6.4. ST 02-05-1996ITEM 6.4.
'ty of
E
MEMORANDUM
River
FROM:
Mayor and City Council
Cliff Skogstad, Building Official
DATE:
January 31, 1996
SUBJECT:
Repair of the Water Damage and
Correction of the Sprinkler System
at City Hall and the Library
As you are aware of the problems we have been having at City Hall regarding
the freezing of the sprinkler line and the water damage that occurred as a
result of the broken line, also the heating system at the library, I am hopeful
this memo will bring you up to date regarding the corrections of both
buildings.
The first building I wish to address is the library. On or about December 11,
1995, a heating coil in the air handling unit froze. This was due to the
improper calculation of make-up air coming into the air handling system.
After working with Rick Westling, the architect for the project, we
determined that there were miscalculations given for the amount of air
coming into this system, thus, freezing the coil in the unit. Rick Westling
contacted the contractors, replaced the coil, and put it back on-line. I met
with Greg from GR Mechanical at the library regarding the corrections. I
also met with Pneumatic Controls who were out there repairing one of their
wires for a control box.
After looking at the corrections of the system, Centrasota Mechanical will
have to come out to reposition this coil. It is allowing too much air to go by
the coil and not through the coil which is not making this system energy
efficient.
My biggest concern regarding the system is that the water boiler system do
have chemicals for rust and scale inhibitors but have nothing for freezing
problems. In my conversation with Greg from GR Mechanical, we talked
about turning this system into a glycol system. This product is an anti
freezing product. The same chemical is used in our boiler system at City
Hall. Even though the mechanics are working at this time, I feel that it
would be good insurance changing this system over to a glycol system, just in
case the mechanical system fails to operate as it has done in the past. Greg
13065 Orono Parkway · P.O. Box 490 · Elk River, MN 55330 · (612) 441-7420 · Fax: (612) 441-7425
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has not given me a price at this time for converting this system over, but he
felt that it would be less than $500.
The second item is the repair and corrections at City Hall. On December
12,1995, a 2 inch by 1-1/4 inch tee froze and broke in the soffit area at the
main vestibule. This freezing allowed the sprinkler system to run for
approximately 8-10 minutes allowing approximately 1500-2000 gallons of
water into the building. Since that time, Granell Sprinkler Systems came
out and repaired the damage to the sprinkler system.
After further investigation of what caused this freeze, we have determined
that the insulation assembly has failed the same way it did two years ago
when we had two sprinkler heads go off, one at the vestibule and one in the
audio visual room. It appears that the tape they use to secure this insulation
to other insulation does work, however, the problem occurs when they use
this tape to secure it to either steel studdings or steel I-beams. What is
occurring is the steel itself is in either an expansion mode or a contraction
mode which is loosening the tape to this beam and allowing this insulation to
drop down. Once the insulation does drop down, we have an abundance of
cold air coming into the areas.
This building was designed with the insulation envelope above all the
sprinkler systems and soffited area and, in theory, would work if we did not
have the failure of the insulation since we do have heat penetrating the 5/8
inch sheetrock and warming these areas of unheated conditions.
With the running history of failures of this insulation, my current concerns
are with the sprinkler system prior to the correction of the water damage.
The five areas of concern are the soffit area in the main corridor from the
vestibule going west to the end of the windows, the vaulted area in the
council chambers, the audio visual room, and the upper mezzanine area for
the record keeping and mechanical room. These areas are of concern because
of the insulation located in these areas and the uncertainties of a future
failure in these areas, as these areas are very difficult to access to determine
a failure.
Once again, insurance is required for these areas to assist us in possible
future freezing problems. Numerous ideas were worked on for these
corrections. One was to create a dry system for all of City Hall. After
reviewal of the plan it was determined that we have a loop system and the
cost to turn this into a dry system would be a very substantial amount. The
best idea that Granell Fire Protection and I came up with was an antifreeze
loop system. This system would take care of the records and mechanical
room, the council chambers, and the audio visual room. The price would be
$3,100 for the council, records, and mechanical room; $1,250 for the audio
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visual room. What they would do is create a loop in the 4 inch supply feeding
these areas and install a backflow preventer. This would allow the antifreeze
to remain in these general areas and prevent the possibility of freezing. The
one area they could not do this type of system in is the soffited area in the
corridor.
The one nice thing that has taken place in the time frame of trying to correct
these areas is time itself. Since we have allowed the openings to remain in
the corridor area, allowing heat to go up into the soffit, it has kept the branch
lines of the sprinkler system from freezing. Since this is a working solution, I
have contacted Jim from B & D Plumbing and Heating. At this time, he is
writing a proposal for installing return vents in the soffit area allowing the
heat to penetrate more efficiently into the soffit area and hopefully
eliminating the possibility of freezing. Once they cut the soffit open we can
repair the insulation that has fallen. This insulation was the problem of the
frozen line to begin with.
After talking with Jim from B & D regarding the solutions of this area, it has
been determined that the cost will be less than $500 for the installation of
these vents. The biggest cost is due to this area being a rated corridor. As
such, fire dampers will have to be installed into these openings. These
dampers will close if a fire does occur and will maintain the 1 hour rating.
These above corrections must be completed prior to the corrections of the
water damage.
After reviewing the plans and the insulation envelope system for this
building, I feel that with these corrections we have taken care of all the
problem areas and I am hopeful that this problem will not happen again.
There are, however, always concerns regarding a sprinkler system in the
Minnesota cold weather. We have had numerous calls at the Fire
Department regarding sprinkler heads going off in the vestibule areas.
These areas are always a concern because of ice build-up on the threshold
and allowing the door to remain open and having cold air coming on to these
sprinkler heads. I am hopeful with proper maintenance of our doors and
keeping these vestibule areas warmer than the rest of the building, we
should not have a concern.
I wish I could give these corrections a 100% possibility of no further failures,
but, there is always unforeseen problems. I would, however, give these
corrections a 98% probability of no future problems.
The last item is the correction of the water damage. Out of three companies I
have only received one bid price for the water damage corrections. This bid
for the repair of the sheetrock and painting is approximately $1,780, and this
item should be taken care of by the insurance company. The other part of the
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corrections are the three doors that have cracked. At this time I am waiting
for a price from Art Hidde Construction for the repair or replacement of these
doors. Again, this should be covered by insurance.
Since the time of the water damage, as the building and sheetrock continues
to dry, we have found additional problems which will have to be addressed
during the corrections. Even with these bid prices I am anticipating an
additional amount. This amount is still undetermined until we get the
company to come in for the final repairs. This has always been a problem
with water damage. As the building continues to dry out, there is always a
tendency of wood and sheetrock continually shrinking.
I am hopeful that this memo has cleared up any concerns regarding what has
transpired since December, 1995. I am hopeful that your approval will be
given regarding the corrections and repairs which are underway at this time.
If you have any questions regarding these corrections, I can be at the
February 5th meeting to answer all of your concerns.
Recommendation
Council is requested to:
Make a motion to approve spending a maximum of $500 from the Self
Insurance Fund to install a glycol system for the boilers at the Elk
River Library.
Make a motion to approve spending a bid price of $4,350 from the Self
Assurance Fund for the work required to maintain our sprinkler
system from freezing.
Make a motion to approve spending a maximum of $500 from the Self
Insurance Fund for the installation of registers in the soffit area of the
main corridor to eliminate possible future freezing of the sprinkler
system.
These motions are as outlined in the memo.
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