Painting — FAQ
Why can't I use regular primer in my bathroom?
Standard primers lack moisture-barrier resins that prevent steam penetration. Without damp-seal technology, paint peels within 6-12 months in high-humidity conditions. Bathroom-specific primers contain antimicrobial additives that inhibit mold growth behind paint layers.
How many coats of primer does a bathroom need?
One coat suffices for new drywall or light stains. Two coats required for heavy water damage, smoke stains, or dramatic color changes. Always apply second coat within 24 hours for proper chemical bonding between layers.
Can I paint directly over bathroom primer?
Yes, after 1-2 hour dry time. We recommend painting within 7 days for optimal adhesion. Beyond that, primer surface collects dust and loses tack—lightly sand with 220-grit paper and wipe clean before painting.
What's the difference between primer and primer-sealer?
Primer-sealers like Hemway include damproofing agents that block moisture vapor transmission. Standard primers only improve paint adhesion. In bathrooms, the sealer component prevents blistering and extends paint life by 3-5 years.
Do I need to prime over existing bathroom paint?
Prime if existing paint is glossy, peeling, or stained. For sound flat paint in good condition, clean thoroughly and paint directly. Test adhesion by pressing tape firmly—if paint pulls off, prime first.
How long does bathroom primer last unopened?
Most primers last 24 months unopened if stored at 10-30°C. Freeze-thaw cycles ruin emulsion primers. Check for lumps or foul odor before using old product—separation is normal, but chunks indicate spoilage.
