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Markus Keller
11-20-2009, 08:47 AM
Hi guys, did an inspection in a Condo yesterday. Building is new construction, modern, euro type designed by a famous architect. Client is looking to get out of the deal because she feels sick all the time living there. I started feeling congested after just being there an hour.
Approximately 1500 sqft. unit all ceilings exposed concrete, 50% of walls exposed concrete. Building corridors and lobby mostly exposed concrete.
Relative humidity in unit was 17-22%. Concrete surface readings were ok. Subsurface readings got higher and higher the deeper I probed. Didn't drill holes, rough concrete, just stuck probe in holes as possible.
I already told her my findings aren't likely to be good enough for a battle. For that she will need to hire a couple other guys I can refer who have much fancier equipment.
Anyone have any experience or data links with this much exposed concrete in a residential setting? Any help appreciated.
Almost forget, the unit did have that musty concrete smell. Occupancy of the building started spring of this year. Some finish work is still ongoing on the top floors.
Thinking of looking it up on Westlaw tonight to see if other buyers have had issues.
Thanks, Markus

Bruce Breedlove
11-20-2009, 10:49 AM
What am I missing? Is exposure to concrete now unhealthy?

Jim Luttrall
11-20-2009, 10:57 AM
No offense intended Markus, but you need to bail on this one or get the tin foil caps out and join the conspiracy theorist out there with all the other goofy ideas. If concrete is a problem, then almost every single house constructed in the last 40 years in Texas and every commercial building is a problem.

Bob Elliott
11-20-2009, 11:04 AM
New construction has a high humidity level the first year or two any way.

Markus Keller
11-20-2009, 11:47 AM
I don't think concrete in general is a problem. The place is weird though. I tend to like the sleek, minimalist euro trash stuff, not this one though. I think there really may be something wrong with this place. I'm on track with Bob's comment. I am trying to get info on roughly how long it takes for that much concrete to dry out. The building is about 40 stories.
As I said surface readings were in the green on my Delmhorst. Deeper readings got higher and on the few real deep readings the meter went crazy, red light, 99.9 reading
I will likely have to bail beyond the initial report.

Bob Elliott
11-20-2009, 12:11 PM
I just attended a great Water intrusion course last night for 3 CE credits (state approved) so it is to bad you were not aware of it.

Most drying occurs in winter though the last few winters have been warm so drying time has increased.

I would just make sure they are aware that the building will be settling and check window areas for any issues.

Condos are sort of my specialty (Condo Bob) so call me if you want any tips or have questions about Condos as they are different from inspecting a regular home.

I like to get on the roof and check parapet walls for no flashing under the coping as this is the cause of many issues in the brick built.

Concrete is designed to absorb and dissipate.

Jerry Peck
11-20-2009, 05:57 PM
Relative humidity in unit was 17-22%.

Markus,

That does not go with the rest of the concerns regarding moisture in concrete.

In fact, that is the opposite of elevated moisture in concrete, that relative humidity is way too low. The recommended relative humidity levels for comfort are 50%-65%, some saying even 45%-60%, and I know that even as low as 35% can cause skin to dry out, become irritated, flaky and itchy, etc.

And that is at 35%, you only had around half that, not good at all.

Typically, with that much concrete around the place, I would have anticipated a relative humidity closer to 65%-75% - going too high, not too low.

Matt Fellman
11-21-2009, 01:19 AM
The building is about 40 stories.


Not sure what you're trying to do scrutinizing a new construction high rise but unless you're the engineer, architect or other person working on the project you will most likely end up looking foolish.

I'm not trying to be harsh but this is the kind of stuff that gives us HIs a bad name... poking our noses where we have absolutely no business poking them. You have nothing to gain and everything to lose by brining stuff like this up.

Jerry Peck
11-21-2009, 07:05 AM
Hi guys, did an inspection in a Condo yesterday. Building is new construction, modern, euro type designed by a famous architect. Client is looking to get out of the deal because she feels sick all the time living there. I started feeling congested after just being there an hour.


Not sure what you're trying to do scrutinizing a new construction high rise but unless you're the engineer, architect or other person working on the project you will most likely end up looking foolish.

I'm not trying to be harsh but this is the kind of stuff that gives us HIs a bad name... poking our noses where we have absolutely no business poking them. You have nothing to gain and everything to lose by brining stuff like this up.

Matt,

Not necessarily.

Markus was hired to check out the "why", and Markus may be qualified to check out the "why".

Make blanket statements as you did without knowing the actually facts and ... "you will most likely end up looking foolish".

