Volume 40,   Issue 11                      November  2005

Dear USG

The Case for 
On-Site Hose Tests

Dear USG,

In the past 50 years, I have been involved with a number of projects where the simple AAMA hose test (AAMA 501.2) would have demonstrated the potential for uncontrolled water leakage. In some of the below-named projects, the walls or windows were completely replaced because they could not be rehabilitated. The projects with an asterisk involved brick masonry that was not properly flashed or sealed. The windows were blamed for the water leakage that occurred in the masonry.

5th Avenue Apartments (New York City) (Stone flashing joints not sealed);
Lincoln First (Rochester, N.Y.) (A disaster with ends of gutters not sealed);
IBM (Almaden, Calif.) (Sill penetrations not sealed);
St. Bridget Church* (River Falls, Wis.);
County Hospital* (Nazareth, Pa.);
Bell Telephone* (Little Rock);
Citibank* (Houston);
Apartment House* (Richmond, Va.);
Fidelity Bank* (Richmond, Va.);
Sunset Ridge Condo* (Asheville, N.C.) (Brick mold not sealed);
Woodbridge Hilton (Woodbridge, N.J.) (Sloped subsill with inside edge lower than outside);
Bank Central America (Managua, Nicaragua);
Tishman Apartments (Fort Lee, N.J.) (Preset metal flashing was cut away and not restored);
Law School CUNY (Queens, N.Y.);
Hyatt Regency Hotel (Santiago, Chile);
Voyager Condo (Pompano Beach, Fla.);
Piper Dunes Condo (Amelia Island, Fla.);
Caribbean Tower Apartments (Miami Beach, Fla.) (Missing gutter splices);
Stockley Park (London, England) (Faulty pressure equalized design);
Harbour House North (Miami Beach, Fla.); and
FIU Business School (Miami, Fla.).

In lieu of the AAMA 501.2 hose test, there are cases when a fire hose water spray test is more meaningful. Examples where such tests were conducted by me are:

Bank Central America (Managua, Nicaragua);
Family Finance (Miami, Fla.);
Baptist Medical Center (Winston-Salem, N.C.);
First Union Bank (Raleigh, N.C.);
3200 Wildwood Skylight (Atlanta);
New Orleans Aquarium (New Orleans);
National Gallery of Art Skylight (Washington, D.C.); and
Stockley Park (London).

In order to cover a large area of curtainwall or skylight with a deluge application of water, it is suggested that the joints in the system be subjected to a fire hose test in lieu of any other tests considered. The fire hose test is best suited where access from the ground is convenient.

The reasons for this recommendation are:

1. A much larger area can be covered in a given length of time;
2. Properly installed, a fully sealed system should be able to resist this kind of test considering that there are no operable windows;
3. Most leaky walls and skylights leak with only an application of water and no wind pressure is needed; 
4. This test provides for more severe wetting than the AAMA 501.2 hose test and is only suitable for a fully sealed wall; and
5. This test covers flashings, penetrations and transitions, which could not be tested by other means easily.

It is extremely important that any field tests be conducted when only a few units have been installed so that any problems can be resolved early in the installation sequence.

A.A. Sakhnovsky
Construction Research Laboratory

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