HomeMy WebLinkAboutItem 06.n
Date: Item No.
CHANGE ORDER WITH McDOWALL COMPANY
FOR CITY HALL ROOFTOP UNIT REPLACEMENT
Proposed Action
Staff recommends adoption of the following motion: Move to approve change order with
McDowall Company for city hall rooftop unit replacement
Overview
On August 3, 2020 the City Council approved a contract with McDowall Company for the
replacement of a roof top unit at City Hall. The contractor started to remove the old roof top
unit and it was found the area under the roof top unit was not constructed per the original
construction plans. The roof top unit was not set in place over the proper structural supports
and numerous items were found not to be up to code under the unit. There was no way to
determine the existing conditions under the roof top unit until it was removed. Staff looked at
many alternatives to address these issues. It was ultimately decided the best and most cost-
effective approach was to make the necessary structural changes and bring the items under the
unit up to code under the current contract. Since this is a change in condition to the contract a
change order is necessary to amend the contract. The 2020 facility capital outlay will reflect this
change.
Primary Issues to Consider
• Why were the change order items not in the original rooftop unit contract? The City Hall
construction drawings for the roof top unit area were not the same as what was constructed.
There was no way for staff or the contractor to determine the existing condition under the
roof top unit until it was removed.
Supporting Information
• Change order Explanation
Financial Impact: $ Budgeted: Y☐ N☒ Source:
Related Documents: (CIP, ERP, etc.):
Envision Lakeville Community Values: Good Value for Public Services
Report Completed by: Paul Oehme, Public Works Director
23,990.00
December 7, 2020
Budget Code 4010.6540
Facilities Capital Outlay
5600 International Pkwy, New Hope, MN 55428. Service 24/7 320-203-9336. Lisa 612-930-6807
October 16, 2020
City of Lakeville
Attn: Tommy Robinson
Re: City Hall Change Order Explanation
McDowall Comfort Management started to remove the existing rooftop unit. After removing the unit, we
found the existing curb was not insulated and there was loose insulation sitting in the ceiling space below
the unit in what we assume was an attempt to stop the cold air from penetrating the space. There is a
sprinkler head right under this unit, so you are lucky that never froze. This curb was just wrapped in
plywood which is not up to code. It was determined a new curb would need to be installed to properly
meet current code requirements. We did bring you and your City Inspector up to the roof to see what we
found at that time.
In addition, we found the existing unit was not set in place over the proper structure per the original
structural roof plan drawings. We brought out a Structural Engineer to evaluate what would need to be
done and it was determined we will need to move the unit back about four feet to sit above the two sets of
double bar joists and install two (2) 20’ C Channel sections to support the framing at the roof opening.
Also, we will need to drill a 36” x 24” hole in the 8” concrete block wall to install a lintel to support the
rooftop unit above the men’s restroom.
The existing exhaust fan and water line vent will also need to be relocated 10’ away from unit per code for
the new unit so it does not exhaust back into the building. The existing exhaust fan is sitting on plywood
so a proper curb will be installed for this when relocated.
The decision was made to put the old rooftop back on until we could evaluate what would need to take
place to properly install the new rooftop unit per current code. Until the existing rooftop unit was
removed, we would have had no idea of the existing conditions below it.
Items that will need to be done to complete this project:
Day One: Electrician and service technician disconnect old unit, remove, and crane unit down. Crane up
the new curb for the rooftop and exhaust fan. We will water-tight the opening at the end of the day.
Concrete cutter to cut through the wall. Plumber to relocate the 2” water vent line.
Day Two: Work with McDowall Roofers to install new curbs and roof them in and the relocated vent
line. Install the additional structural and weld into place. Install ductwork below for the new location of
unit.
Day Three: Crane up new unit. Install new unit. Electrician to run new wiring for the unit. Finish
ductwork below. Controls Technician to connect controls for new unit. Start-up rooftop unit. Clean up
of jobsite.
5600 International Pkwy, New Hope, MN 55428. Service 24/7 320-203-9336. Lisa 612-930-6807
Included in this proposal are:
•Structural Engineer Certified Report $2,100.00
•Two crane lifts $3,000.00
•New curb (were just going to add an adapter originally credit back of ($800.00) $980.00
•Electrical Work $1,575.00
•Concrete cutting of wall $2,600.00
•Plumber to relocate water vent $1,700.00
•Roofing - $9,415.00
•Structural supports/welding $820.00
•Additional ductwork $1,800.00
We PROPOSE hereby to furnish labor and materials - complete in accordance with the above
specifications: $23,990.00.
Clarifications and Exclusions:
Work to be performed during normal business hours.
Any additional work beyond the above scope is not included.
If any further work needs to be performed, we will provide you a separate proposal and wait for your
approval.
Sincerely,
Lisa Linell
McDowall Comfort Management
612-930-6807
lisal@mcdowallco.com