A dirt smell when the windows are opened?

I got a client that has a dirt smell in their basement when the windows are open. The house is 12 years old and the basement was finished two years ago. About a year ago they started experiencing burning of their throats and lungs when they are sitting in the basement. Both occupants are probably in their late sixties. I had a highly certified fabric cleaner clean the carpet and the upholstery, but still have that smell. I cannot find any moisture anywhere. Looks like the construction of the home is very good. Has anybody ever heard of a smell getting worse when the windows are opened? I have no idea where to go from here.

sounds like it is pulling in from somewhere for sure , what type of wall finish is it.


I could think it could be moisture under the slab and there is a crack in the concrete somewhere, but it would not cause the irritation to their throat and lungs.

The Five Home Construction Materials that Pose the Highest Health Risk to You
by www.SixWise.com

Building a new home certainly has its up-sides: no avocado green appliances, paisley wallpaper or, worse, hidden mold growing in the basement. But new homes are not without fault. Home-building materials are often toxic and getting them brand-new makes no difference.
Although you may not smell, see or taste it, construction materials emit various gasses and other compounds into your home, many of which are highly toxic. This is part of the reason why the Environmental Protection Agency says that indoor air can be two to five times (and even up to 100 times) more polluted than outdoor air.

Decks and playgrounds made of pressure-treated wood can contain arsenic, pesticides and other toxins that can be easily transferred onto your child’s hands … and into their mouth.

This doesn’t mean you should never consider building a new home. While homes that have been lived in a few years may actually be a little healthier since the materials have had a chance to do some of their initial out-gassing, very old homes can bring up a whole new set of problems (lead paint, asbestos, mold, etc.).
Upon building a home (and making the seemingly endless decisions that go along with it), put some consideration into the actual materials that will be used. Often, safer, healthier and more environmentally friendly options exist, and not necessarily for a greater price. Following are some of the especially toxic building materials to watch out for, along with some alternatives to build a greener, healthier home.
1. Carpeting
Carpeting, though a soft and welcoming addition to most rooms, can be so hazardous that we’ve previously devoted an entire article to its dangers. The problem is that almost all carpeting in the United States (of the wall-to-wall variety) is made of synthetic materials, which outgas toxins into your home. Just a sampling of the hazardous materials in carpeting include:

  • Petroleum byproducts and synthetics (polypropylene, nylon, acrylic)
  • Soil and stain repellents
  • Vinyl or latex
  • PVC
  • Urethane
  • Antistatic sprays
  • Artificial dyes
  • Antimicrobial treatments

Some of these “ingredients” have been linked to cancer, while others may cause hallucinations, nerve damage, respiratory problems, thyroid damage and damage to the immune system and brain development.
2. Engineered Wood Products
Engineered wood is made by gluing together layers of fragmented wood. It may be used for cabinets, furniture, wall paneling, kitchen counters and more, but the adhesives and bonding agents it contains emit pollutants, including formaldehyde, into the air.
Using natural, solid wood for furniture, cabinets and other indoor wood products can eliminate this problem. There are also engineered wood products out there that contain no, or reduced levels of, chemicals.
3. Oil-Based Paint, Wood Finishes and Paint Strippers
Oil-based paints and stains contain potentially 300 toxic chemicals and 150 carcinogens, according to a John Hopkins University study. Among them are alkyl resin, kerosene, lead, lithopone, mercury, methylene chloride, methyl ethyl ketone, mineral spirits, toluene, trichoroethane and xylene.

Engineered wood cabinets, countertops and furniture can emit formaldehyde into the air, while oil-based paints contain a myriad of toxic chemicals.

