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HomeMy WebLinkAboutAnderson Windows glass performance - Oak Park Heights Facility Wk G1 �'SS (�ro�tr� (Wt'( 7 F3UETOW AND ASSOCIATES INC !N ARCHITECTURAL SERVICES COMPANY 2345 Rice Street Suite 210 St. Paul, Minnesota 55113 z August 19, 2010 Andersen Wood Windows Glass Memorandum To: Eric Johnson, AICP, City Administrator From: Randy Engel, Principal -in- Charge RE: Oak Park Heights City Hall 14168 Oak Park Boulevard North " Oak Park Heights, Minnesota 55082 BA #0822 1.0 Jorgenson Construction has advised that its Wood Window Subcontractor has installed Andersen Windows that each contains Andersen HP Clear Low E 4 tinted glass (hereafter described as "installed glazing ") manufactured by Cardinal Glass rather than the specified Viracon VE2 -55 Low E tinted glazing. 2.0 Thirty -three wood window units of different sizes and configurations are involved (9 %± of exterior wall surfaces): • North Elevation: 10 units 0 • East Elevation: 6 units • South Elevation: 3 units • West Elevation: 8 units • Corners: 4 units • Clearstories (East and West Elevations): 2 units 3.0 Attached is a "glass performance memo" received from Jay Sandgren of Andersen Windows (dated August 10, 2010) that responds to the Architect's request for published performance characteristics for the HP Clear Low E 4 tinted glazing. 0 4.0 The individual glass panel of the "installed glazing" is thinner than the specified product: 7/32" rather than 8/32 ". 5.0 The performance characteristics of the "installed glazing" are not equivalent to the specified glazing insofar as energy performance: The "installed glazing" allows more heat and light to penetrate into the building. Generally speaking, the energy performance of "installed glazing" is 50% less than that of the specified glazing. a (continued) � 1 0 li a tel 651 483 -6701 fax 651 483 -2574 www.buetowarchitects.com Andersen Wood Windows Glass Memorandum of August 19, 2010 Oak Park Heights City Hall BA #0822 6.0 The Warranty of the "installed glazing" is a slight improvement: 20 years against seal failure and stress cracks versus 10 years against seal failure by Viracon. Each of those respective warranties, however, is limited in extent since they each do not provide for costs /coordination of: glass removals, disposals, replacements labor and /or deliveries to the site. Furthermore, those limited warranties allow the manufacturer to either replace the glass or to refund the cost of the glass at the time it was purchased. Also, there are exclusions for such items as: improper initial installation, poor maintenance, cracks, scratches and /or use of cleaning agents. 7.0 A cost comparison is difficult to obtain inasmuch as those figures are proprietary with each respective Manufacturer. 8.0 Possible Options • Replacement of the glass in each window panel (except, perhaps, the unit(s) that was(were) recently replaced). Most likely, each entire window unit would be replaced. That would also likely require the removal /installation /replacement of interior portions of the wood trim, sill /stool and skirting. • An extended warranty on the glass and window units to, for example, 40 years. • A monetary settlement. • Accept the installation in place. The Possible Options discussed above are for review and consideration by the City of Oak Park Heights. One or more may be addressed to the General Contractor for their review, consideration and response. Subject: glass perfromance memo - andersen hp clear vs viracon ve2 -55 Date: Tuesday, August 10, 2010 5:16 PM From: Sandgren, Jay <jay.sandgren @andersenwindows.com> To: Randy Engel <randy_engel @buetowarchitects.com> Cc: "Pat J. Zahler" <PZahler @abc- cic.com> Conversation: glass perfromance memo - andersen hp clear vs viracon ve2 -55 Randy, Please find attached my letter regarding performance values for the supplied Andersen HP Clear low E 4 glass and the intended Viracon VE2 -55 product. We have verified glass make up and location along with researching the values for the product. I am also attaching Cardinal glass's product information on the" Neat" exterior coating which Andersen has named Low -E 4 that is on the exterior surface of the glass. Another factor to keep in mind is that our glass warranty is 20 years against seal failure and stress cracks — I believe Viracon's is 10 years at best and does not include stress cracks. Jay Sandgren, CSI. CDT Assoc. AIA Andersen Corporation Architectural Representative 524 Arthur Street Edina, MN 