Corrosion inside Garage.

[Dave Gilstrap]

Yesterday all the metal inside of the detached garage of the home I inspected was corroded and rusting. The inside of the garage door was rusting as well as the rails, spring and the opener. The foundation bolts and washers were rusted and almost every nail head I saw, even the hinges of the door. What could cause this? Cooking Drugs or storage of caustic chemicals?

[Bruce Ramsey]

Lots of potential causes...

How near the coast is the property?
Any pool chemicals or fertilizers stored?
Whats the age of the building?
Whats the drainage like? Gutters, grading, etc.

[Dave Gilstrap]

We are located inland in the foothills of the Sierras. The Garage looks fairly new 5-6 years old and there is no drainage problems. There is a pool and spa on the property, and it is well landscaped. It could be from storing pool chemicals and fertilizers.

[Ian Page]

Dave,

I'm familiar with Rescue - lived near there for a time a few years ago. The corrosion certainly looks like some kind of chemical reaction with vapors rising into the roof structure. Would the acreage the property sits on support the need for large amounts of fertilizer - though I doubt fertilizer is the cause. Pool chemicals, possibly, but those too would have to be in abundance and open to the environment. Was there any kind of staining on the floor?

I certainly wouldn't rule out something been 'cooked' in the garage but not deep frying the Thanksgiving turkey.

[H.G. Watson, Sr.]

Obviously that plate splice, hold down, and damaged stud upon same, are wrong. Thus suspect other errors, including materials & short cuts, including not set in the pour.

I wouldn't make a leap to cook-lab, as similar can occur without such activity.

First thing that occurs is use of wrong type of pressure treated lumber sills, door framing + nightime condensation + well sealed garage without air exchange + higher temperatures during day, failure to use SS fasteners, rods, bolts, etc. I do not see evidence of an isolation membrane under the sill.

No or damaged isolation/vapor barrier under slab.

Add just a little more salts, amonium, aluminum, hypochlorite, soda ash, lime, lye, into the environmental "mix" and things can speed up expedentially in a closed terrarium-like environment of a closed garage. .

Additionally washing machine/dryer in garage; or laundry, bathroom, or cooking venting into garage. Copper source above, ex. treated 3-tabs, etc.

Storage of batteries excessive heat, might also investigate drywall between living area & garage for chinese origin, and sufficiency of grounding system (ring, rods) for soil type; and proximity to utilities distribution, pipelines, (stray current i.e. cathodic protection systems for same), soil contamination, etc. that may be effecting the "environment" inside, under, and outside this 6/7 y.o. garage.

Use of salts (i.e. epsom salts, fertilizer pellets) on lawn or to be disolved in sprinkler system, I'm trying to remember some product used out West, starts with an "R" 'Revive', 'Renew', something like that, with "wetting agents" used to increase soil water absorption for hardpan or sandy soils and to decrease amount of water used, sprayed on lawn or granuels spread, near bushes & trees; and just be watered in well, but can't recall the name exactly, claims to be 'organic' sourced fertilizer, (chicken poop IIRC) full of iron, surfactants, etc.

Use of 'natural' orange oil based degreasers/detergents or similar on the garage floor...

Point being there are a lot of possibilities on contributing factors, fastener integrity, metals corrosion, etc; safety of structure and health are a concern consult environmental engineer and a structural one.

The simplest suspect would be the treated lumber type and sprinkler hitting the front corner, garage door, and front sidewall of the garage, dissimilar metals - corrosion ex. copper (treated lumber) - zinc - steel. galvanic scale.

[Stephen G]

Could Chinese drywall be considered?

[Jack Feldmann]

I didn't see any drywall in the photos.

[Stephen G]

I was looking at the fourth pic, which I now see as the door, never mind...

[Dave Gilstrap]

Thank H.G. I beieve this garage was built as a storage facility detached from the home and it does not appear to be large enough for a car to fit inside. Golf cart maybe. The summers here are very hot and dry. With all of the extensive landscaping at this home, I believe the storage of fertilizers and other garden and pool chemicals weres probably why The metal corroded.

[Robert Ernst]

I've seen something similar to this from using Muriatic Acid to clean the concrete floors.