Crackle Surface Preparation and Protection

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Please read this section carefully. As we learn more about the use of the Crackle products in conjunction with other brands we will add our test results here.

Decorative painting is full of variables. How one wall accepts glaze may be different than another in the same room. Controlling your situation is critical for consistent decorative painting results.

Proceed Crackle products are designed to produce a consistent and controllable cracking pattern that will dry to a durable surface. These cracking products adhere tightly to the substrate as they fracture. At the same time, they stress the layers of paint and other products underneath. If there is a layer with weak adhesion anywhere beneath the cracking product, as the cracking texture moves, cracks and dries, it may cause that layer to separate from the layer below and there will be a loss of adhesion.

Therefore, to increase your success rate, please review all of the information shared in the Crackle section of the Proceed-e-pedia.

Contents

Extensive Crackle Testing and Base Layer Considerations

Extensive Crackle testing conducted at GOLDEN

Interior architectural coatings are formulated to optimize a set of attributes not related to decorative painting. For example, consumer ratings typically grade interior paints on: spatter, hiding, stain resistance, scrub resistance, mildew resistance, VOC content, and cost. We've tested many of the leading brands and sheens of interior acrylic wall paints, and have found that they all produce slightly different results with the Proceed Crackle products.

The manufacturers of interior architectural coatings regularly change their formulations to incorporate new resins and additives. In most cases, these changes have a minimal effect on the performance of decorative products (glazes, metallic paints, textural coatings) that are used over the top of them because they form a continuous film. However, because cracking products are designed to shrink and move as they cure, small differences in the absorbency and surface characteristics of the base coatings will have an effect on the performance of cracking products. It is impossible to test every possible product combination.

Our cracking products were developed for optimal performance over two coats of Proceed Low Absorbency Base Paint. As a result, we have observed the best and most consistent adhesion and cracking patterns when Proceed Low Absorbency Base Paint is used both as a primer and base color as part of our Crackle System.

Does this mean that Proceed Cracking Textures cannot be used with other brands of interior paints? Not at all. But because paint manufacturers do change their formulas over time, the only way to insure the performance of your finish combination is to produce a new control sample for each application.

The “history” of the wall is often unknown. Weak spots are usually undetectable to the eye. To minimize the chances of unexpected adhesion loss, follow these recommendations:

  • If you intend to use the cracking textures in thick applications – do not use Crackle Size. The fundamental rule to follow when applying Rough Cracking and Smooth Cracking Textures is to avoid excessively thick applications over Cracking Size. At coverage rates of 75 mils (19 sq.ft./gallon) or more, the Cracking Size has little effect on the size of the cracking patterns and will aggravate adhesion problems or cause slumping of the Cracking Texture.
  • If your finish design relies on random thick spots to produce the visual accent of a larger cracking pattern, we do not recommend using Crackle Size beneath the texture.
  • If your finish calls for a larger cracking pattern over a large surface area, it is more cost effective to use Cracking Size (1 or more coats) and apply the cracking texture thinner, at a thickness of less than 25 mils (coverage rate of 58 sq. ft./gallon).

See: Crackle: Minimum and Maximum Thicknesses.

The combination of primer and base paint and sheen of the base paint will influence the ultimate crackle effect achieved. This in large part is due to the absorbency of the primer influencing the "sealed" quality of subsequent layers of paint.


Rough Cracking Texture at 50 mils or 21.5 sq. ft/gallon over 1 coat of Crackle Size over Flat, Satin and Semi-Gloss Sheens (pics left to right) of a major architectural paint brand. Notice how the increase of sheen influences the size of the crackle pattern to the point of losing adhesion of random platelets


For more in-depth information and images from our Extensive Crackle Testing, view the pages: Rough Cracking Texture, Surface and Underlayer Considerations Smooth Cracking Texture, Surface and Underlayer Considerations

Our Best Recommendation For New Construction:

To specify preparation of the walls: Do not skimcoat the walls with any plaster. Make sure all sanding dust is removed. Use Proceed Low Absorbency Base Paint as the primer and paint (2-4 coats). Follow all other recommendations as described on other pages.

Typical weak spots occur over taped drywall seams and spot repairs where drywall compound has been sanded and primer applied over the dusty surface. Extra attention and applications of paint to ensure a clean, dust free and sealed surface is essential.

Patching plaster and skim coating materials, in particular, present a very unstable surface for cracking textures and use of Crackle Textures should be avoided over these surfaces.

If "contractor white" primer has already been applied:

  • Test methods to use to determine if there is a layer of plaster beneath layers of primer/base paint:

Create a "reveal": Borrowing from the paint conservation world, simply use a sharp x-acto knife or blade to scrape back thru the existing paint layers. If at any point you find a layer of chalky surface, this means the wall has been "skimmed" with joint compound or patching plaster and using the Crackle materials should be reconsidered.

Scratch adhesion test in the corner of a room: Corners are often not given as much care and attention as the rest of the wall and will reveal any "weaknesses" in wall preparation. Using a pin or sharp tool, scratch a tic-tac-toe pattern into the wall paint. Apply a piece of masking tape (not low tack painters tapes) and burnish it with your thumb. Pull the tape from the wall. If all of the paint squares are still on the wall, there is good adhesion of previous layers of paint. If some of the squares are on the tape, the wall preparation is questionable and a crackle finish should be reconsidered.

An alkyd primer should be applied if a chalky layer has been discovered before applying Proceed Low Absorbency Base Paint.

