High Rise Apartment Building

[Ron Bibler]

Any info would be great guys. Got a call from a Property management Company out of L.A. They have a Multi Unit Apartment Building in Down San Jose Ca. The area is about 40 Mils. Inland But they do get a cold off shore wind from the pacific ocean. Its been Raining on and off for the past month.

The problem. Moisture Intrusion. Interior ceilings and walls and flooring. adjacent to windows and balconies with sliding glass doors. The exterior of the building is old standard hard coat stucco. I do not have any information of the framing. ( Stucco over ply-wood ) ( over 2x6 wood studs ? )

My Job Starting with 12 units. Inspect the Interior walls and ceilings and floors of 12 units with water stains and know leaks. ( Windows and Balconies and adjacent exterior Stucco ) Find the areas that water/moisture is penetrating the building. According to the on-site Building Maintenance Manager the water is not coming in from the windows or the balconies. He thinks its from the stucco. I'm thinking the balconies. He says when it rains with a hard wind the water comes in though the cracks in the stucco.

These are random exterior/outer rooms on different floors.

I will be going in with Moisture meters and Infrared Cameras.

I'm not going in as a Home Inspector.

FYI....This is a WDO (Moisture Inspection) With Infrared and Moisture meters.

See the attachment for views of the building.

Your thoughts Guys...

Best

Ron

[Rick Hurst]

Ron,

What is the maximum coverage you have on your E&O insurance?;)

rick

[Ron Bibler]

Not a problem Rick... I do a lot of condos..100, 200, 300, unit complexes.

Best

Ron

[Chuck Lambert]

Ron,

I am envious!! I love jobs like that! Sounds like the windows, sliders and balconies may not be properly flashed.

Please keep us posted on your findings.

Chuck

[H.G. Watson, Sr.]

I'd start review at the top of the building first, roof accessible. Since all overhang protected could be from the top, the interior gutter drains camera'd & tested if nothing noticed from above.

[Markus Keller]

Based on water coming in at multiple locations and units, I would also start from the top down. Granted since everything was essentially built at the same time, all the caulk joints and flashings could be going at the same time but highly doubtful. Especially with the balconies being set into the building like that. I would concentrate on intrusion at roof flashings and possibly the stucco.
For the interior wall areas to be wet, that would be substantial water intrusion. Unlikely to come from a bad caulk joint around the balcony door, unless of course the joint is really wide open.
I would also suspect the balcony floors and drains. Are they cement, wood over rubber? Is there even a drain?
If the stucco cracks are sucking in water hopefully you'll see some darkening around the crack areas. Not like it really matters since you are an IR superstar. Good luck.
Did you word your proposal that invasive work may need to be done, that you would spec locations and their guys would make the holes, etc. Usually what I do, unless it is a good client with a track record then I'll consider making the holes.

[Ron Bibler]

Markus and H.G.... I have not been on site yet. The inspection is set for this Monday... I was thinking about the roofing. They want me to start with these 12 units... And see what information I can get... And then move on and cover the complete complex.
As the problems are not limited to these 12 units.

Yes If you look at the Balconies you will see drains from each deck/balcony.

Its going to be fun trying to find the points of moisture entry. It will either jump up and hit me in the face or I will be doing so long staring at areas.

There could be an extensive water damage and Fungus infection behind the stucco if these leaks have been going on for some time.

Best

Ron

[Ken Rowe]

I had a similar situation with these two buildings in Minneapolis. Ended up being lack of flashing at windows and patio doors.

They've spent over $4 million on repairs to date.

[Jerry Peck]

The most frequent cause in high-rise buildings is because the balconies were constructed with the top surface at the same level as the interior floor.

Adding to that is the lack of slope on most balconies.

And, when they do construct in a slope, the post tension tendons pull the edge of the balcony and curl it upward, as does floor warping from construction loads (dead loads of the building, not construction activities per se). Someone (I forgot who and which link it was) recently posted a link to very good information explaining that phenomenon.

First, though, is probably that the top of the balcony floor is at the same level as the top of the interior floor, so it does not matter if the balcony is sloped or not, there will be a problem. Adding to that is adding tile or ANYTHING to the balcony floor, which raises the balcony floor higher than the top of the interior floor slab (and water has a tendency to run downhill, which would be inside).

[Steven Turetsky]

I would plot out the entire complex. Floor by floor. unit by unit. Look for similarities... look for differences. Although it is possible, it is improbable that if there are 27 different leaks, it is due to 27 totally unrelated problems.

I would also like to be there when it is raining so I could see what the building is doing.

It may even be necessary to do mock testing.

[Daniel Leung]

......Its been Raining on and off for the past month.
The problem. Moisture Intrusion. Interior ceilings and walls and flooring. adjacent to windows and balconies with sliding glass doors......
.......According to the on-site Building Maintenance Manager the water is not coming in from the windows or the balconies. He thinks its from the stucco. I'm thinking the balconies. He says when it rains with a hard wind the water comes in though the cracks in the stucco......

Ron, please consider the negative air pressure caused by the exhaust fans in the building. It will suck the moisture in through the cracks on the exterior wall. We saw many new high-rise create positive pressure in the building to prevent leaking. They are using air blowers on roof and in basement to blow the air into hallways in the heating season (Vancouver has rainning season in winter). I would try to pressurize 1-2 leaking units to see the different.

[Ron Bibler]

Ron, please consider the negative air pressure caused by the exhaust fans in the building. It will suck the moisture in through the cracks on the exterior wall. We saw many new high-rise create positive pressure in the building to prevent leaking. They are using air blowers on roof and in basement to blow the air into hallways in the heating season (Vancouver has rainning season in winter). I would try to pressurize 1-2 leaking units to see the different.

