Drywall & Wall Cavity Odor
Drywall Odor Removal — Why Painting Over It Doesn’t Hold
Pet urine in drywall doesn’t stay on the surface — paint over it and the smell comes back. Drywall is paper-faced gypsum; urine wicks up the paper from the floor line, soaks into the gypsum core, and migrates into the wall cavity behind it.
This is what makes drywall odor different from floor odor: it hits you at nose level. We’re not a paint service — we identify which drywall is salvageable and which has to come out, then treat the cavity behind it before anything new goes back up. Our structural odor remediation is backed by a 5-year written guarantee on qualifying work.
- Founded 1989
- Pet Odor Specialists Since 2000
Call now if painting over the smell hasn’t held.
Free Phone Quote · Discreet · No Judgment
If you can smell it, we can find it. If we can find it, we can treat and seal it at the source.
Founded 1989 · Pet Odor Specialists Since 2000
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What best describes your situation?
- The smell is concentrated near walls or in specific rooms
- Cat sprayed on walls, doors, or baseboards over time
- We painted over it and the smell came back through
- Kilz didn’t seal the odor
- Multi-cat household with marking spray on vertical surfaces
- We smell it most when the AC runs or rooms warm up
- Tenant cat damage extended into the drywall, not just the floor
Quick qualifier
This service is for:
- Drywall painted over where the smell still returns
- Cat spray on vertical wall surfaces
- Drywall saturation behind baseboards from years of wicking
Not for:
- Cosmetic stains with no underlying odor
- General drywall repair or patching
- Painting or finishing
What this looks like in a real home
Drywall Odor Removal: the problem, the cause, the fix
01What we findTrace where it wentUV shows where urine hit the floor and climbed the wall behind furniture and trim. 
02Behind the trimPull the baseboardThe stain hides behind the baseboard, in the drywall edge and the tack strip. 
03The fixCut out what paint can’t hideSoaked drywall is cut out to clean studs and the sill plate is treated before rebuild.
Illustrative images.
The misdiagnosis
Most people think the smell is in the floor
In many cases it’s in the walls. Homeowners replace carpet, seal the subfloor, install new flooring — and the smell still returns, because urine wicked into the bottom 4–12 inches of drywall over years is still releasing odor at nose level every time heat or humidity changes.
Paint traps it — it doesn’t fix it.
Why drywall holds pet urine
Drywall isn’t a sealed surface — it’s a sponge faced with paper. Two thin paper layers sandwich a porous gypsum core; the paper face wicks liquid into the core, which then has access to the whole wall section.
Floor-line wicking
The bottom 4–12 inches.
Cat spray
Vertical, at nose height, runs down.
Behind baseboards
Pools in the gap and absorbs from behind the trim.
Wall-cavity migration
Reaches insulation, studs, and the sill plate.
Why painting over it fails
Surface coatings bond to a clean, dry, properly prepared surface; a urine-saturated wall isn’t one. The fix isn’t a different paint — it’s preparing the wall properly first, which sometimes means removing it.
Knowing when drywall can be treated vs. when it has to come out is what over 35 years of industry experience, including more than 25 years specializing in structural pet urine odor remediation, tells us.
Real scenarios we handle
Every one is a job we’ve handled. The first is the most common.
- Most common
“We painted twice and the smell still comes back”
Cat-spray vertical contamination
Tenant cat damage into the drywall
Learn moreMulti-cat wall saturation
Behind-baseboard wicking
Learn more
How we treat drywall
- 01
Inspection first
Maps which surfaces are actually contaminated.
- 02
Treat or remove
Treat salvageable drywall in place; remove and replace what can’t be saved; treat the cavity behind it.
- 03
Seal
Seal qualifying surfaces with the Odor Encapsulator — designed to help contain and reduce embedded urine vapors.
- 04
5-year written guarantee
On qualifying work.
The 5-Year Written Guarantee
Qualifying surfaces treated with our proprietary Odor Encapsulator are backed by a written 5-year guarantee, subject to the documented treatment scope and written terms. The Odor Encapsulator is designed to help contain and reduce embedded urine vapors in the materials it is applied to.
It addresses pet-urine odor in the specific structural materials we treat. It does not make the property impervious to future pet accidents or odor from other sources, and it does not apply to inspections, estimates, oxidizer-only treatments, or allergen services.
Start With a Free Phone Quote
Tell us what you're smelling and where. A free phone quote takes under 10 minutes — and we'll point you to the right service, even if it's not ours.