Prep decides how a paint job looks and how long it lasts. In Manhattan's older buildings, prep is most of the work.
Price ranges on this page are national figures published by HomeGuide for 2026. They are not our quotes. Manhattan labor rates, building rules, access and the state of your walls move the number up or down. Last checked October 2026.
Do I need to prime before painting?
You need primer on anything bare, stained, glossy or patched. You do not always need it on clean, sound, flat paint in a similar color.
- Bare plaster, drywall, wood and metal.
- Patches and skim coated areas.
- Water, smoke and marker stains.
- Glossy or oil-based old paint.
- A big color change.
Different problems need different primers. A stain blocker is not a bonding primer, and neither is a drywall sealer.
Can you paint over old paint, and do I need primer if it is in good shape?
Yes, you can paint over old paint that is clean, dull and firmly stuck, and often without primer. Two finish coats over sound paint is a normal repaint.
The catch in old apartments is that the paint is rarely all sound. Ten or more layers can build up over a century. Where the layers are cracking or lifting, new paint adds weight and pulls them off. Those areas must be scraped and repaired first.
Do I need to sand the walls before painting?
Walls need a light sand in most cases. It knocks down dust nibs, old roller texture and drips, and it gives glossy paint a tooth for the next coat.
Patches always need sanding, and trim almost always does. In a home built before 1978, dry sanding old paint can release lead dust, so the method matters. See our lead paint page.
How do you prepare old plaster walls?
Old plaster is prepared by opening the cracks, filling and taping them, fixing loose areas and then skim coating where the surface is rough. After sanding, the repairs are primed.
Hairline cracks in plaster tend to come back if they are only filled. Taping them gives a better chance. Nationally, skim coating costs $1.00 to $1.30 per square foot of wall and $1.00 to $1.50 for ceilings.
Do painters fix nail holes, cracks and dents first?
Yes. Filling nail holes, small cracks and dents is part of a normal paint job, and it is in our quotes.
Larger repairs are a separate line: holes from old wiring or plumbing work, failed plaster, or walls damaged by a leak. We point those out at the estimate so the price has no surprises.
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 latex paint will not hold it back. The brown mark comes through again, sometimes within days.
Make sure the leak is fixed and the area is dry before anything else. In an apartment the water often came from the unit above or a riser in the wall, so tell the building. Plaster that stayed wet may be soft and need repair.
Can you paint over smoke stains or pet smells?
Yes, with the right primer. Smoke and nicotine must be washed off as far as possible and then sealed with a stain and odor blocking primer before the finish coats.
Without that primer, yellow stains bleed through new paint and the smell returns in humid weather. Pet odor in walls is treated the same way. Odor in the floor 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 cleaned off, the surface dried and the cause dealt with.
Small patches of surface mildew on a bathroom ceiling are a cleaning and priming job. A large area, or mold that returns, points to a leak or poor ventilation. Nationally, remediation of a small area is listed at $500 to $1,500. Many Manhattan bathrooms have no window, so a working exhaust matters.
Paint is peeling to bare wood on an old building: what prep does it need?
Paint peeling to bare wood needs scraping to a firm edge, sanding, a coat of primer on the bare wood, filling and caulking, and then two finish coats.
Bare wood that has been open to weather for a long time turns grey and will not hold paint until that weak surface is sanded off. On buildings from before 1978, assume the old paint has lead and use lead-safe methods.
Why is my paint peeling?
Paint is peeling because it has lost its grip on what is under it. The usual causes are moisture, a dirty or glossy surface, latex over oil paint without primer, or too many old layers.
Look at the back of a peeled chip. If it carries many layers, the oldest coat let go. If it is one clean layer, the newest paint never bonded.
Why is paint bubbling or peeling in my kitchen or bathroom?
Paint bubbles and blisters in kitchens and bathrooms because of steam and moisture. Water vapor gets behind the paint film and pushes it off.
The fix is to scrape and repair the area, prime it and use a paint made for humid rooms. Running the fan and leaving the door open after showers does as much as the paint does. Bubbling in one spot on a ceiling can also mean a leak from above.
How do I know if old paint is oil or latex, and can latex go over oil?
Rub the paint with a rag and a little rubbing alcohol. Latex softens and comes off on the rag. Oil-based paint does not.
Latex can go over oil only after sanding and a bonding primer. Skip that and the new paint peels off in sheets. Doors and trim in pre-war apartments are very often oil paint under the top coat.
Do bare drywall patches need primer?
Yes. Bare drywall patches and joint compound need primer before paint. They soak up paint differently from the wall around them.
An unprimed patch shows through the finish as a dull or shiny shape, a fault painters call flashing. Priming the patch, and often the whole wall, gives an even sheen.
How do you paint radiators and steam pipes?
Radiators and steam pipes are painted cold, after loose paint and rust are removed and bare metal is primed. They get hot enough in winter to affect ordinary paint, so the product should be rated for the heat.
Thick old paint on a radiator is very likely to contain lead in an older building. It should not be dry scraped or heated off.
A free estimate with a written quote is the only way to get a real price for your job. Call or text (917) 970-7431.