Mouse Droppings Cleared From an Encapsulated Crawl Space in Greenwich
1 / 10The inspection on September 11. Droppings across the liner next to one of the homeowner's traps.
See How the Work Was Done
Real photos from this Greenwich job: the droppings on the liner at the inspection, the chewed foam board, the stored contents before they came out, the HEPA scrubber on the cleaned floor, and the crawl space handed back.
Experience has been very professional and responsive. Marvin and his team did an AMAZING job on our project. We're going to have them come back and do a deep clean on our attic space as well.
What Happened
An encapsulated crawl space is a clean, bright, sealed space, which is exactly why this one made the problem easy to see. The homeowner called in September about mouse droppings and an odor in the lower level. At the inspection on September 11 the droppings were everywhere the mice had travelled: scattered across the white liner, piled along the foam board at the foundation wall where it had been chewed through, in and around the storage bins and the boxes of holiday decorations, on the floor registers, and in the finished area by the work bench and the pantry that opens off the crawl space.
There were dead mice in the homeowner's traps and nesting material behind the stored contents. The scope that came out of that walk through was a cleaning scope, and it was written to cover the whole 840 square feet rather than the spots where the evidence was thickest, because droppings do not stay where they land and a crawl space shares its air with the rooms above. The crew was on site on October 12 and 13.
A 120 square foot containment with a decontamination chamber and a zipper door went up between the crawl space and the finished lower level, and two HEPA negative air scrubbers ran for 24 hour periods so nothing disturbed inside the work area reached the pantry or the rooms upstairs. Every stored item came out of the crawl space first, the contaminated contents went into a 12 yard dumpster, and the dead animals and nesting were bagged with them.
Then the ceiling, the walls and the liner floor, plus the finished areas by the work bench and the pantry, were HEPA vacuumed in detail, wet wiped with a bio cleaner and disinfected, and fogged with a plant based antimicrobial through a cold ULV fogger to reach the gaps a wipe cannot. The bins that were worth keeping were cleaned and set back on the liner. It is worth being clear about what this job was not. No entry points were sealed and no trapping was sold; the traps in the photos belong to the homeowner. The liner and the dehumidifier in the crawl space were already there.
The foam board that the mice had chewed stayed in place. Cleaning takes out what is there now. Keeping the mice out is a separate conversation with a pest control company, and it should happen before anything new goes back into that space.
Scope of Damage
Crawl Space Floor and Liner
SevereDroppings scattered across the encapsulation liner and piled along the chewed foam board at the foundation wall. The full 840 square feet was HEPA vacuumed, bio cleaned and fogged rather than spot cleaned.
Stored Contents
SevereBoxes and bins of stored items with droppings in and around them, and nesting material behind them. Everything came out; contaminated contents went into the dumpster and the rest was cleaned and reset.
Finished Areas by the Work Bench and Pantry
ModerateDroppings had tracked out of the crawl space into the finished lower level. Those areas were included in the HEPA vacuuming and bio cleaning so the problem was not left at the door.
Floor Registers
ModerateDroppings on the supply registers that feed the rooms above. Cleaned as part of the detailed vacuuming, which is why a crawl space problem is an air quality problem for the whole house.
How We Solved It
- 1
Contain the Crawl Space from the Finished Level
120 square feet of containment with a decontamination chamber and a zipper access door, built between the crawl space and the finished lower level before anything was disturbed.
- 2
Negative Air for Two 24 Hour Periods
HEPA negative air scrubbers held the work area under negative pressure for two 24 hour periods, so dust from dried droppings exhausted through a filter instead of reaching the pantry or the rooms above.
- 3
Contents Out, Carcasses and Nesting Bagged
Every stored item came out of the crawl space. Contaminated contents, the dead animals and the nesting material went into a 12 yard dumpster. Items worth keeping were cleaned and reset afterwards.
- 4
Detailed HEPA Vacuum, Not a Broom
840 square feet of ceiling, walls and liner floor, plus the finished areas by the work bench and the pantry, vacuumed in detail. Dried droppings break up easily and sweeping puts them into the air.
- 5
Wet Wipe, Disinfect and Fog
The same 840 square feet wet wiped with a bio cleaner and disinfected, then fogged with a plant based antimicrobial through a cold ULV fogger to reach the gaps behind pipes and ducts that a wipe cannot.
Tools & Equipment Used
Questions Homeowners Ask
How did mice get into an encapsulated crawl space?
Encapsulation seals the crawl space against ground moisture, not against animals. A liner, sealed walls and a dehumidifier do nothing to close a gap at the sill, a vent or a utility penetration. On this Greenwich home the mice were living on top of the liner and had chewed through the foam board at the foundation wall.
Why clean 840 square feet when the droppings were worst in a few spots?
Because the mice travelled the whole space, and droppings dry, break up and move. The floor registers and the finished area by the pantry showed how far the material had already gone. A spot clean leaves the rest of the floor carrying the same contamination at a lower density.
What happened to the stored boxes and bins?
Everything came out of the crawl space first. Contents the mice had been through went into the 12 yard dumpster with the nesting and the dead animals. Bins that could be cleaned were wiped down and reset on the liner once the space was finished.
Why run negative air and build containment for a cleanup?
Dried droppings turn to dust the moment they are disturbed, and a crawl space shares air with the rooms above through the floor registers and every gap in the subfloor. A 120 square foot containment with a decontamination chamber and two 24 hour negative air periods kept that dust inside the work area and sent it out through a HEPA filter.
Does this stop the mice from coming back?
No. This was a cleaning scope. No entry points were sealed and no trapping was sold; the traps in the photos are the homeowner's. Keeping mice out is pest control work, and it should be done before anything is stored in the crawl space again.
Do you serve Greenwich and Fairfield County?
Yes. Green Restoration serves Greenwich, Old Greenwich, Cos Cob, Riverside and Byram for crawl space cleaning, rodent contamination cleanup, mold remediation and water damage. Our crews are IICRC certified, licensed and insured, and BBB A+ Rated. Call (203) 951-9125 for a free estimate.
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