Overlooked health hazard

LINDSAY MAST, HOST: Today is Wednesday, April 24th. Thank you for turning to WORLD Radio to help start your day. Good morning. I’m Lindsay Mast.

MARY REICHARD, HOST: And I’m Mary Reichard. Coming next on The World and Everything in It: Mold and where it grows.

Now, if your home is anything like the majority of homes, you probably have mold growing somewhere, and not just in your fridge.

MAST: Mold eats the materials from which our homes are built. That’s a problem for our houses, and also for our health. Mold experts focus on getting rid of mold already in place, making sure it doesn’t get a foothold.

WORLD Correspondent Amy Lewis met a mold expert in Australia.

AMY LEWIS: Tim Law passes rolls of carpet on the front lawn and meets Peter and Faye Ridley outside their ranch house in the hills outside Melbourne.

TIM LAW: My job here is to do an assessment of the damage and if there's any mold. Yeah, yeah. [FAYE] (Carpets have gone up) That's a good thing. Yeah, I do not need to see wet carpets. Get them out.

Inside he’s welcomed by the continuous drone of five dehumidifiers. There used to be ten.

The Ridleys built their house soon after they were married 57 years ago. How a house is built can affect how it withstands moisture. In the Ridleys’ case, a lot of moisture.

A month ago, a heavy rainstorm lodged debris between a shed and a trailer parked uphill from the Ridleys’ house. The makeshift dam broke in the middle of the night. All the water flowed into the Ridley’s house and flooded most of it.

FAYE RIDLEY: I woke up on a Monday morning and I could hear the mop and bucket and I wondered why’s he washing the floor at this hour in the morning?

Tim Law is an architectural scientist. He studies why buildings harbor mold. He also evaluates “events”—burst hoses or one-time floodings. In Australia, the insurance company settles the claim by hiring people to fix the specific event’s effects. Law needs to figure out what those are.

Peter Ridley was the first witness on the scene.

PETER RIDLEY: It drains probably the top of the hillside. It's probably 100 acres up there, that all come down, blocked, and came over, came down through my bush (Right) and just came straight through here.

Once he knows the extent of the flooding, Law knows what gear he’ll need.

AUDIO: [Rustling in bag]

He comes back with his version of a doctor’s bag ready for a house call. It’s a large duffle bag packed with high tech tools zipped into insulated black pouches.

But the tools he uses most frequently?

LAW: This is my favorite. It’s just a torchlight!

….and a measuring tape.

After he gets a layout of the house, he pulls out tools calibrated to detect moisture in different types of materials. Like tile and carpet…

LAW: What I’m doing now is taking a dry reference. I’m looking at an area that’s not affected.

He tests wood and drywall.

LAW: Here’s another one of my tools I really like. It’s calibrated just for timber.

He says his job is part technical and part people skills. Throughout each visit Law takes time to tell the homeowners what he’s doing and why.

LAW: It's a bit of an x-ray at the same time because the timber has a different temperature from the air. Timber has more mass so it moves in temperature more slowly than air. So as the air warms up, the timber stays cool….

Law is really good at finding mold because he knows where it likes to hide.

LAW: We’ll pull out the lower part of the wall, so that we can actually dry it out properly. Because we can run the dryers for a month and the inside of the cavity can still be wet.

But he’d rather not find it anywhere. Renters suffer in the current housing crisis. But even new homeowners are at risk. Their house may be built completely to code—but with wood left out in the rain or with the kitchen and bath vented into a closed attic space, the new homeowner has no recourse.

LAW: There is a sense of social injustice when these things fall between the cracks and nothing can be done about it.

So Law studies why Australia’s houses keep growing the fungi—and how it affects the people who have to live with it.

LAW: Part of it is that I am very intrigued by complex issues. And I think mold is one of those complex issues that overlap three large categories that don't typically overlap. That's the architectural part of it, there is the microbiology. And there's also human health.

Law advocates for victims and for changes to the building codes. In October he spoke to builders at a construction and waterproofing conference in Melbourne.

LAW: When we fail, homeowners get hurt. When we allow ourselves to get carried away with cost-cutting, homeowners pay the price.

The Ridleys endured an event and not a building defect. But both can produce mold within two days.

Law says God mercifully showed the Israelites in the book of Leviticus how to deal with mold. He commanded the Israelites to burn moldy things.

LAW: So that's 4000 years ago, these people already knew that you shouldn't be living in a moldy building. So, some of these things were clear, but in Australia, people see mold and say ‘She'll be right.’

But it won’t be all right without changes. And that’s why Tim Law keeps working on both ends of the problem.

LAW: This is more widespread than people are aware of. So many people are living inside moldy buildings, but not realizing that it has a profound impact on their health.

Reporting for WORLD, I’m Amy Lewis in Monbulk, Australia.

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