Unfortunately, mold is also a growing health concern for a sizable portion of the population. My family got severely ill from a moldy house, and it is taking us years to fully recover. The longer we have been aware the more and more folks we find are dealing with something similar.
The EPA Guide is a great start, but in our experience lacks some situational nuance that might increase its helpfulness. Each person reacts differently mold, some folks are just more sensitive than others. There are no federal standards for mold, either for allowable amounts in your home or guidelines for construction. So depending on your health response you may in fact need to go crazy tearing apart your house to hunt for mold.
After talking with ~30 different mold remediators, inspectors, remodeling contractors, etc. We got ~30 different responses for possible causes for mold in our our home. Ultimately, the cost to fix the true sources of mold in our home (due the sources being related to construction practices around the foundation) was equivalent to new construction. We ended up tearing down the moldy house. We're hoping to move into our new house late next spring!
If you need supreme indoor air quality, that'd take the following:
- A fairly air tight building envelope - Proper WRB and insulation strategy (exterior+interior in many places) for your climate (including basement) to prevent condensation - Adequate continuous ventilation/filtration
Which is not feasible for most housing stock in the USA. You might be able to keep the framing, plumping/electrical, and foundation (if you're lucky). Framing is relatively cheap compared to the rest of the house.
We ended up with the realization that the rental housing stock in the Bay Area are all very old, usually not well maintained and depending on the area, very likely to have or have had water damage, the only thing we could do to get into newly built housing, was to rent an apartment.
The amount of bad information and advise is pretty staggering – if you're adversely reacting to the environment you're in, the best thing you can do is remove yourself from it, then accept that you may never be able to return to it.
Anyway, this all sounds very familiar and you're welcome to reach out to me at <hn-name>@icloud.com – and that goes for anyone else dealing with similar stuff.
There’s many individual damage symptoms, but typically humidity somehow enters through the walls of the basement, making them damp/wet and thereby leading to mould infestation.
The expensive but thorough solution is to dig around the foundation and install a vertical damp-proof course around the outside walls. The walls would additionally require drying and depending on building material removing the old plaster and re-plastering.
If a concrete floor is damp, the culprit would be a crack which can be sealed with special injected sealants. If it’s an older type of floor, it may need to be replaced with concrete.
How did the basement infest the rest of the house, just regular air transfer or did humidity rise through the walls and caused infestation in the above-ground rooms?
No, that's not enough. Dormant/dead mold can still cause air quality problems. In most cases damaged material needs to be replaced. In some cases it's sufficient to isolate the damaged material to reduce its impact on air quality.
I'm from Finland and it seems that we treat mold much more seriously compared to other countries. I don't know if Finnish people have a genetic or environmental effect that makes people much more susceptible to get symptoms in moldy buildings, but it's super weird reading about how other countries treat mold...
As far as I know, air purifiers do not filter mold related particles in the air to any useful amount.
I think this is a big issue in US because the way they build houses, mainly with wood and gypsum. In case of water damage it is really hard to dry those materials.
When I learned about mold sensitivity I got concerned and started doing mold tests and looking out for mold exposure but eventually realized that nobody in my family is mold sensitive. The "not a big deal" attitude is right for most people, but we should be sensitive to those that are highly mold sensitive.
Mold is the kind of problem that is at most a nuisance for people who have the means to do something about it, but seemingly unsolvable for people who actually need a solution.
In many places this is not easy.
Unfortunately most of the population (including medical doctors) also has a similarly nonchalant conception of mold; that it's something that merely causes some allergies and sniffles for sensitive members of the population.
Toxic mold secretes _neurotoxins_ which will 100% destroy your life for years, if you get a bad enough exposure.
Read some of the experiences of mold survivors in this thread or elsewhere to get a sense of how bad this can be: it's horror-movie stuff.
Source: been through mold exposure myself. It wrecked my life for 5 years, and I still have lingering aftereffects.
> It is impossible to eliminate all mold and mold spores in the indoor environment. However, mold growth can be controlled indoors by controlling moisture indoors.
Dealing with mold is pretty easy, just get everything dry. No need to go crazy tearing the building apart to hunt for dormant/dead mold (obviously there is a correlation of moldy building with neglected buildings so you might have to demo/repair anyways). If air quality is a concern that can be addressed monitoring/filtering.
Afaik mold is only a big topic because of lawyers seeing a nice liability and the media a spooky story.