Prep is most of a paint job. Paint only sticks to a surface that is clean, dull, dry and sound, and most early failures come from skipping one of those four. Our quotes include patching, sanding, caulking and priming.
Do I need to prime before painting?
You need primer on anything bare, stained, glossy or patched. That means new drywall, bare wood, joint compound, metal, water or smoke stains and slick old enamel.
Primer does jobs that paint cannot: it seals porous surfaces, grips slick ones and blocks stains. Paint sold as paint and primer in one is thicker paint. It is fine over sound, clean, painted walls, but it does not replace a real primer on problem surfaces.
Do I need primer if the old paint is in good shape, and can you paint over old paint?
No primer is needed over old paint that is clean, dull and well stuck, and yes, you can paint straight over it. Two finish coats on a washed wall is the normal repaint.
Prime first when the old paint is glossy, oil-based, chalky, a much darker color or patched in many places.
Do I need to sand the walls before painting?
Walls in good shape need only a light sand to knock down bumps and dull any shine, not a full sanding. Patches, glossy trim, doors and cabinets do need proper sanding.
Textured walls, which most valley homes have, are not sanded flat. They are cleaned and the repairs are textured to match. In a home built before 1978, sanding old paint can release lead dust and must follow lead-safe rules.
Do painters fix nail holes, cracks and dents first?
Yes. Filling nail holes, small cracks and dents is part of normal prep, and it is in our quotes. Larger holes, loose tape and damaged corners are drywall repair and are listed separately.
Nail pops and seam cracks are common here. Framing dries and shrinks through our long heating season and the fasteners back out. A pop is re-fixed with a screw beside it, then filled, sanded and primed.
How do I paint over a water stain so it does not bleed through?
Seal it with a stain-blocking primer first. Water stains come straight through ordinary latex paint, even after three coats.
Fix the leak before anything else and let the area dry. Ceiling stains in spring are often from ice at the eaves or a roof leak during snow melt. If the drywall is soft or sagging, it is replaced, not painted.
Can you paint over smoke stains or pet smells?
Yes, with the right sealer. Smoke residue from cigarettes, a fireplace or a kitchen fire has to be washed off, and then the surface is sealed with a stain and odor blocking primer before paint.
Pet odor in walls and trim is sealed the same way. Odor in the subfloor or carpet pad is not a paint problem and needs its own fix.
Mold on the bathroom ceiling: can it just be painted over?
No. Mold painted over grows back through the new paint. It has to be killed and cleaned off, the surface dried and primed, and then painted with a bathroom paint that resists mildew.
Our air is dry, so bathroom mold here almost always means a weak or unused fan. Run the fan during a shower and for a while after. For a large area, HomeGuide lists professional mold removal in a bathroom at $500 to $2,000 nationally. Mold that keeps returning, or covers a wide area, needs a specialist.
Paint is peeling to bare wood on my old house. What prep does it need?
Every loose edge has to be scraped back to paint that is firmly stuck, the edges sanded smooth, the bare wood primed and the joints caulked. Then two finish coats go on.
Bare wood that has greyed in the sun must be sanded to fresh wood, or the primer will not hold. On a house built before 1978, assume the old paint has lead until a test says otherwise. Scraping and sanding then follow lead-safe work rules.
Why is my paint peeling?
Paint is peeling because something got between it and the surface: moisture, dirt, chalk, gloss or a coat that was itself loose.
- Outside: water behind the paint from open joints, sprinklers, snow against the wall or failed caulk.
- Sun: south and west walls at this altitude get brittle and crack, then water gets in.
- Inside: steam in bathrooms and kitchens, or latex put over oil-based paint without primer.
- Anywhere: paint put over dust, grease or chalk.
The cause has to be fixed along with the paint, or it peels again in the same place.
Why is paint bubbling or peeling in my kitchen or bathroom?
Bubbling and blistering in a kitchen or bathroom come from moisture and from poor bonding. Steam gets behind a weak coat and lifts it.
The fix is to scrape the loose paint, sand, prime with a bonding primer and repaint with a washable finish made for wet rooms. Better airflow stops it coming back.
How do I know if old paint is oil or latex, and can latex go over oil?
Rub a hidden spot with a rag wet with rubbing alcohol. Latex softens and comes off on the rag. Oil-based paint does not.
Latex can go over oil-based paint only after the surface is cleaned, sanded dull and primed with a bonding primer. Skip that and the new paint peels off in sheets. Old trim and doors in homes built before the 1990s are often oil-based.
Do bare drywall patches need primer?
Yes. Bare drywall patches and joint compound must be primed before paint. Unprimed compound soaks up the paint and shows as a dull, flat patch through the finish coat.
That is called flashing. A coat of primer over each patch, and often over the whole wall, evens it out. See our page on wallpaper, popcorn ceilings and drywall for more.