Most paint failures are prep failures. The paint was fine. What was under it was dusty, glossy, damp or loose. This page covers what has to happen before the finish coat on San Bernardino walls and trim.
Do I need to prime before painting?
You need primer on anything bare, stained, glossy or patched. That means new drywall, bare wood, bare stucco patches, water stains, smoke damage and slick old enamel. You also need it for a big color change. You do not need to prime a whole wall of sound, clean, flat paint that is getting a similar color.
Do I need primer if the old paint is in good shape, and can you paint over old paint?
Yes, you can paint over old paint, and no, you do not need primer when it is clean, dull and sound. Wash off grease and dust, fix the dents, spot prime the patches and paint. If the old paint is glossy, scuff it with sandpaper or use a bonding primer so the new coat can grip.
Do I need to sand the walls before painting?
Not every wall. Sand where it helps: over patches, on glossy paint, on drips and roller lint from the last job, and on all trim and doors. A flat wall in good shape only needs cleaning. Most local walls have orange peel or knockdown texture, and those are not sanded flat, only cleaned and spot repaired.
Do painters fix nail holes, cracks and dents first?
Yes. Filling nail holes, small cracks and dents is part of normal prep and part of our quote. So is caulking gaps between trim and wall. Nail pops, where a drywall screw or nail pushes out a bump, are reset and filled. Larger damage, such as a hole from a door handle, is a drywall repair and is listed on its own.
Hairline cracks at the corners of doors and windows are common in this area. Houses here move a little with dry soil and small earthquakes. We fill them, but some come back over time.
How do I paint over a water stain so it does not bleed through?
Fix the leak, let the area dry, then seal the water stain with a stain-blocking primer before painting. Regular wall paint will not hide it. The brown mark comes back through coat after coat. Stain-blocking primers are made to lock it in. If the drywall is soft or sagging, it needs to be cut out and replaced first.
Can you paint over smoke stains or pet smells?
Yes, with the right primer. Smoke from cigarettes, cooking or a fire leaves a film that bleeds through paint and holds odor. The walls are washed first, then sealed with a stain and odor blocking primer, then painted. Wildfire smoke is a fact of life near the San Bernardino foothills, and the same steps apply. Pet smells in walls are sealed the same way, but odor in carpet pad or subfloor has to be dealt with at the floor.
Mold on the bathroom ceiling: can it just be painted over?
No. Mold has to be killed and cleaned off first, and the moisture has to be dealt with, or it grows back through the new paint. For small spots of surface mildew, that means cleaning, drying, a stain-blocking primer and a bathroom paint. Then run the fan during and after showers.
A large area, mold that keeps returning or a musty smell behind the wall points to a leak or a ventilation problem. That is a job for a mold or plumbing professional. HomeGuide lists mold remediation for a small area at $500 to $1,500 as a national figure.
The paint is peeling to bare wood on my old house. What prep does it need?
Paint peeling to bare wood needs scraping to a firm edge, sanding to feather that edge, priming the bare wood and caulking open joints before any finish paint. Loose paint cannot be painted over. On sun-baked fascia and eaves, we also look for cracked and soft wood.
If the house was built before 1978, assume the old layers may contain lead until a test says otherwise. Scraping and sanding then have to follow lead-safe rules. See our lead paint page.
Why is my paint peeling?
Paint is peeling because it lost its grip on what is under it. The usual causes are moisture getting behind the film, paint applied over dust, chalk or gloss, and no primer on bare wood. Outside in San Bernardino, add sun. Years of heat make old paint brittle, and it cracks and lifts on wood that swells and shrinks.
Why is paint bubbling or peeling in my kitchen or bathroom?
Paint is bubbling or peeling in a kitchen or bathroom because of moisture and residue. Steam gets behind a weak paint film and lifts it into blisters. Soap film, hair spray and cooking grease stop new paint from bonding. The fix is to scrape and sand the loose areas, clean the surface well, prime and repaint with a paint made for damp rooms. A working exhaust fan keeps it from coming back.
How do I know if old paint is oil or latex, and can latex go over oil?
Rub the paint with a rag wet with rubbing alcohol. If color comes off on the rag, it is latex. If nothing comes off, it is oil-based. Latex can go over oil-based paint, but only after the surface is cleaned, sanded dull and coated with a bonding primer. Latex put straight onto old oil enamel peels off in sheets.
Old oil-based paint is common on doors, trim and cabinets in older local homes. New oil-based paint is not. The South Coast Air Quality Management District limits the solvent content of paint sold here under its Rule 1113, so nearly everything on the shelf is now water-based.
Do bare drywall patches need primer?
Yes. Bare drywall patches need primer every time. Joint compound soaks up paint differently from the painted wall around it. Without primer the patch shows as a dull, flat spot that you can see from across the room. Spot prime each patch, and on textured walls match the texture before priming.
Good prep is written into our quotes. Call or text (909) 487-2695 for a free estimate.