6.13. SR 07-08-1996ITEM 6.13.
'ty of
iver
TO:
FROM:
MEMORANDUM
Mayor and City Council
Lori Johnson
Finance Director/Asst. City Administrator
DATE: July 8, 1996
SUBJECT: Library Roof
As the council is aware, the library roof is in need of repair. The city contracted with
Inspec to perform an inspection and prepare a proposal on the repair or replacement
options available. Attached for your review are a memo from Cliff Skogstad, Inspec's
report, and a letter from Murray McNair of the Library Board.
There are three items which the council needs to address on Monday night.
· The first is selecting a type of roof system. Information on this issue can be found
in the attached materials;
· The second issue is the funding of this project;
· The third is authorizing the advertisement for bids for replacement of the roof.
The estimated cost of this project is in excess of $50,000 according to Inspec's report.
Since this is an unanticipated expenditure, no funds were included in the 1996 budget
for this project. Some of the funding sources available include the library fund
balance, equipment reserve undesignated funds, an internal loan from the self insurance
or liquor fund to be repaid with future library tax levies, or a combination of these and
other sources. The council should discuss and at least identify preliminary funding
with the knowledge that the final funding will be based on the actual cost of the
project.
Action Requested
The council is asked to select a type of roof system, authorize the advertisement for
bids, and identify ~t funding source(s) for the replacement of the library roof.
13065 Orono Parkway · P.O. Box 490 · Elk River, MN 55330 · (612) 441-7420 · Fax: (612) 441-7425
'ity of
iver
FROM:
DATE:
SUBJECT:
MEMORANDUM
Mayor & City Council
Cliff Skogstad, Building Official
June 21, 1996
Elk River Library Re-Roofing Project
Provided for you with this memo is a copy of the letter submitted to me from
Inspec, Inc. There are two issues in this memo that will need to be
addressed by the council. The first is in regard to the opinions of the
probable construction cost (see Page 2 of this memo). As you can see these
prices have almost doubled from the original estimated cost Herzog Roofing
quoted the library one year ago. There are many reasons for this price
difference. For instance, from testing the material on the roof they have
determined that this material must come off completely all the way to the
roof boards and new insulation must be installed. Also, after talking to
Shane Burns from Inspec, he indicated that these numbers may be high but
he wanted to submit these numbers so when the bids come in it is easier to
justify a lower bid than a higher bid. In addition, because it is such a busy
construction year the bids will be coming in higher for this project.
The second item is in regard to the different types of roof systems proposed
(also on Page 2). One is the built-up roof system which we have at the Elk
River Fire Station and the second is the single ply roof system. This single
ply system is on the addition to the library. I met with the library board
regarding these two types of roofing systems on June 18, 1996. The library
board is recommending going with the single ply roof system. Mr. Murray
McNair feels that this would be the appropriate roofing system being it is
already on the addition. Also, he is concerned that the built-up roof system
would cause an odor problem caused from heating of the tars, etc. and feels
that the library would have to close down during construction.
In comparing these two systems the built-up roof system appears to have a
25 year life expectancy versus the single ply system having a 15 year life
expectancy. In comparison to the prices you will note that the built-up roof
system will cost $2,060 for a 25 year cycle and the single ply roof system at a
15 year cycle averages out to be $3,467. As you can see there is quite a
difference between the prices when you amortize out the life expectancy of
these roof systems. Please keep in mind that these life expectancies are
13065 Orono Parkway · P.O. Box 490 · Elk River, MN 55330 · (612) 441-7420 · Fax: (612) 441-7425
Page 2
based on experience from Inspec's jobs and the roof life performances. Either
one of these roof systems will work on the library since there is a parapet
wall which divides the addition from the older part of the library.
Both systems are an excellent roofing system and I would recommend either
one of the systems for this project. Therefore at this time I am requesting
that the Mayor and City Council recommend the system they prefer, either a
25 year built-up roof system or a 15 year single ply system. Once this
recommendation is made construction plans can be completed for this project
and the bidding process may continue.
