On July 9, the temperature outdoors was a typical summery 88 degrees, with humidity that felt like 700 percent.

In the attic of our Potomac house, though, it was 120 degrees. Crews had been working there for two weeks to remove all the air-conditioning equipment that was filled with brown mold.

As for the temperature in our kitchen and home office, let's just say it was nasty.

Our air conditioning had been shut down since September 2002, when we first noticed the dark brown stuff on a supply register on our bedroom ceiling. It took nine months and more than $25,000 to confirm it was mold, find the causes and get rid of it.

Moisture problems and mold have become more commonplace in homes, and several multi-million-dollar lawsuits have made mold, well, a four-letter word.

What we had in our house was not the relatively rare "killer mold" that has drawn lawyers and hypesters. Instead, it was a common, irritating variety. Still, if such mold is widespread, it can lead to unhealthy conditions that particularly aggravate those with allergies and sinus problems.

Increasing problems with mold may be related to energy conservation efforts. As a former Pepco employee, I thought I knew a lot about energy conservation, but this surprised me. The Energy Department's Office of Energy Efficiency and Renewable Energy, in a fact sheet updated on the Internet in March, said conservation measures and increased energy efficiencies undertaken in recent years could be creating moisture problems in buildings. "Making [houses] very tight, but with poor ventilation can create many indoor air quality problems including mold . . ," the fact sheet says.

The Energy Department said that it is advisable that "tight" homes should have a controlled way to move fresh air into the house and stale air out, while minimizing energy loss. The remedy is to install an array of attic vents. Go figure -- seal it up on the living floors, open it up in the attic.

Some heating, ventilation and air-conditioning (HVAC) contractors say that higher-efficiency air-conditioning systems, mandated by the government in the 1990s, can worsen indoor air quality problems.

Here is why: If you sealed your drafty house and leaky attic and then replaced your older compressor, you probably chose a new unit that was the same size, in tonnage, but more efficient because it uses less electricity. But you may have been able to buy a smaller sized compressor. That was because the lower-tonnage unit, though more efficient, worked harder to reach the desired thermostat temperature, causes the air conditioning to run long enough to remove the humidity in the house. With oversized units, the compressor cools the house quickly, but may shut off after six minutes rather than 15 minutes and thus does not have time to remove the moisture.

American homeowners have fallen for a favorite consumer mantra: bigger is better. The mistaken thinking is, if I receive so much benefit from a 3-ton unit, why not buy the 3.5- or 4-ton unit? In fact, a 2.5-ton unit may have been enough.

Sinus Infections

As much as we wanted to deny our mold problem, health and comfort made us face it. My ear, nose and throat doctor, as well as my allergist, said the mold was contributing to my eight sinus infections in 14 months, all since moving into this house. In addition, all the HVAC vendors who looked at the mold said that it was so thick and widespread in the ducts and air-handling equipment that the air-conditioning system would not last through the summer of 2003. This unwanted guest living in our attic had to get out.

Four years ago, we found a wonderful 27-year house on more than two acres in Potomac. We bought it for below appraisal value knowing it needed renovation work. We gutted the Formica-laden kitchen and put in the requisite granite and Grohe. We moved the foyer staircase and replaced the roof, siding, gutters, landscaping and deck. We painted and reupholstered. With the real estate market booming, our increased equity has more than recovered these expenses.

The HVAC system's two outdoor compressors and two attic air handlers were only three years old when we bought the house. Two years later, both outdoor compressors inexplicably shut down within days of each other -- just weeks shy of the expiration of their five-year warranties. We replaced them, and thought the HVAC infrastructure was good to go.

By the following summer, however, we noticed that the air-conditioning system, which is separate from our baseboard water heating system, was failing. The house air did not feel crisp or dry. That September we discovered the mold. Figuring it was some transient stuff, I cleaned up the bedroom ceiling register with some bleach and water. Within a week, the mold was back.

After examining the mold-filled duct system and air handlers in the attic, one HVAC vendor said we had an upscale house with an HVAC system that belonged in an Arkansas mobile home park.

Looking for mold removal solutions, I drew upon my 20 years experience managing press relations in Pepco's communications department. Until my retirement two years ago, my job included explaining energy conservation measures and promoting air-conditioning rebate programs. I knew more than your average homeowner about air-conditioning systems; I had confidence that along with my husband, a retired PhD engineer, we could pinpoint the problem and fix it, in short order.

Unfortunately, most Washington HVAC contractors do not want to deal with mold. They are concerned about liability because they lack knowledge and resources. And for those in the repair business, mold was not profitable.

Here is what they saw: Mold was thick throughout our main attic ducts and coated the fan blades and circuitry of the air handlers.

We first sought the least-cost solution. We asked each company we could get to return our calls or inspect the house, "Could we just replace or clean the attic air handlers, and patch up the old fiberboard ducts and continue to use them?"

No, we were told. In any case, we needed to know the source of the moisture problem.

Who could answer this and other questions with authority?

Progress slowed over the winter and into spring. First we were snowed in, then our seventh grandchild was born. Over nine months, we consulted 25 vendors. They came with infrared cameras, cowboy hats, business cards, clipboards, training program certificates and four-inch thick notebooks that they admitted not having read.

Each one had an idea, but none would stand behind it. Each told us to contact another expert, but few could give us names with experience and a good reputation.

We heard such comments as:

"I don't know what's causing your moisture and mold. . . . I can replace your equipment but I can't tell you mold won't come back. . . . I can't make any money on this kind of a job; call the duct guys . . . Call the big HVAC guys . . . No, call the remediation companies . . . I don't know any remediation companies who clean up mold . . . I won't touch this until you find out what kind of mold it is and how to remove it . . . Oh, I can fix it; how much do you want to spend?"