Your statement will be correct 'much of the time', but 'not all the time' ... something to consider before condemning someone as you did.

Marcel Cyr
11-21-2009, 09:09 AM
Here are a few points on concrete moisture:


Moisture meters should never be used to make the final determination as to whether or not concrete is dry.
No moisture meter of any type can give consistently accurate moisture readings across the different mixes and densities of concrete. Other components such as metal reinforcing steel, aggregate size and amount can cause false indications of moisture, especially with non-pin meters. Pin-type moisture meters are also not practical for moisture measurement due to the variable chemical and physical characteristics in concrete can cause false readings due to the electrical resistance that have nothing to do with moisture.


Keep in mind, that whether a floor or wall, relative humidity gradient throughout its thickness is greater at the 40% to 50% depth.


The RH will be much higher at those levels in depth. The surface of the concrete will more likely reflect the RH in the room or building which gives no indication of the potential for a dry concrete.

Here is an article that some might be interested in:

Concrete moisture vapor emission is a natural constituent of any concrete slab. It may be encountered as the emission of mix water during the drying process of a new concrete slab. Concrete drying creates an emission from the slab regardless of whether the concrete slab is below, on or above grade. Moisture vapor emission from suspended concrete is often overlooked as a potential cause of floor covering failure and this specific problem may be exacerbated by the use of light-weight aggregates . Beyond the drying process, moisture vapor emission may be the result of moisture vapor transmission from sources below the slab. The moisture source can be water trapped in a blotter course over a vapor retarder or moisture from the earth passing through the slab system. The major concerns surrounding this issue have been driven by changes in floor covering adhesives and coatings, which are more sensitive to moisture and alkali attack than previous materials. More important than floor covering system failure is the concept that Sick Building Syndrome and other I.A.Q. issues often start at the floor surface and are fed by the high sustained humidity levels created by excessive concrete moisture vapor emission.

The Calcium Chloride Vapor Emission Test has been developed to quantify, in a meaningful way, the amount of moisture vapor emitting from the surface of a concrete slab. It has been known as the R.M.A. Test, the Moisture Dome Test and by it's current name. ASTM has published a standard for the use of calcium chloride to measure moisture vapor emission from concrete, ASTM F1869-04 is the most current edition of the protocol. The results, reported as "pounds per one thousand square feet per twenty-four hours" are accepted by most flooring, adhesive and resinous coating manufacturers in establishing the benchmark of acceptability for the installation of their products over a concrete substrate. The test is performed by placing a quantity of calcium chloride in an open dish and placing the dish on a clean concrete surface. The dish is covered by a dome of approximately 9" x 9" and 2" in height. This dome is sealed to the concrete to prevent normal humidity in the room from affecting the test. The test apparatus is left undisturbed for a period of from 60 to 72 hours. At the end of the test period the dish is retrieved and any weight gain experienced by the dish is attributed to moisture leaving the concrete and being absorbed by the calcium chloride. Through calculation, the test results are extrapolated to approximate the equivalent number of " pounds" of emission as outlined above. It should be noted that the environment of the air space in the building envelope is of critical importance during the test series. As discussed earlier, the vapor pressure differential, created by temperature and humidity have a controlling influence on moisture vapor movement. Testing should take place in a building envelope conditioned to the same ambient temperature and relative humidity levels as the occupant/tenant will require during use of the space. If these conditions cannot be met, the ASTM standard offers tolerances which, at a minimum, should be honored if accurate test results are anticipated. Testing in a non-acclimated environment leads to erroneous results. Per ASTM, test density is required to equal 3 tests in the first 1,000 square feet, with one additional test per each additional 1,000 square feet of concrete slab surface.

And here is another article on concrete from a past business colleague:

http://rds.yahoo.com/_ylt=A0geu7z0DwhL448AaG5XNyoA;_ylu=X3oDMTEzNnN1ZjR nBHNlYwNzcgRwb3MDMQRjb2xvA2FjMgR2dGlkA0Y4MjNfMTA1/SIG=136b3n8qn/EXP=1258905972/**http%3a//www.moisturetesting.com/When%25203%2520lbs%2520is%2520not%25203%2520lbs.pd f (http://rds.yahoo.com/_ylt=A0geu7z0DwhL448AaG5XNyoA;_ylu=X3oDMTEzNnN1ZjR nBHNlYwNzcgRwb3MDMQRjb2xvA2FjMgR2dGlkA0Y4MjNfMTA1/SIG=136b3n8qn/EXP=1258905972/**http%3a//www.moisturetesting.com/When%25203%2520lbs%2520is%2520not%25203%2520lbs.pd f)


