Painting guide
Nashville Interior Repaints: Which Nail Pops, Cracks, and Patches Need Repair?
On this page
Paint does not hide wall defects. It lights them.
A fresh coat is uniform in color and sheen, which means every interruption in the surface underneath becomes more visible rather than less. The small circular bump you have been ignoring for two years is considerably more noticeable on a newly painted wall than it was on the old one.
So the walk-through happens before anything is bought, and it sorts what you find into three piles: repair, leave, and investigate.
What the wall is made of is a different question from what is wrong with it. Plaster and drywall crack differently and take a repair differently, so which one you are standing in front of is worth settling before you start, and that is Older Nashville Homes: What Changes When Repainting Plaster vs. Drywall?; this page is about which of the findings in front of you actually need work before paint.
Nail pops
You are looking for a small circular bump, sometimes with a hairline crack around it and sometimes with the fastener head visible through a broken surface. They turn up in rows or scattered, and they follow the line of a stud.
What is happening. The bump is wall material being displaced from behind, not the nail growing. More than one thing can push it out. Movement in the framing is the explanation usually given. There is at least one other that has been documented: a manufacturer investigation into raised circular bumps directly above fasteners, which contractors described as being like a nail pop, traced them to the adhesive behind the panel shrinking as it dried rather than to the fastener moving. What the two have in common is the part that matters to you, which is that something behind the surface is pushing it out, and it is not the filler you are about to put on top.
Why filling alone fails. Filling over the bump adds material to the surface without addressing the fastener that pushed it out. The framing moves again next season and the same defect reappears, now with a patch on top of it. Any repair that gets done twice is worth suspecting for this reason, and a nail pop filled without touching the fastener is the clearest example of it.
What to do about it. The fastener has to be dealt with rather than covered: driven properly, removed, or supplemented by a second fastener nearby that holds the panel while the original is set below the surface. Filling and sealing follow. Where closing the repair also means sanding, that step waits on the condition set out further down this page.
Which ones need it. All of them that are visible in normal light, because they will all be more visible after painting. A pop you can feel but not see may be left, and it may show up later.
Cracks are the other defect that appears in every house, and unlike pops they are not all the same finding.
Hairline cracks
These run fine and usually straight, and they show up at the corners of door and window openings, along ceiling lines, and at the joints between wall panels.
Cosmetic movement. A house moves seasonally. Materials expand and contract at different rates, and joints between materials open slightly. A fine crack at the corner of a door frame that has been the same width for years, does not step, and is not accompanied by any other symptom, is the building doing what buildings do.
Something worth a second look. A crack has earned closer attention if it has widened noticeably, or if one side of it now sits proud of the other, which makes it a step rather than a gap. The same is true of a crack running diagonally from the corner of an opening and continuing out across the wall, and of any crack that arrives alongside doors or windows that have become difficult to close or floors that have changed. And a crack that reappears in the same place within months of a competent repair belongs in this group whatever it looks like.
How to tell them apart in practice. That last one is the check a homeowner can run without any expertise, because it requires nothing but time. A crack filled properly and reopening along the same line is telling you that something behind it is still moving. A crack filled once and staying closed was simply a crack.
Old patches that still show
These are previous repairs that sit flat to the wall and still read, under certain light, as a patch of different sheen or texture.
Absorbency. Patching compound absorbs more of a coating than the painted wall around it. If it was not sealed before painting, the finish sank in and the patch reads as dull against the surrounding sheen. Another coat of finish over it usually does not fix this, because the absorbency difference is still there.
Texture. A smooth patch on a wall with any texture shows regardless of how well the color and sheen match, because the eye reads texture through shadow rather than through color.
What to do. Seal the patch before the finish coat. If texture is the problem, the patch has to be textured to match, which is the part that requires skill and the part most often skipped.
There is one thing that looks like this and is not. If what shows through is a discoloration rather than a difference in sheen or texture, the wall is not flashing a repair at you but carrying something that is coming up through the film from underneath, and sealing the patch will not reach it.
When it stops being a painting question
Some findings take the wall out of the painting conversation altogether, and it is worth recognizing them early.
Cracks that are widening, stepping, running diagonally out of an opening, arriving alongside doors and windows that no longer operate as they did, or reopening after a competent repair are combinations that stop the paint conversation.