If you have any questions before the meeting please don't hesitate to call.
s:\b&z\cliffX, cc6-21.doc
"l
5801 Duluth Street, Minneapolis, MN 55422 · Ph. 612-546-3434 Fax 612-546-8669
555 West Layton Ave., Suite 420, Milwaukee, WI 53207 · Ph. 414-744-6962 Fax 414-744-6981
~ngineering & ArcJ~'teCrural services ~or root~, pavements, exterior waJls, and outdoor sports Facilities.
,,4}NSPEC, INC.
PROJECT:
1996 Reroofing the Elk River Public Library
City of Elk River
REPORTED TO:
Mr. Clifford Skogstad
City of Elk River
P. O. Box 490
13065 Orono Parkway
Elk River, MN 55330
DATE: May 29, 1996
FILE: M960507-03
COPIES TO:
SCHEMATIC DESIGN SUMMARY
As discussed on May 22, 1996, we are sending you information regarding roof system options and our
opinion of probable construction cost for the above referenced project.
EXISTING CONSTRUCTION
On April 13 and 22, 1996, INSPEC, INC. conducted field verification of the existing roof system for
the Elk River Public Library. During the field verification, test openings were made through the
existing roof system to the existing structural deck. Test openings were also made at roof edges,
expansion joint curbs, and an obsolete skylight curb. The existing roof system is a IRMA roof system
consisting of 1-1/2" diameter aggregate ballast over a filter fabric laid loose over a 1" extruded
polystyrene insulation laid loose over a 45-mil loose laid EPDM membrane over 1.7" extruded
polystyrene insulation mopped to a two-ply organic asphalt underlayment mopped to a one-ply red
rosin underlayment tack-nailed to the existing wood deck.
At some of the test cuts taken, water was found in the system between the membrane and the
underlayment. Because of the wet conditions of the existing roof system materials, it is not
recommended that any of these materials be salvaged and used in the new system.
The original construction documents show a conventional gravel surfaced built-up roof. The current
IRMA roof system in place was installed approximately 8 years ago according to local personnel.
Documentation of this system was not available for our use at this time.
PROPOSED SYSTEMS
It is our opinion, based on field verification of the existing conditions on this area along with an
understanding of your needs and expectations, the viable roof system options include the following:
As a mutual protection to clients, the public and ourselves, all reports are submitted as the confidential property of clients and our written
authorization is necessary to publish any statements, conclusions or extracts from or regarding our reports.
.j
,,4[NSPEC, INC.
File No. 960507-03
May 29, 1996
Page Two
Built-up Roof System - Four plies of fiberglass felts in asphalt moppings with an asphalt flood coat
and aggregate surfacing.
This system is resistant to puncture and abrasion and is a time-proven system. A drawback with this
type of system is the asphaltic smell at the time of construction. With quality design and installation,
this system should last approximately 25 years and will require minimum maintenance during the life
of the roof.
Adhered EPDM Single-ply Roof System (One ply of.060" EPDM membrane fully adhered to the
new insulation with no surfacing)
This system is less puncture resistant than the BUR roof system, it would not have the asphaltic smell
at the time of installation, and would match the system installed on the new adjacent addition. With
quality design and installation, and periodic walkovers, this system should perform satisfactorily for
approximately 15 years with only minor maintenance required.
An IRMA roof system (similar to the existing) could not be recommended with this system. If any
leaks occur, it can be difficult in locating the water entry point due to the insulation and aggregate
ballast over the membrane. This system also has a tendency to trap water between the top insulation
and the membrane which could lead to premature failure of the glued seams (which has happened to
the current system in place). Also, at the present time, there appears to be a slight deflection of the
existing deck caused by the additional weight of the ballast. If a new IRMA system was installed, a
complete structural analysis would need to be done.