Telltale Moisture

After several months of this, Pepco Energy Services referred us to an energy analyst and equipment tester. As an expert-for-hire and former home inspector, he was not selling a product or service, so we thought he had more credibility. His 25-page report with photos detailed a classic case of a leaky, dilapidated system. He also predicted that having our system in the attic would jack up the price of removal of the old and installation of the new.

So, where was the moisture coming from? The analyst questioned the sizes of our compressors because their short cycling left the house clammy. He explained the implications of leaky filters, ducts and air handlers that lost about 20 percent of cooled house air into the attic, while letting in dirt and spores.

The ducts were not steel but cheap fiberglass board, quick to install, impossible to clean and fairly common in the southern states. Fiberboard draws moisture and is an incubator for spores. When the hot attic air hits the cool air-conditioned air through gaps in the uninsulated ducts, condensation forms inside, just as moisture builds up in your air-conditioned car windows on steamy days. At the same time, the filters were too small for their housings, letting unfiltered air pass into the system.

Here were three plausible reasons for the moisture and mold -- an oversized compressor, old leaky ducts and improperly fitting air filters. After all, mold needs food (such as fiberboard ducts or dirt in steel ducts) along with moisture (sucked through the air-conditioning returns into the system and also present from leaky ducts) to grow into nasty mold colonies. How did these conditions get past the HVAC company that serviced our equipment annually? Were they too spooked by potential liabilities to inform us of a major problem?

The energy-inspections expert referred us to cleaning and remediation companies. The first company that came to the house said it would bid on the job only if we hired an internal air quality company. That IAQ hygienist would test the mold and recommend a removal protocol, giving cover to the remediation company.

As we searched for the best companies to do our work, it seemed to us that only recently have the HVAC and cleaning businesses started to build up their expertise. HVAC guys kept telling us they attended "a class" over the winter. And it was only 18 months ago that the primary certification group for the restoration and cleaning industry, the 30-year old, non-profit International Institute of Cleaning and Restoration Contractors, added mold remediation to its certificate training programs. About a half-dozen other associations have similar training and certificate programs.

The $25,000 Solution

If having yucky mold and feeling like a leper were not enough, finding the money for the fix really hurt.

How about filing a home insurance claim? According to a Wall Street Journal article from March, "Mold-related insurance claims reached a record $2.5 billion last year, almost double 2001, and nearly all major insurers are now excluding mold from standard policies."

There is no longer a guarantee that home insurance policies will pay to fix a mold problem that did not result from a single catastrophic event. Many policies are not even paying on one-time events, according to the article. Even if they were to cover some of our removal and replacement costs of more than $25,000, we found that might cause other problems.

The reason is that the insurance industry has come increasingly to rely on a data base of claims-per-address called CLUE, for Comprehensive Loss Underwriting Exchange. How does it work? When you try to sell your home, the new buyer seeks home insurance. A check on CLUE is made on your address to see its claim history. If mold comes up, no other insurance company wants to sell coverage on the tainted house, and no insurance means no mortgage. So your house may not be saleable.

Our mold turned out to be the nontoxic, most-commonplace variety of Cladosporium. It was isolated in our attic air-conditioning ducts and equipment. This mold is an irritant to allergy sufferers and needed to be removed. But it did not grow as a result of leaky water pipes, a wet basement or this past winter's ice dams. Ultimately, we decided that it was better not even to try to recover our costs through our homeowners' insurance, because it would enter our address into the CLUE data base.

The work of the independent consultant and an indoor air quality hygienist led to our signing three contracts -- for remediation, replacement and new attic insulation work. The ducts had to be removed, so a guest bedroom was emptied and converted to a sealed containment room. The work began in July, among the worst months to be without air conditioning.

Our goal was to have a system that would maintain the house's relative humidity at less than 50 percent, a level where mold will not grow. We needed to do many things to attain that goal. And in case the new air handlers and redesigned distribution system didn't stop the mold from returning, we added other technologies to stop the spread of mold. While we did not do all things our experts recommended, we did enough to empty the bank account.

Breath of Fresh Air

Now, our new, squeaky-lean, air-conditioning system is in place and just some fine tuning remains. This nine-month process was mentally exhausting and expensive. When the hot weather kicked in, we experienced time travel to the 1930s -- fans blowing across bowls of ice and the merits of screen doors used for cross ventilation. Eating alfresco was no longer cute. And our tempers seemed to have shorter fuses.

Despite the difficulty of finding the right contractors, we were lucky to be in a region where we at least had choices. We just wish the various segments of the HVAC and indoor air quality business would step up to the task and do the following:

* Inform customers from the get-go of mold problems in the air-conditioning system or its potential.

* Get smart when designing and installing new systems.

* Make referrals to other air quality and remediation experts to handle the various tasks required.

* Improve new construction to accommodate the reality of new humidity build-up problems.

* Recognize the limitations of duct cleaning.

Every house has mold to some extent. If it has dried out and stopped spreading, and is not entering the air stream, we learned it could be left in place. Special paint can be used to contain it. But because our nontoxic mold was in the units that moved the air in our house, we had to deal with this irritant. The improvements we made may not be visible to other people, but we now breathe more easily.

Technician Christopher Wagner checks attic-based air-conditioning equipment.Christopher Wagner of Parker Pearce Service Express installs an new air-conditioning unit at the Moses house.Nancy Moses uses control panel to regulate the temperature and humidity.