:)

Markus Keller
11-21-2009, 09:59 AM
Thanks for the info and article Marcel, great stuff. I will pass info along as part of the recommendations. Another HI gave me a referral for a guy who may do the type of testing you've mentioned. I have to give the guy a call.
Fantastic reply Jerry! It got me thinking in a reverse direction. I was thinking that this situation is about emission from the concrete. Jerry, your reply reminded me of comments concrete guys I grew up around used to make. Whether there is any scientific basis for it or not I have no idea. What they used to say was, "never sit directly on the concrete, it likes to suck the moisture right out of your bones".
Along that train of thought ... concrete surface and roughly 1/8" to 1/4" in readings were closer to normal 30-45%+. With the low ambient relative humidity, I'm now wondering if this may be a situation where all the exposed concrete is sucking the moisture out of the space. The excess dryness may be contributing to the clients health/congestion.
The client also stated that when its raining outside some of the wall and ceiling areas darken. Also small areas of the laminate floor blister or buckle up. Floors were fine when I was there. Concrete color didn't look abnormally dark. It hadn't been raining though either.
Matt, whether I am qualified or not could be easily debated but that isn't a real issue. I do not claim to have all the answers. The more messed up, bizarre or horrible building conditions are, the more likely it is that I will be the one getting the phone call. My business card states, "Troubled Buildings Specialist". I don't get this work because I have all the answers. I'm more like a rabid bloodhound in finding causes, answers and potential solutions. Overall I probably do more "adverse inspections" than regular HI. If all I did was HI, I'd be bored. I like the crazy stuff, trudging through V&O buildings, digging deeper and analyzing what's what.
Sometimes in these situations I am able to provide my clients with accurate causes and remedies. Other times the best I can do is give them a starting point, recommendations and referrals.
As I stated up front, I've already told the client my report is unlikely to be sufficient for a legal battle. However, my report will likely be a starting point to figuring out what the problems are and why the client 'feels' sick in her own home. Others will much better equipment and technical know how are likely needed in this situation. That however, does not preclude me from providing valuable, requested services to a client.

Jerry Peck
11-21-2009, 06:59 PM
It got me thinking in a reverse direction. I was thinking that this situation is about emission from the concrete. Jerry, your reply reminded me of comments concrete guys I grew up around used to make. Whether there is any scientific basis for it or not I have no idea. What they used to say was, "never sit directly on the concrete, it likes to suck the moisture right out of your bones".
Along that train of thought ... concrete surface and roughly 1/8" to 1/4" in readings were closer to normal 30-45%+. With the low ambient relative humidity, I'm now wondering if this may be a situation where all the exposed concrete is sucking the moisture out of the space. The excess dryness may be contributing to the clients health/congestion.
The client also stated that when its raining outside some of the wall and ceiling areas darken. Also small areas of the laminate floor blister or buckle up. Floors were fine when I was there. Concrete color didn't look abnormally dark. It hadn't been raining though either.


Marcus,

With the latest information you provided, I am thinking the weather is driving the moisture/water vapor (which increases or decreases the relative humidity) either: a) from outdoors to indoors - increasing the relative humidity; or, b) from indoors to outdoors - decreasing the relative humidity.

The weather, winds, relative pressure indoors/outdoors, rains, sun directly striking the building, and all kinds of other phenomenon act as an engine which drives water vapor through walls, even concrete.

Moisture travels from more moist to less moist, and when there is no rain and the sun is striking the concrete, the 'more moist' area would be indoors and the 'less moist' area would be outdoors, and with rain and wind, that would likely reverse.

Concrete walls are storage and dry-out systems, unlike frame walls with claddings which are drainage systems. That concrete wall *IS* going to get wet/wetter (moisture will increase) during rain and *WILL* become dry/drier during no rain and especially with sun striking the wall. That is confirmed by her saying that the concrete walls darken when it rains.

I'm guessing that if you went there after a good rains, a couple of days of good rain, especially with wind driven rain against those walls, that the relative humidity will rise indoors.

That is simply the design of concrete and masonry walls - they are storage and dry-out systems, that is what they do, and that is what those walls are doing.

Markus Keller
11-24-2009, 04:56 PM
For those of you interested, and apparently not many are. A ton of information can be found if you use keywords such as 'sick building syndrome' and 'building related illness'. Granted a fair amount of it is hyper sensitive, money making nonsense. Nonetheless once you sift through the junk there is some pretty interesting and valid reading. The EPA site has some really good info too.