Prep is most of a paint job. In the Bronx it is also where old buildings show their age: plaster cracks, stains from the apartment above, steam damage near radiators and many coats of old paint.
Do I need to prime before painting?
You need primer on bare surfaces, on patches, on stains and when changing between very different colors or paint types. You do not need to prime a clean, sound painted wall that is getting a similar color.
- Bare plaster, drywall, wood or metal.
- Patched and skim coated areas.
- Water, smoke, rust or marker stains.
- Glossy or oil based paint that is getting a water based coat.
- A strong color change.
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 bonded. Yes, you can paint over the old paint, and most repaints are exactly that.
The test is adhesion. Press tape on the wall and pull it off. If old paint comes with it, the surface needs more than a new coat.
Do I need to sand the walls before painting?
Walls need a light sand where they are glossy, rough or patched. A flat, clean wall in good shape may only need washing.
One caution for the Bronx. In a building from before 1978, old layers may contain lead. Dry sanding and dry scraping old paint spread lead dust. In those buildings sanding is limited to new patching compound, or done wet or with a vacuum attached sander.
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.
Larger repairs are priced as their own line: wide plaster cracks, loose or bulging plaster, holes and damaged corners. Plaster cracks that come back each winter need mesh tape and setting compound, not just a skim of filler.
How do I paint over a water stain so it does not bleed through?
Seal the water stain with a stain blocking primer first, then paint. Ordinary wall paint lets the stain bleed back through, sometimes within days.
Fix the leak before anything else. In an apartment the water often comes from the bathroom or radiator above, so the super or the neighbor has to be involved. The plaster must be dry before it is primed.
Can you paint over smoke stains or pet smells?
Yes, with the right primer. Smoke residue from cigarettes or a fire has to be washed off, then sealed with a stain and odor blocking primer.
Paint alone does not stop a smell. If the odor is in the floor, the carpet or inside the walls, sealing the painted surfaces will only help in part.
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 cleaned off, the surface dried and primed, and the cause dealt with.
Many Bronx bathrooms have no fan and a small window or none. Steam has nowhere to go. A mildew resistant bathroom paint helps, and so does leaving the door open after a shower. A patch larger than a few square feet, or mold that returns fast, points to a leak and is a job for the building or a mold specialist.
Paint is peeling to bare wood on an old house. What prep does it need?
Scrape off everything loose, feather the edges, prime the bare wood the same day and caulk open joints before the finish coats.
On a house built before 1978, assume the old paint has lead. Scraping is then done wet over ground sheets, with the chips collected, and no open flame or dry power sanding.
Why is my paint peeling?
Paint is peeling because something broke its bond to the surface, and the cause is nearly always moisture, a dirty or glossy surface, or a weak layer underneath.
- Moisture from a leak, steam or damp masonry.
- New paint over grease, dust or soap film.
- Water based paint over glossy oil paint with no primer.
- Old calcimine or chalky paint on a ceiling that no modern paint sticks to.
- Too many coats, built up until their weight pulls the oldest layer off.
Why is paint bubbling or peeling in my kitchen or bathroom?
Paint bubbles and blisters in kitchens and bathrooms because of steam and grease. Moisture gets behind the paint film and pushes it off.
The cure is to remove the loose paint, clean, prime with a moisture tolerant primer and finish with a paint made for wet rooms. Then get the steam out with a fan or an open window.
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. Latex softens and comes off on the rag. Oil based paint does not.
Latex can go over oil, but only after the oil paint is cleaned, dulled and primed with a bonding primer. Skipped, the new coat peels off in sheets. Old trim, doors and bathrooms in Bronx buildings are very often oil based.
Do bare drywall patches need primer?
Yes. Bare drywall patches and joint compound need primer before paint. Without it the patch soaks up paint differently and shows as a dull or shiny spot.
The same goes for plaster repairs. New plaster and setting compound must be fully dry and primed before the finish coat.
What is calcimine and why does ceiling paint fall off?
Calcimine is an old chalk based ceiling paint used in many pre-war buildings. Modern paint will not stay on it, so the new coat peels in large flakes.
The fix is to wash or scrape it off, or to seal it with a primer made for calcimine. A painter who has worked in old New York buildings will test for it before painting a ceiling.
Questions about your own walls? Call or text (718) 866-3263.