con’t)

• Continuity/Air barrier (ASTM Standard)

Coating Application – QA Assessments (con’t)

• Continuity of Sealant• Rilem Tube

Surface Preparation Standards Cleanliness

• SSPC-SP1 through SP16 (solvent, hand/power tool, abrasive blast cleaning, waterjetting)

• SSPC-VIS1 through VIS 5 (hand/power tool, dry blast, wet blast, waterjetting)

• SSPC-SP13/NACE No. 6, Surface Preparation of Concrete

• ICRI Guideline No. 310.2 (formerly 03732), Selecting and Specifying Concrete Surface Preparation for Sealers, Coatings, and Polymer Overlays

Surface Preparation Standards Roughness

• ASTM D4417, Standard Test Methods for Field Measurement of Surface Profile of Blast Cleaned Steel

• SSPC-PA17, Procedure for Determining Conformance to Steel Profile/Surface Roughness/Peak Count Requirements

• ICRI 310.2-9, Concrete Surface Profile (CSP) Coupons

Surface Preparation Standards Moisture and Containment

• ASTM D4263, Standard Test Method for Indicating Moisture in Concrete by the Plastic Sheet Method

(Many ASTM standards are available for moisture testing of floors using instruments, calcium chloride, RH probes; SSPC is currently developing a guide for testing moisture in walls)

• SSPC-Guide 6, Guide for Containing Surface Preparation Debris Generated During Paint Removal Operations

Coating Thickness Standards

• ASTM D4414, Standard Practice for Measurement of Wet Film Thickness by Notch Gages

• SSPC-PA2, Procedure for Determining Conformance to Dry Coating Thickness Requirements

• ASTM D7091, Standard Practice for Nondestructive Measurement of Dry Film Thickness of Nonmagnetic Coatings Applied to Ferrous Metals and Nonmagnetic, Nonconductive Coatings Applied to Non-Ferrous Metals

Coating Thickness Standards (con’t)

• SSPC-PA9, Measurement of Dry Coating Thickness on Cementitious Substrates

• ASTM D6132, Standard Test Method for Nondestructive Measurement of Dry Film Thickness of Applied Organic Coatings Using an Ultrasonic Coating Thickness Gage

• ASTM D4138, Standard Practices for Measurement of Dry Film Thickness of Protective Coating Systems by Destructive, Cross-Sectioning Means

Coating Characteristics

• ASTM D4214 Standard Test Methods for Evaluation Degree of Chalking of Exterior Paint Films

• ASTM D3359, Standard Test Methods for Measuring Adhesion by Tape Test

• ASTM D4541, Standard Test Method for Pull-Off Strength of Coatings Using Portable Adhesion Testers

• ASTM E1186, Standard Practices for Air Leakage Site Detection in Building Envelopes and Air Barrier Systems

• (SSPC is currently developing pinhole standard and a guide for laboratory testing of thin film coatings on CMU to serve as air barriers)

QA Assessment Checklist

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Item Spot QA Inspection Results

1 Proper equipment on-site for access, surface preparation (pressure washing, blasting, etc.), and paint application (brush, roll, spray)

2 Required materials on-site – e.g., stripper, abrasive, mortar, patching material, backer rod, sealant, paint, etc.

3 Environmental controls on-site – containment materials, masking materials, water filtration, etc.

4 Test patches performed to examine wall repairs, sealants, surface cleanliness and roughness, paint coverage, and final appearance

5 Tuckpointing – compatible mortar used that matches strength, type, and color of existing, and sealant not used in lieu of mortar

6 Block repair acceptable – cracks, block faces, block replacement per specification; flush; mortar sound; excessive cracking referred to structural engineer

7 Joint replacement acceptable – joint cleaning, existing coating removed, closed cell backer rod, primer (if required) and sealant type as specified

QA Assessment Checklist (con’t)

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Item Spot QA Inspection Results

8 Ambient conditions acceptable – air temperature, surface temperature, relative humidity, dew point, no rain, dew, or snow

9 Adhesion of the existing coating suitable for overcoating 

10 Surface preparation for overcoating – chalk, grease, dust, efflorescence, loose coating, bridged coating, de-glossing, etc.

11 Surface preparation for total coating removal – extent of paint removal, texture/damage of substrate, etc.

12 Substrate moisture content acceptable –visually, instrumentation

13 Paint application – correct products, color, mixing, shelf life, pot life, number of coats, proper thickness

14 Paint application methods acceptable – spraying, rolling, back-rolling, brushing, back-brushing

QA Assessment Checklist (con’t)

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Item Spot QA Inspection Results

15 Paint coverage acceptable – pinholes, skips, misses, runs, curtains sags, overspray, overlap, splotchy appearance, shadow through, air leakage, etc.

16 Daily housekeeping acceptable 

17 Final coverage and appearance acceptable, all specified items completed, removed items are replaced, final clean up acceptable, etc.

More Information• More information on the topics in this webinar can

be found in an article written by Ken Trimber and Kevin Brown – KTA, published in Durability+Design magazine:

– Jan/Feb 2014 – Spot Assessments of Ongoing Cleaning and Painting Projects

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Questions?

Ken Trimber – 412-788-1300, x204 (ktrimber@kta.com)