Almost nobody chooses a painter based on how they sand. But sanding, patching and cleaning are what actually determine whether your walls still look good in five years — the paint itself is the easy part. Here is what proper interior prep looks like, so you know what to ask for and what to watch for.
1. The walls have to be clean, not just dusted
Paint bonds to a surface. It cannot bond to grease, dust, smoke residue or the film left behind by cooking and candles. In kitchens, hallways and anywhere near a stove, that film is heavier than it looks, and it is the single most common reason paint peels away in sheets a year later.
Walls should be washed with a degreasing cleaner and allowed to dry completely before anything else happens. It is unglamorous, it takes real time, and it is not optional.
2. Every hole gets filled — and then sanded flat
Filling a nail hole takes seconds. Sanding it flush so it disappears under a raking light takes longer, and it is the step that gets skipped. A patch that sits even slightly proud of the wall will catch light forever, and no amount of paint hides it.
The same applies to old anchor holes, dents behind door handles and hairline settling cracks. Cracks in particular need to be opened up slightly and taped, not just filled — otherwise they reappear through the new paint within a season.
3. Caulk closes the gaps paint cannot bridge
The line where trim meets wall, where crown meets ceiling, and where baseboard meets drywall will all show a shadow gap if they are not caulked. Painting over an uncaulked joint produces a dark line that reads as sloppy even when the paint itself is perfect.
A thin, tooled bead of paintable caulk on those joints is what makes a repaint look like finish work rather than a coat of colour.
4. Primer is not always necessary — but when it is, it really is
You do not need to prime every wall. You do need to prime bare patched compound, any stain that could bleed through, raw wood, glossy existing finishes and dramatic colour changes. Skipping primer in those situations means either a visible flash spot or three coats instead of two.
- Fresh drywall compound — always prime, it drinks paint unevenly
- Water stains, smoke or marker — spot-prime with a stain-blocker
- Glossy or oil-based existing paint — scuff-sand and use a bonding primer
- Dark to light colour changes — a tinted primer saves a full topcoat
5. Masking protects more than the floor
Drop cloths on the floor are the minimum. Proper protection also means covering furniture, masking window frames, removing switch and outlet plates rather than cutting around them, and taping off flooring edges at the baseboard.
Removing hardware instead of painting around it is a small detail that shows in the final result more than almost anything else.
The bottom line
If a painting quote seems unusually low, prep is almost always where the savings came from — and prep is the part you cannot add back later. Ask any painter to walk you through their prep sequence before you compare prices.
Want this done properly?
We handle painting work across Garland and the DFW metroplex. Free estimates, honest pricing, prep-first workmanship.