Paint strippers, which are required to remove oil-based paint (and to clean brushes, etc.), also contain toxic and highly volatile chemicals such as methylene chloride, toluene, acetone and methanol.
Vapors from oil-based paints and strippers accumulate in the air while painting, and can irritate the eyes, skin and lungs.
A much safer alternative is to look for latex water-based paints or low-volatility paints, which have fewer toxic solvents. Water-based paint strippers are also available, and though they can still cause eye and skin irritation, they are less toxic than oil-based strippers.
4. Pressure-Treated Wood and Wood Preservatives
Wood preservatives are used to protect wood from fungi, bacteria and parasites. It can either be applied to the wood’s surface or injected into the wood, in which case it’s called pressure-treated wood. Wood preservatives include toxic pesticides, creosote, arsenic and more.
Most treated wood used for residential homes (decks, playgrounds, etc.) contain a mixture of copper, chromium, and arsenic called chromated copper arsenate, or CCA. Studies have found that the chemicals leach into the ground and transfer to the skin from everyday contact.
This is particularly dangerous for children, who may play on a treated-wood playground or deck, then put their hands (which may be contaminated with arsenic or other chemicals) in their mouth. Sawdust and smoke from burning treated wood is also toxic if inhaled.
There are many alternatives to highly toxic pressure-treated wood. Sometimes, wood preservatives are not necessary, as wood can keep quite well if well-ventilated and kept away from soil (in some cases a water repellant or sealer may be needed). You can also choose hardier woods that are naturally weather-resistant, which include cedar, redwood and cypress.
Finally, if you must use treated wood, certain varieties contain less toxic chemicals than others (for instance, you can buy pressure-treated wood that’s arsenic-free).
5. Insulation
Most people are aware of the dangers of asbestos in insulation, but even standard fiberglass insulation can be dangerous. Bits of fiberglass can be toxic if inhaled (some have compared their dangers to those of asbestos), and many varieties also contain formaldehyde that can be released into the air.
You can purchase safer types of insulation from green building suppliers, such as cotton insulation or insulation made from recycled paper that is formaldehyde-free and can be installed without having to use a respirator.
Green Building Resources
There are many builders and construction supply companies out there that only carry non-toxic, sustainable building materials. Here are a few to check out:

There would happen to have a floor drain by chance? if so the trap could be dry or worst not connected .

Hell yea! It’s called stack effect…

Would the stack effect cause burning of the throat?

I am leaning towards Formaldehyde.

Does anybody else have any other ideas?

The floor drain has the dehumidifier draining in to it. So the trap is getting plenty of water.

I can’t tell you what they are reacting to, but I can tell you that if you open the windows you provide the pressure differential for air to move through the openings into the house.

You may not get to where or what the smell is, but you can stop it from getting into the house. Weatherization inspection for thermal bypass and proper ventilation will get you started.

But are you sure it is actually going somewhere and not draining under the slab?

I have that every Morning after coffee :wink:

But that would be fresh air entering through that window…

Not if it is the first floor windows ( talking about the basement)

[quote=“jbraun, post:8, topic:69796”]

Would the stack effect cause burning of the throat?


NO but a bad case of heartburn would. huh huh huh :mrgreen:


The symptoms and smell has me leaning towards mold which is being disturbed by the stack effect caused by opening the windows. I would suggest invasive testing or borescope behind the basement walls. Don’t forget to look in the basement ceiling area.

Windows let more air out than in.

Listen to what your client is telling you. That is a start.

#1 you have a smell. Is it outside or in? If it gets worse when you have the windows closed it would be inside. As it gets worse when windows are opened, it’s outside the inner surface of the building envelope.

#2 how does it get in? There must be a hole. There must be a pressure differential across that hole for the air to move one way or the other.

#3 What tests do you need?
A micro manometer will tell you about building pressures in the house and in each room. Also at every elevation. Must find the neutral plain.

Thermal imaging will tell you where air paths are occurring inside the building envelope.

Blower door will control the air movement so an assortment of tests can be conducted to see where the air (thus the smell) is moving from.

Mold testing from where the air is coming from may identify or eliminate the potential source of smell.

You move on from there.

I do these all the time (have one this afternoon). It is not a job for the weak at heart. You need connections with other types of good contractors and engineers. It may take dismantling the house to some extent and the client must be ready to do that before you start.

This is not a job your are going to get done in one trip or 2 hr inspection for $195.99. I charge $500 to show up and “take a look” (but you must know what to look for). This is not a “Home Inspection”.

Excellent post and damn good advice. In the words of Dirty Harry, “A man has got to know his limitations.” Any time an inspector gets over into areas where they are NOT performing a standard home inspection, they need to stop, step back for a half a second and asked themselves, “Am I in over my head, do I know what in the hell I am doing here and do I now need to defer this job to a TRAINED profession in that discipline?” Be helpful but it is not a crime to say, “I DO NOT KNOW”. I just threw a job yesterday to another inspector here because the customer thought he needed a home inspection, but after talking for a few mins, I stopped him and told him he needed someone trained and experienced in IAQ, mold, thermal imagining and whole host of other ancillary services. Gave him the name and number of another iNachi member who specializes in all those and I slept like a baby last night.

I thought James was referring to opening the basement windows.

What David said makes sense.

I figure so Marcel…