That combination is not this page’s invention. HUD’s national inspection standard for foundations tells an inspector to look for indicators of foundation cracking, and gives the examples as “cracks in walls, no functioning doors, unlevel floors or windows”. Note what it does with them: they are indicators that send the inspector to look at the foundation, not a finding in themselves.
This page uses them the same way. It does not tell you those cracks are structural, because no diagnosis is available from looking at one and none is offered here. What it says is what to do with them: stop treating the crack as a paint-prep defect, and have the movement looked at by someone whose work is structure before anything covers it. Filling and painting conceals a signal that somebody should be reading, and that is the whole of the risk.
The same applies to anything soft, damp, stained or crumbling, which is a moisture question rather than a defect question. A stain that keeps coming back through fresh paint is not a coverage failure, it is something still arriving at that spot or something still in the material, and painting it again produces the same stain on a newer wall. Whatever is producing it gets resolved first, and the repaint waits on it.
Before you sand a patch
If the house predates 1978, settle the lead-safe question before sanding starts. Sanding filler and feathering repairs into the paint around them takes some of that paint off, which on a house of that age brings a federal rule into the room, so settle it with Painting a Pre-1978 Nashville Home: When EPA Lead-Safe Rules May Apply first. A wall with several repairs in it is exactly the case worth checking, and the time to check is before the sanding block comes out.
Walking the room
Do it with a light held close to the wall and angled across it rather than pointed at it. Raking light shows surface irregularity that flat light hides completely. Work one wall at a time, top to bottom, and mark what you find with low-tack tape rather than trusting memory.
Defects do not distribute evenly, so walk the places they collect before walking the open field of the wall: outside corners, where the bead under the surface takes contact from furniture and shoulders; the taped joints between panels, where a crack runs straight for the width of a panel; the wall-to-ceiling line, where two planes move independently; and the corners of door and window openings, which concentrate stress and are where the second-look criteria matter most.
Then sort what you found into three piles. Fix anything that will be more visible after painting than before: pops, stable cracks, previous patches that show, dents and gouges deep enough to catch light. Accept, usually, gentle undulation across a plaster wall and minor variation in a taped joint that shows only in raking light from one angle, because chasing those means skim coating and a different project. Investigate anything meeting the second-look criteria, anything soft or damp, and anything repaired before that came back.
The line between the first two is worth setting consciously rather than discovering with a sanding block in hand. Switch the light off and walk the room again from where you normally stand. What is still visible gets dealt with; what disappeared was a viewing condition rather than a defect, and the tape comes off. Raking light is how you find things and ordinary light is how you decide about them.
Sources. Both opened 10 September 2026.
- Sherwin-Williams, obvious repair or touch-up:
https://www.sherwin-williams.com/painting-contractors/products/resources/SW-ARTICLE-PRO-OBVIOUSREPAIR. It defines the problem as a repaired or repainted area that is noticeably different from the surrounding space, and names among the causes applying the touch-up with a different tool from the one used originally, using a different batch of paint, a repair whose texture differs from the surrounding surface, and applying at a temperature very different from the original application. - USG, Fastener-Related Drywall Installation Issues and Recommendations, white paper WB2757:
https://www.usg.com/content/dam/USG/pdpmovedocuments/usg-fastener-related-drywall-installation-issues-eccomendations-white-paper-WB2757.pdf. Source for the alternative cause named above. Contractors reported a raised circular protrusion directly above the fastener, described as similar to a nail pop, appearing from a few days to several months after the drywall was hung and finished, and the investigation attributed it to shrinkage in the adhesive behind the panel as it dried.
- HUD, National Standards for the Physical Inspection of Real Estate: Foundation, version 3.0, published 20 June 2023:
https://www.hud.gov/sites/dfiles/PIH/documents/NSPIRE-Standard-Foundation_20230620.pdf.hud.govreturned HTTP 403 to automated requests from this machine, and a deliberately invalid path on the same host returned 403 as well, so the status code carries no information; the document was read through the Internet Archive’s stored copy on 10 September 2026. Source for the indicator list quoted above.
Nothing on this page publishes a crack width, and nothing on it diagnoses a structure. HUD’s own standard measures a crack and refers the question onward; this page does not measure and does not refer it anywhere but to someone who can.