OPINION OF PROBABLE CONSTRUCTION COSTS
The following cost estimates are based on a total of 67 roofing squares:
Built-up Roof System 67 squares ~ $800/square =
Adhered EPDM Single-ply System 67 squares ~ $780/square =
$54,000.00
$52,000.00
LIFE CYCLE COSTS OF THE PROPOSED SYSTEMS
Built-up Roof System
Single-ply Roof System
$54,000 + 25 years = $2,060/year
$52,000 + 15 years = $3,467/year
As a mutual protection to clients, the public and ourselves, all reports are submitted as the confidential property of clients and our written
authorization is necessary to publish any statements, conclusions or extracts from or regarding our reports.
.i
,, I'NSPEC, INC.
File No. 960507-03
May 29, 1996
Page Three
REMARKS
We recommend reroofing with the built-up roof system from a life cycle cost standpoint plus it has
better resistance to physical abuse.
We are anxious to continue our design work and will do so once a roof system has been selected. If
you have any questions or comments regarding this report, please feel free to call.
INSPEC. INC.
By
Shane Bums
SB/cs
Gary,. Patrick
As a mutual protection to clients, the public and ourselves, all reports are submitted as the confidential property of clients and our written
authorization is necessary to publish any statements, conclusions or extracts from or regarding our reports.
,June 28,1e0~
City of ~l.k River
~ar Yr.Yavor and Elk~ver cJtv council me~bers,
Cliff Skogstad presented Inspec's report and mecommendations
to the Library Board, as he will likely discuss before tRe Council.
As you will see, Inspec comes do~..~n in favor of the bui!t-uv
roof system because, even tbou?h it would be more exvens~ve to
instal, over time, the cost par year would he lower. ~tv experience
with built-up f]at roofs tells me t.hat no p~thh and Era. vel roof
wJ. ll last 25 years.
I researched the lil~rary recor:ls and found a chan?e order dated
Sept.7,197Z:, si~ned be Yerri]] .A. Birch BIA of YcEnary ~nd Yrm£t
detai].Jn~ an IP,~'A system usin~ three ]avers(a Z:3f! and two-2~f felts
mopped on with steer asphalt) The next letter was Pct. g,lOgl.
(Edwards Sales,copy Attached) Tb~.s details the rep]acment that was
needed six years after comvletion.
The IJbrary Boardhas asked that I relay our feelin?s to the
city.
1. The adhered EPDY system would match the membrane on the new
addition, which is less tho. n two years old, and would not reouire
rock ballast.
2. The stench from that "tar cooper" could be a problem for
the library as well as for the nef?bbors.
3. ~:Tho will?ive you a 25 year ~uarantee on the b6ilt-up system?
Thank you for your consideration of tb~s problem.
Sinmerely,
Murray Wc Nair
CAMBRIDGE STREET. MINNEAPOus. MINNESOTA 55421] · PHONE 612/929-6794
ctober 6, 1981
CITY OF ELK RIVER
Elk River, Minnesota 55330
Attn: Mr. Rick Breezee, Building Inspector
Dear Mr. Breezee,
We have solicited bids today for the installation of a new
roof membrane on the Elk River City Library. This action
was requested by Dow Chemical in accordance with the pro-
vision of the IRMA 'warranty agreement on the building.
The roof contractors will be contacting you or Ms. Bender
to inspect ~he roof prior tq bidding. We wou~ appreciate
your assistance in accomodating them.
When the work is completed we will deliver to you a new
warranty of at least 5 years duration from the manufacturer
of the membrane system that was installed. In exchange we
ask for release from further responsibility under the ori-
ginal IRMA warranty.
We cannot promise that the repair will be completed yet
this fall. If it isn't, we naturally will continue to
service the IRMA warranty.
Very truly yours,
EDWARDS SALES
I~oger~~yber~
RN/jj
cc: Ms. Mary Bender, Librarian
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