Hamilton Drywall Products

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Delamination of texture on drywall surfaces is an expensive and apparently increasing problem. Job site investigation of this problem reveals not one cause, but several. Read more >>>

Dark and Light Bands

Probably the most perplexing problems encountered on textured ceilings are those of dark or light bands over the joints of the wallboard surface. This condition, in the language of the trade is commonly referred to as "Photographing". The terms "Burning", "Flashing", "Banding", "Bleeding", and "Shadowing" are also used to describe the color variation.

Although "Photographing" is used as the major descriptive term, there are actually three conditions which occur and are frequently confused

Actual color differential between joints and the field of the wallboard.

Texture pattern differential between the joints and the field of the board, resulting in a variance of the degree of light reflection.

Joints which are not finished to the plane of the wallboard surface known as "humped" or "starved" joints, which result in shadowing.

There are several variables of these three basic conditions with different causes, solutions, and methods of repair. The following are the more common problems along with our recommendations to avoid them , or to repair them should they occur.

White Bands Over Ceiling Joints

Cause:

Discoloring agents leaching out of the wallboard face paper and migrating to the surface of the texture. This phenomenon is influenced by the age of the paper, heat, and humidity.

Texture pattern differential over joints.

Prevention:

Completely seal entire ceiling surface prior to application of texture.

Repair:

Seal surface and "fog" with wall texture or alkyd flat paint. In some cases where the discoloration is slight, the application of household bleach will be sufficient to produce satisfactory result. Re-spraying with ceiling texture may be necessary when correcting a pattern differential.

Dark Bands Over Ceiling Joints

Cause:

There are several potentials of this condition.

	1.	"Starved" or "humped" joints, resulting in shadowing.
	2.	Variance in texture pattern due to suction differential between board and joint. This results in a lower light reflectancy over the joint and appears darker.
	3.	Joints not completely dry.
	4.	Application of texture over joint compound before it has completely dried.
	5.	Application of texture over "chemically hardening" or "setting" type joint compounds.
	6.	Overthinning texture mix.
	7.	Allowing bacterial buildup in spray equipment.

Prevention (for causes listed above):

Finish joint as close to plane of the board as possible.

	2. & 5.	Seal surface prior to application of texture.
	3. & 4.	Adjust job schedule to weather conditions. Allow adequate drying time. Provide temporary heating, if necessary.

	6.	Mix texture to heavy consistency.
	7.	Keep equipment clean and disinfect periodically or at first indication of odor, discoloration or foaming.

Repair (for causes listed above):

	1.	Scrape off texture, "fill" or "feather" joint as required, seal, and re-texture.
	2.	Sweep edges of joints with ordinary kitchen broom. If texture pattern is not suitable, seal and "fog" with second coat of ceiling texture.

3. & 4.

Allow joints to dry completely. Maintain 55° F minimum job temperature and allow adequate ventilation.

	5.	Seal entire area and "fog" with wall texture.
	6.	Seal and "fog" with second coat of ceiling texture.
	7.	Spray with household bleach, exercising extreme caution for your person and surrounding finish materials. If necessary, seal and apply second coat of ceiling texture. (In extreme cases, additional treatment may be required. Contact our representative if this condition persists.)

Note: It is a common "job practice" to treat this problem with a spray application of a 50% bleach/water solution. Although this practice is normally successful, we cannot recommend the procedure due to the health hazards of spraying the solution, and the possible damage to the ceiling texture and other materials.

In addition to the conditions and problems outlined in the preceding, there are several other coloration problems which may be encountered. For additional information, see the following technical bulletins:

Surface Porosity: A New Problem
Bacteria: The Spray Mans Nemesis
Respraying: Common Questions, Simple Answers
Seasonal Adjustments: Problem Saver