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Paint Flashing and Roller Marks: The Dull Patches Over the Joints and the Stripes Down the Wall, What Causes Each, Whose Fault It Is, and the Fix
Drywall, Taping & Painting
Flashing, Roller Marks and Lap Marks: The Four Ways a Painted Wall Looks Wrong From the Side, and the One Fix That Works for All of Them
Stand in the doorway with the window behind you and the wall is fine. Stand at the window and look along the wall and it is a mess: dull rectangles, shiny stripes, a band along the ceiling, a patch where somebody touched up. None of it is visible head on, all of it is visible every afternoon, and the painter says it looks fine to him from where he is standing. Here are the four things that are going on, which ones the painter owns, which the drywaller owns, and why the fix is almost always “prime and paint the whole wall” rather than anything clever.
The four problems
| What you see | Name | Cause | Whose | Fix |
|---|---|---|---|---|
| Dull or shiny patches, usually rectangles or 12-in. stripes over the drywall joints, or a patch where a repair was. | Flashing | Different absorption under the paint: unprimed compound, a patch painted without primer, a touch-up on a sheen paint, or primer thinned to a wash. | Painter. (Drywaller if the compound was oversanded to fuzz, rarely.) | Prime the whole wall with a proper primer, two finish coats corner to corner. Primer. |
| Stripes down the wall the width of a roller, alternating slightly lighter and darker or textured and smooth. | Roller marks | Too little paint on the roller, the wrong nap (a short nap on textured board or a long nap on smooth), too much pressure, or rolling after the paint started to set. | Painter. | Light sand if there is a ridge, then a full wet coat with the right nap, rolled in a W and finished in one direction, corner to corner. |
| A band or line where one section of wall meets another, like a seam in the paint. | Lap marks | Painting a wall in sections and letting one edge dry before the next section overlaps it. Worse with premium paints that dry fast and in hot rooms. | Painter. | Repaint the wall keeping a wet edge, top to bottom, no stopping mid-wall. |
| A shinier or duller band along the ceiling line and around the trim, 2 to 3 in. wide. | Cut-in band (picture framing) | The brushed cut-in dries to a different texture and sheen from the rolled field, especially with sheen paints and when the cut-in is done for the whole room before rolling. | Painter. | Cut in and roll one wall at a time so the roller overlaps the wet brushwork; or a flat/matte paint that hides it. |
Why touch-ups make it worse
A touch-up is a small patch of fresh paint on an older film. Even from the same can, it has a different thickness, a different texture from the roller or brush, and a different sheen because it dried under different conditions. On flat paint and in the first month, it can vanish. On eggshell, satin or anything older, it flashes, and now you have a flashing patch in the middle of a wall that was otherwise fine. The honest rule for anything above matte: repaint corner to corner, or leave it. The repair calculator prices the repaint for exactly this reason.
How a good painter avoids all four
- Primer on anything new, patched or stained, full strength, before colour.
- The right roller: 10-mm nap on smooth Level 4 or 5 drywall, 13 to 15 mm on texture. Loaded, not dripping. New sleeve for the finish coat.
- One wall at a time, wet edge, top to bottom. Cut in a section, roll it while the cut-in is wet, move along. Never leave a wall half done for lunch.
- Two full coats, not one and a half. The second coat is what evens the sheen.
- Check from the window, not the door, before calling it done. The checklist.
Questions people ask
What causes paint flashing on new drywall?
No primer, or the wrong primer. Compound and paper absorb the finish paint differently and the joints dry to a different sheen. The fix is a coat of drywall primer and two coats of paint over the whole wall; another coat of the same paint does not fix it.
Why can I see roller marks after painting?
Too little paint on the roller, the wrong nap, or rolling over paint that had started to set. The fix is a full wet coat with the correct roller, finished in one direction, over the whole wall.
Will another coat fix roller marks?
A proper full coat, yes, usually. A thin third coat rolled the same way, no. If there are ridges you can feel, a light sand first.
Can you touch up paint without it showing?
On flat or a premium matte within a few weeks, often. On eggshell and up, or on paint more than a season old, rarely. Repaint corner to corner.
Not sure which one you have?
The seams-after-painting page separates the paint problems from the taping problems with a flashlight test. If you have photos and two trades pointing at each other, the $99 review will tell you which one it is.
Sources and further reading
- Gypsum Association GA-214, Levels of Finish: the standard every “Level 4” and “Level 5” on a quote is supposed to mean. Free summary on the Gypsum Association site.
- Benjamin Moore Canada: product data sheets for the primers and paints named on these pages: coverage per gallon, recoat times and the right primer for new drywall.
- Sherwin-Williams Canada: the other paint line most Ontario painters use; the data sheets say the same things in different words.