Our Best Recommendation for Existing Construction with previous painted layers:

- If you suspect the surfaces were skim coated with plaster, patching plaster or joint compound:

  • Consider not applying a Crackle finish.
  • Keep the Smooth and Rough Cracking Texture applications thin.
  • For a more pronounced crack, use one or more coats of Crackle Size over Proceed Low Absorbency Base Paint and apply the crackles thin. An application of Crackle Size will seal the surface and allow the Crackle Textures to adhere over skim coats of plaster.
  • Test methods to use to determine if there is a layer of plaster beneath layers of base paint:

Create a "reveal": Borrowing from the paint conservation world, simply use a sharp x-acto knife or blade to scrape back thru the existing paint layers. If at any point you find a layer of chalky surface, this means the wall has been "skimmed" with joint compound or patching plaster and using the Crackle materials should be reconsidered.

Scratch adhesion test in the corner of a room: Corners are often not given as much care and attention as the rest of the wall and will reveal any "weaknesses" in wall preparation. Using a pin or sharp tool, scratch a tic-tac-toe pattern into the wall paint. Apply a piece of masking tape (not low tack painters tapes) and burnish it with your thumb. Pull the tape from the wall. If all of the paint squares are still on the wall, there is good adhesion of previous layers of paint. If some of the squares are on the tape, the wall preparation is questionable and a crackle finish should be reconsidered.

An alkyd primer should be applied if a chalky layer has been discovered before applying Proceed Low Absorbency Base Paint.

- If you know there has not been any skim coating with plaster, patching plaster or joint compound:

  • Keep the Smooth and Rough Cracking Texture applications thin. Apply Crackle Size beneath to create larger crackled finishes.

- If applying "random" thick (1/4") applications, do not use Crackle Size beneath them.

Surface Preparation and Repair Advice

Follow normal surface preparation procedures (may include sanding, wiping, washing, allowing the surface to dry, etc.) as you would for any painting project, cleaning and dusting the walls down between each step is very important. Dust leftover from sanding sheetrock joint compound beneath the primer may result in delamination of the primer film. Take care to ensure that sanded drywall seams and patches are free of sanding dust before applying Proceed Low Absorbency Base Coat.

SPECIAL NOTE: Poor adhesion of underlayers could cause the crackle, along with previous layers of paint, to lift all the way down to the weakest point. For example, dust left from sanding the sheetrock mud beneath the primer may cause the crackle to pop or lift off of the wall revealing the sheetrock itself in random areas. This does not mean the entire surface will lose adhesion.

GOLDEN can not predict when and where lifting may occur. However, here is our best recommendation on how to handle the occurence of lifting:

Before the job begins, explain the performance combination of primer and base paints as noted in the Extensive Testing section above. If working on a previously painted surface, the history of the walls will probably be unknown. No one can predict completely what will happen whenever a decorative finish is applied, crackled or not. There may be weak points in the underlayers of paint and it should be expected that there will be points of lifting on occasion - an applicator should plan on making some minor repairs.

To fix areas which reveal the chalky surface of joint compound or plaster: Sand, thoroughly clean the sanding dust off of the surface, reprime with an alkyd primer like: Benjamin Moore Fresh Start or Kilz Alkyd primers. Alkyd primers will do the best job at locking in the plaster when applied directly to the plaster. Repaint as necessary (preferably with Low Absorbency Base Paint) the areas affected and reapply the crackle materials. A waterbased alternative is a PVA Primer (Pratt & Lambert, Glidden, & Behr) but the best recommendation would be an alkyd.

It is possible that over previously painted layers, random "platelets" or "islands" may lose adhesion. It does NOT mean that all of the finish will lose adhesion. If buckling or complete loss of adhesion occurs with random platelets:

  • simply push the platelet into the surface, making contact with the tacky Crackle Size (if used);
  • apply Crackle Size, paint or an acrylic medium to "glue" the platelet back into place;
  • and/or, work the opening or space into the overall design of the finish.

Summary

  • Gather as much information as possible about the surface you are working on in order to anticipate potential problems.
  • Always prepare a control sample using the same products that will be used on the jobsite. We recommend using ¼” sheetrock supported on a vertical surface, as this will alert you to any issues such as “slumping” that might occur with heavier applications.
  • Examine dried test panels closely for any loss of adhesion between layers.
  • For greatest reliability and to create the best adhesion and the most interesting crackle pattern use Proceed Low Absorbency Base Coat as primer and paint beneath our Crackle System.
  • Other brands of base paints may be used, but performance will vary. You should always test your finishing system before applying the job.
  • Proceed Cracking Textures generally adhere well to other brands of primers and base paints in various sheens, except Semi-Gloss or Gloss.
  • Proceed Cracking Size may be affected by the surface characteristics of other brands of primers and paints. Avoid working over semi-gloss sheen, pay attention to the sheen recommendation/crackle product and test for good adhesion. Use thin applications of cracking textures in conjunction with the Cracking Size if working over other brands of paints.
  • To create the best adhesion and the most interesting crackle pattern: use Proceed Low Absorbency base paint as primer and paint beneath our Crackle System.
  • Prepare yourself, there may be points of lost adhesion, this is no fault of the crackle products or often, the applicators.

Protecting the Crackled Surface

The degree of protection required is determined by the location and use of the surface. Wider cracks may need more protection simply due to the vulnerability of a crackled surface. The Proceed Crackle products create durable surfaces that clean easily but will not chip easily.

Crackle Textures can be glazed and with a proper amount of time for drying, may be topcoated with almost any proven topcoat for the situation. If overglazed, the glaze itself will be more sensitive and is in need of adequate curing time before applying the protective top coat. Apply Smooth Transparent Glazing Gel: the "extra body" will work to fill in gaps and literally provide extra "glue".

Regarding protective topcoats, we do not have specific brand recommendations and we highly recommend testing for each application.

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