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HomeMy WebLinkAbout6.m. Receive Bids and Award Contract - Rosemount Community Center Water Intrusion RepairsAGENDA ITEM: Receive Bids and Award Contract Rosemount Community Center Water Intrusion Repairs AGENDA SECTION: Consent Bid Amount PREPARED BY: Dan Schultz, Parks and Recreation Director AGENDA NO $93,600 ATTACHMENTS: None APPROVED BY: Dili RECOMMENDED ACTION: Motion to receive bids and award the contract to Minnesota Construction, the lowest bidder, who bid the project for $93,600. Y Contractor Bid Security (yes /no) Bid Amount Minnesota Construction, Rosemount Y $93,600 Omni Construction Services, Prior Lake Y $98,000 Derau Construction, Burnsville Y $105,800 Meisin:er Construction, South St. Paul Y $116,300 4 ROSEMOUNT CITY COUNCIL City Council Regular Meeting: July 5, 2011 EXECUTIVE SUMMARY ISSUE The 2011 Capital Improvement Budget (CIP) includes $100,000 to make repairs to the Rosemount Community Center to stop water from entering the building due to the faulty installation of some of the flashing on the south side of the building. The funding comes from SKB revenues collected in 2010. BACKGROUND In the spring of 2010 staff received a report detailing the water intrusion problems at the Rosemount Community Center. There is water coming into the building in a couple of locations on the southern end of the facility near the Ice Arena. This is the same problem that the National Guard has dealt with in the past on their part of the building. The City Council approved hiring CNH Architects to create the plans and specifications for the project due to the positive working relationship with the City as a result of their work on the Steeple Center. They were also the architects used by the National Guard to provide architectural services during the repair of their water intrusion issues. SUMMARY The City received four bids for the project and they are listed in the bid tabulation table below. Bid Tabulation Staff is recommending the City Council receive the bids and award the contract to Minnesota Construction, the lowest bidder, who bid the project for $93,600. Rosemount Community Center Water Intrusion Project Information Existing Conditions There are two areas that water has been intruding into the interior of the Community Center. First there is evidence of water penetrating the concrete masonry unit walls in Rooms 114 and 115. This water has caused bubbles and deterioration of the paint on the CMU walls and will lead to more serious damage over time. The damage is evident in the pictures below. Picture 1 Room 115 Picture 2 Room 114 Partial Lower Floor Plan P:'PROJECTS\2010 \10039 \I PREDESIGN'REPORTRCC WATER INTRUSION STUDY.DOC Leaking along this wall The exterior of the building was also reviewed at the areas of interior leaking. First the areas above room 114 and 115 are shown in the pictures below. This is the area around the main south entry to the Rosemount Community Center. There are multiple visible issues contributing to the potential for water penetration. Each of these are listed next to the pictures. Picture 4 Scupper and planter P:NROJECTS'2010 I0029\1 PREDESIGNJ(EPORT WATER INTRUSION STUDY.DOC Pi. ;ture 5 Sidewalk to brick wall with cracked bricks Scuppers high on wall Slow drainage, trapped behind planter No movement joint with sealant at wall Cracked brick veneer Deteriorated mortar joints Through wall flashing not exposed at face of brick veneer No movement joint with sealant at wall Past Studies and Repairs CNH Architects was hired back in 2005 by the Minnesota Department of Military Affairs to review the National Guard Armory end of the Rosemount Community Center building. This portion of the building was experiencing water intrusion at that time. We provided a three step review of the areas of water intrusion including the following test methods: 1. Visual inspections 2. Thermal imaging showing brick wall moisture levels 3. Physical test opening of wall system Seeing this is the same building built by one contractor all at the same the issues discovered on the NGA end of the building will likely by si facility. This assumption is supported by the visual inspection done at portion of the building we found one major moisture control issue and The largest issue we found was with the through wall flashing at the base of the brick veneer walls. This flashing is typical for a cavity wall system such as that used for this building. The through wall flashing starts at the inner surface of the supporting wall, extends down 8' or more, transfers horizontally across the air gap between backup wall and brick veneer, and then extends out