In a recent video on the Trusted House Painter channel I sat down with Jacey from Benjamin Moore to talk through a real-world problem: a kitchen ceiling under a deep skylight with paint that was blistering, flaking and alligatored from moisture. If you’ve ever had paint fail above a sink or under a skylight, this is the exact situation we addressed — and the primer/paint combo we agreed on is what I now recommend for high-moisture ceilings and skylights.
The problem: paint failure around skylights and wet ceilings
Here’s the scene: an island with two big sinks sits under a deep skylight. The ceiling paint around that skylight is cracking, blistering and flaking — classic moisture-related failure. Before you reach for a paintbrush, you need to understand two things: the right surface prep, and the right primer/paint system for high moisture environments.
Prep: what I do first
Proper prep is the foundation of a lasting paint job. On this skylight ceiling I recommended the following steps:
- Scrape loose and flaking paint thoroughly.
- Sand the remaining edges to feather and smooth the surface.
- Skim any chipped edging or gouges with joint compound (drywall mud), let dry, then sand to a smooth finish.
- Caulk the bead where the skylight frame meets the ceiling — Jacey noted this is a common failure point and worth sealing.
Primer choice: when oil beats acrylic
My go-to in many situations is an acrylic-latex multipurpose primer (for example, Zinsser 1-2-3). But where there’s significant moisture present — like around skylights, wet rooms, or over sink islands — Jacey and I agreed an oil-based primer is the safer bet to establish a strong, moisture-resistant foundation.
“Any time that I’m coming across a lot of moisture it just screams oil to me.”
For this job she recommended Prime Lock by Insulax, available at Benjamin Moore stores. A few practical notes about that product from our conversation:
- It’s an oil-based, multi-purpose primer formulated for difficult substrates and high-moisture situations.
- Expect an oil-type odor — even “low‑odor” oil primers can smell. Proper ventilation helps.
- Compared to some traditional oil primers (for example, Zinsser Cover Stain), Prime Lock has less VOCs and higher volume solids — which means more material stays on the surface after solvents evaporate.
- It bonds over drywall, patched compound, and existing paint layers — making it suitable to prime after your skim/sand work.
Should you apply two coats of primer?
Generally, one solid coat of a high-quality oil primer is sufficient. However, Jacey recommended using your judgment once you’re up at the skylight — if the surface still feels especially porous or you sense high moisture at the substrate, applying a second primer coat while you’re up there is a small investment of time that can pay off in durability.
Dry time before painting
For Prime Lock (and similar oil primers) you should generally wait at least 2–4 hours before applying topcoat. That window depends on environment: high humidity, limited airflow, or cooler temperatures can extend tackiness and require more drying time. Check the surface and don’t rush the topcoat — proper cure time is important.
Topcoat: Aura Bath & Spa — why it’s the recommendation
For the actual paint Jacey recommended Benjamin Moore Aura Bath & Spa. Key reasons:
- It’s formulated specifically for high-moisture areas like bathrooms and wet rooms.
- It contains mildewcides and fungicides to resist mildew growth.
- It only comes in a matte finish — useful for ceilings where you want low reflection and a uniform appearance.
- It’s a higher-end product, so you’ll get better durability, color development, and a truer-looking white (or whatever color you choose) than with cheaper flat ceiling latex paints.
In short, Aura Bath & Spa gives you a finish that handles moisture better and resists the mildew issues that often cause repeat failures under skylights or over sinks.
Step-by-step recap
- Scrape away loose paint and sand the perimeter.
- Skim patched areas with drywall mud, let dry, sand smooth.
- Caulk the bead where the skylight meets the ceiling to stop moisture intrusion at that joint.
- Prime with an oil-based primer — Prime Lock (Insulax) — especially for high moisture. Consider a second coat if the substrate looks compromised.
- Allow primer to dry (typically 2–4 hours; longer in high humidity), then topcoat with Benjamin Moore Aura Bath & Spa (matte).
When to choose oil primer over acrylic
Modern acrylic primers and paints have come a long way, and for many interior projects they perform very well. But when you’re dealing with persistent or heavy moisture — skylights, wet ceilings, areas near sinks, or poorly ventilated spaces — an oil-based primer is often the most reliable choice to block whatever is driving the paint failure and to provide a harder, moisture-tolerant base.
Final thoughts
If your skylight or damp ceiling is failing, don’t skip the prep and don’t assume a standard interior matte will fix it. The combination we discussed — proper scraping, patching and sealing, an oil-based primer like Prime Lock, followed by Aura Bath & Spa — is a practical, professional solution for long-term performance in high-moisture overhead areas.
If you’re unsure about the underlying moisture source (roof leakage, flashing failure, condensation issues), address that first — paint solves the symptom, not the source. And if you’d rather have a pro handle the assessment and repairs, Trusted House Painter can connect you with local painters experienced in these exact problems.