Thanks Dan... That is an excellent point something to think about... Do you know of a little on site test for negative air pressure. ?

I found the Link. very good info on this issue. ( Controlling Stack Pressure In High-Rise Buildings by Compartmenting the Building (Canada Mortgage and Housing Corporation) (http://www.cmhc-schl.gc.ca/publications/en/rh-pr/tech/97103.htm) )

Best

Ron

[Steven Turetsky]

The "Stack" or "Chimney" effect" is caused more by natural convection and wind pressure. While the lower units are suffering from negetive pressure, the upper units will have positive pressure, and there is also a neutral point. Points can change with weather/season/barometric changes.

When holding unit doors or closed stairwell doors slightly ajar you can feel the pressure. Watch your fingers.

[Daniel Leung]

Do you know of a little on site test for negative air pressure. ?

I don't know, but I think you can use a digital barometer (http://www.coleparmer.com/catalog/productsearch.asp?search=digital+barometer) to measure the air pressure indoor and outdoor. Please read more from the following links:
Measuring Air Leaking in High-Rise 2008 (http://www.affordablecomfort.org/images/Events/32/Courses/1340/MULT8_Genge1.pdf)
University of Waterloo Test Hut (http://www.hpo.bc.ca/PDF/Research/TestHut/6.pdf) and BEG Projects (http://www.civil.uwaterloo.ca/beg/BEG_hut.htm)
Air Pressure Problems in High-Rises 2007 (http://www.informedesign.com/Rs_detail.aspx?rsId=2907)
Stack Effect in Light Well of High Rise Apartment Building 1997 (http://www.arch.eng.osaka-u.ac.jp/%7Ekotani/achrb97.pdf)
Characteristics of air pressure fluctuations in high-rise drainage stacks 2009 (http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6V23-4X0F3RC-1&_user=10&_rdoc=1&_fmt=&_orig=search&_sort=d&_docanchor=&view=c&_searchStrId=1151885048&_rerunOrigin=google&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=82e52daf3145de9e3490ccbcb1e42c7b)

[Jim Luttrall]

Do you know of a little on site test for negative air pressure. ?


Since you will be inside individual rooms which will likely be on different sides and floors of the building, you might just think about using smoke sticks or powder "puffers" around doors, outlets, etc. and just diagram whether the smoke goes in or out at each location. Make a diagram of the entire building exterior with positive and negative zones marked taking into account the prevailing wind and temperatures the day of you inspection. Then overlay the water damage areas to demonstrate a relationship (if any.)

[Jerry Peck]

I don't know, but I think you can use a digital barometer (http://www.coleparmer.com/catalog/productsearch.asp?search=digital+barometer) to measure the air pressure indoor and outdoor.


I use a digital manometer.

Dwyer Instruments - Manometers Table of Contents (http://www.dwyer-inst.com/Products/TOC.cfm?MainCategory_ID=294&iCurrentCategoryID=295)

[Joao Vieira]

sure, a digitam manometer is da bomb.

Sometimes the moisture intrusion issue can be in the assembly of the windows or doors too...For an older building that suddenly had problems a manufacturing defect does not seem likely.
When in doubt for this call for a leak test (negative pressure). It can be quite expensive. Normally these test should be done at the construction phase to save everyone's but. :D

[Jerry Peck]

When in doubt for this call for a leak test (negative pressure).


Are you referring to the water spray test with the water spray rack set up outside and the air chamber set up on the interior?

These case be set up for either positive or negative pressure, although the negative indoor pressure (which is used to replicate positive outdoor pressure) is MUCH easier to set up then to try to controllably set up a positive outdoor pressure - can be done but is much more difficult to set up and much more difficult to control, thus making it cost considerably more. Besides, the negative indoor pressure chamber is a recognized test method. :cool:

Don't just test windows and doors if there is a concern, also test the wall assembly, then test the wall assembly with the window assembly in it (to get the full effect - if needed).

[Joao Vieira]

Are you referring to the water spray test with the water spray rack set up outside and the air chamber set up on the interior?

Yes




a positive outdoor pressure - can be done but is much more difficult to set up and much more difficult to control, thus making it cost considerably more. Besides, the negative indoor pressure chamber is a recognized test method.

yes, but I never seen an outdoor one since normally requires more logistics when testing upper floors.

There is a third, the plain ol spray hose against whatever surface you are trying to test. Not sure about it's justification but can almost guess :D .

Anyhow,


Don't just test windows and doors if there is a concern, also test the wall assembly, then test the wall assembly with the window assembly in it (to get the full effect - if needed).
people often overlook this. If testing the window/door Ask the client upfront if the assembly to the wall is to be tested and get it in the contract. The window manufacturer does not want the liability of the assembly to the wall, unless the manufacturer employs the crew that installs windows/doors. The owner normally wants to test the window/door assembly and the assembly of the window/door to the wall.

Interior leaks can be caused from a variety of variables, incompatible finishes with sealants, manufacturing defects, field conditions, etc.

[Jerry Peck]

There is a third, the plain ol spray hose against whatever surface you are trying to test.

I know an inspector who made quite a bit of money doing that absolutely useless test, even though he was thoroughly convinced he was doing something beneficial, and likewise convinced his clients of same. No, he was not "doing it for the money", he actually thought it was of some use.


Not sure about it's justification but can almost guess :D .

Oh you know what the justification is for those people ... at least most of those people ... $$$$$ :D