Wet-bulb hours at the Des Moines station
For Des Moines, about 30 miles south of Ames, NOAA counts in an average year about 413 hours with the wet-bulb temperature above 73°F and about 1,291 hours above 67°F. These are counts for the Des Moines station, not readings taken in Ames.
A note from Ames history
The Ames water utility was formed in 1891; its old water treatment plant was built in 1927 as a two-million-gallon-a-day iron removal facility and was later expanded to include lime softening.
Growth follows water
Spores turn up in ordinary dust indoors and out. They can settle on the paper face of drywall, on wood, on carpet backing, on stored cardboard and on the dust film over almost any surface. What lets them form a colony is a material that stays damp. Dry that material and growth can stall; leave it wet and a patch may keep spreading behind paint, under flooring or inside a wall cavity where nobody looks.
So the leak deserves more of your attention than the stain. When you call a company, ask how it plans to find the moisture source, who will stop it, and how the structure will be shown to be dry before anyone removes or cleans the growth. A plan that starts with a pry bar and can't name a cause leaves out the step everything else depends on.
What the position of a damp spot can suggest
Where a patch sits is a clue, not a diagnosis. Use it to decide whom to call first.
On a ceiling
With a bathroom, laundry room or attic air handler overhead, the water may come from a drain joint, a supply line, a toilet seal, a shower pan or a condensate line. With an attic overhead, look at the roof deck around vents, the chimney and any valleys, and find out where the bath fan duct ends.
Low on an outside wall, or in a basement
Water can arrive from the soil side. During a rain, watch where the downspouts let go and which way the ground beside the foundation slopes. Below grade, look for damp masonry, a white crust on concrete or block, and tide marks along the base of the walls.
Around a window or exterior door
Cracked caulk, a split sill or flashing that no longer sheds rain can let water into the framing below the opening. Press the drywall under the sill and look closely at the lower corners of the frame.
Inside a cabinet or behind an appliance
The floor of a sink base, the space behind a dishwasher and the wall behind a refrigerator with an ice maker line can stay wet from a slow drip that doesn't show in the room.
In a closet, or behind furniture on an outside wall
Still air against a cold surface can let indoor moisture condense. Ask whether airflow, insulation or indoor humidity is the cause before anyone treats the spot as a leak.
Simple ways to log moisture yourself
An inexpensive hygrometer shows indoor relative humidity at a glance; one in a basement and one in a main room let you compare the two. A moisture meter, yours or a contractor's, shows whether a stained piece of drywall or a sill plate is still wet. Write each reading down with the date and the spot. A short log like that gives a remediation company something firmer than a memory, and it can show later whether the drying held.
What to ask a proposal to cover
Ask each company to put the whole job in writing. The document should say where the growth is, how far it appears to reach and which moisture source fed it. Ask how the work area will be closed off from the rest of the house, how people will get in and out, and how a filtered air machine will hold that area at negative pressure. Ask which porous materials, such as drywall, insulation and carpet, are coming out, and how they will be bagged before they travel through your rooms. Ask how framing and subfloor that stay in place will be cleaned and dried, what moisture target the plan sets, how often readings will be logged, and what you will be shown before anything is closed up.
Ask, too, whether the person sizing up the growth is separate from the company that will remove it. When one firm both measures the problem and does the work, it may be deciding the size of its own job.
If you look before anyone arrives
Lifting a carpet corner or a ceiling tile can stir spores into the air. Wear gloves, eye protection and a well-fitting disposable respirator, and keep children and pets out of the room. Leave dry growth unscrubbed and keep fans from blowing across it. Anyone with health questions about mold should take them to their own doctor.
Questions to put to every company
- What do you think is feeding this growth, and which trade repairs that before cleanup?
- Who writes up the extent of the problem, and is that person on your payroll?
- What state license or registration, if any, covers this work, and what is the number?
- Will your own crew be in my house, or a subcontractor's?
- Can you send proof of liability coverage and workers' compensation before work starts?
- Which readings will tell us the structure is dry, and will I get them on paper?
- What does the report you hand over at the finish contain?
Permits, coverage and the insurer
If the repair means new framing or moved plumbing or wiring, ask which city permits it needs and who will pull them. Call your own insurer before damaged materials are thrown out, and ask what your policy says about mold and about the water damage behind it, which records it wants, and whether an adjuster should see the damage first.
One record from start to finish
Give every bidder the same written description and compare prices for that same work, not for different ideas of the job. From the first phone call, keep photos, the moisture log, reports, bids and receipts together in one folder.