to the face of the wall. This flashing is intended to gather any moisture that gets through the brick veneer and channel it out of the building at the base of the wall. What we found is that the through wall flashing stops about an inch in from the exterior face of the brick veneer. This then gathers the moisture in the cavity, but instead of directing to the exterior it releases it into the brick bed joint and in some cases into the core openings in the brick itself. The water then runs down inside the brick, hits the bond beam at the precast plank floor bearing and soaks the concrete block from there down. A sketch of this condition below shows the intrusion path. Water Intrusion Sketch Main water entry point P:\PROJECTSl2010\10029\I PREDESIGN REPORPRCC WATER INTRUSION STUDY.DOC time, I would anticipate that milar along the rest of the this time. For the NGA several contributing factors. Water spreads at bond beam creating moisture from this point down The other contributing factors noted on the National Guard Armory portion of the building included the following items. Poor grade drainage away from the building allowing water to gather near the building during stronger rainfalls. Insufficiently sized splashblocks at scupper locations not directing water away from the building quick enough. Scuppers higher on wall than usual causing splashing. Overflow scuppers near top of walls leading from drains that were flush with the roof system instead of up to 2" above the roof as allowed by code. This resulted in water running out of the overflows at all times, instead of only when the main roof drains were overloaded or plugged with debri. Poor connection of the below grade waterproofing to the top of ground allowing gathered moisture to wick into the building below the through wall flashing. It is my opinion that most of the items listed above also contribute to the moisture problems currently experienced here as well. I would also add that the sealant at the brick control expansion joints going vertically up the walls is showing signs of exceeding its life expectancy. Several areas show cracking of sealant and in two cases the sealant has lost its bond to the brick on one side of the joint. This joint sealant failure will lead to excessive water penetration into the wall cavity and eventually additional penetration into the interior. P:U'ROIECTS'20I0N0029\I PREDESIGNREPORTULCC WATER INTRUSION STUDY.DOC Recommended Remedial Actions CNH Architects recommends the following remedial repairs to address the water intrusion currently occurring. The measures listed were successful at resolving the moisture problems at the National Guard Armory portion of the building. Brick Wall and Sidewalk Open base of wall and install new through wall flashing extending out to face of wall. Add strip of waterproofing membrane between current membrane and the bottom of the metal flashing. Add stainless steel counterflashing between through wall flashing and below grade. Replace sidewalks along building both for added joint at wall as well as to improve rainwater flow away from building. Provide a flexible joint filler and sealant joint at the top of any areas with sidewalks. Rainwater Scuppers Install large concrete splash blocks at scupper locations in lawn area. Add 2" pipe extension at overflow roof drains. Knee Wall at Translucent Panels Remove existing caulking. Install new caulking. Repaint caulking and trim. Control Expansion Joint Caulking Remove existing caulking and rod at existing joints. Install new caulking and rod at existing joints. P:IPROJECTS20104002911 PREDESIONREPORTRCC WATER INTRUSION STUDY.DOC Remove and replace sidewalk Replace through wall flashing, 3 walls (102 If) Conclusion The water intrusion being experienced in the lower levels of the building appear to be from the same causes previously discovered and repaired on the National Guard end of the building. The remainder of the water intrusion is from sealant joints that have reached their life expectancy. The water intrusion will continue at current or increased levels if not addressed and will lead to deterioration of concrete masonry unit walls, mortar joints, and interior finishes. The high moisture levels will also provide increased risk of mold growth. The repairs indicated should resolve the moisture issues as they have done in the previous work. On behalf of CNH Architects, thank you for the opportunity to provide this review. I look forward to continuing to assist the City of Rosemount. Best Regards, Quinn S. Hutson, ALA, LEED AP Reg. No.: 21234 Principal CNH Architects, Inc. P: PROJECTS12010`.10029U PREDESIGN'REPORrRCC WATER INTRUSION STUDY. DOC