55343 TEL - 651 - 398 -4731 FAX - 651 - 275 -7662 jay.sandgren @andersencorp.com Think of the environment before you print! Page 1 of 2 Ande W INDOWS•DOORS �r 1 Memorandum Date: 8/10/10 To: Randy Engel Buetow and Associates 2345 No. Rice Street Suite 210 St Paul, MN 55113 From: Jay Sandgren, CDT, CSI Assoc. AIA Andersen Commercial Account Representative e-mail: jay. sand en@jandersencorp.com corp.con RE: Glass performance information — Oak Park Heights City Hall Randy, Listed below is performance data for the values you requested on the Andersen HP Clear low E 4 product, furnished in all of the main level vision areas of the city hall project. I have set up a comparison against values against Viracon's published values for the VE2 -55 1" insulated glass product that was intended to be used. Note that the Reflectance data is marked with * indicating that the information is taken from Cardinal Glass's performance charts and is not our own Andersen tested/published value. All numbers are center of glass Performance value Viracon VE2 -55 Andersen HP Clear 4 Visible light transmittance 40% 70% Reflectance 10 %exterior 1 1 % * exterior Performance value Viracon VE2 -55 Andersen HP Clear 4 16% interior 12% * interior U value 0.27 winter 0.25 winter Shading coefficient 0.29 0.46 Relative heat gain 62 95 Solar heat gain coefficient 0.25 0.40 Low E coating type argon fill low e dual coating argon fill Surface coating location #2 surface #2 surface Glass thickness Vs" 5.7 mm Overall IG thickness 1" nom 1" nom. Additional note — Andersen HP Clear low E 4 — has special unique exterior coating that reduces water spotting — Cardinal's "Neat" product which minimizes frequency of washing. (see separate data sheet on Neat coating). Please feel fre to contact me if you have any additional questions. _, Jay andgren Andersen Architectural Sales Representative Copy — Pat Zahler Arrow 2 ®Cardinar CG Technical Service Bulletin Bulletin # CGO5 — 1/06 NEATTM COATED GLASS The second generation of low maintenance glass products has been developed by Cardinal CG Company. The coating on this product is similar to Cardinal's first low maintenance glass coating, its LoE Plus coating, which was introduced to the market in 2003. Similar to the Loe Plus coating, NEATTM coated glass is produced by magnetron sputtering which provides a hydrophilic glass surface once fully activated by UV Tight. Unlike glass coated with the LoE Plus coating, NEATTM coated glass does not have a ZnO (zinc oxide) overcoat which must be removed in the field. The coating on NEATTM glass includes titanium dioxide (Ti02), applied over the # I outdoor glass surface, and is a photocatalytic coating. Being photocatalytic means that the coating absorbs UV light which in time leads to decomposition of organic residue on the glass surface. Features and benefits of NEAT"" coated glass products: • NEATTM coated glass products include a titanium dioxide (Ti0 functional film coating. The titanium dioxide thickness is below 100 Angstroms. • NEATTM coated glass products, when activated by UV light, have a surface contact angle below 25 °. Having a low contact angle means that water sheets off of the glass surface (called "hydrophilic" in this TSB) instead of beading up. Figs. CG 05 -01 and CG 05 -02 show the difference in high contact angle (beading up) and low contact angle (sheeting). The lower the contact angle, the better the sheeting action and less opportunity for water droplets to evaporate on the glass surface and leave airborne pollutants on the glass surface. • Although to date there are no industry standards on what is considered to be a hydrophobic or a hydrophilic glass surface, at lower contact angels i.e. 25° and below, water sheets. At high contact angles, water beads up (called "hydrophobic" in this TSB). B Low Contact High Contact � g Angle- Hydrophilic Angle-Hydrophobic a • • Fig. CG 05 -01 Beading up of water Fig. CG 05 -02 Sheeting of water 1 • The coating on NEATTM coated glass becomes active and hydrophilic after the NEATTM coated glass surface receives radiation from UV light. The UV radiation can be from direct or indirect sunlight. Even if first exposure to UV Tight is on cloudy days or with north facing windows, the coating will still become photoactive and perform; however, more time will be needed for activation than if the coating on the NEATTM glass is exposed to direct sunlight. • When NEATTM coated glass is used on the f 1 surface (outdoors) of a window, the window will stay cleaner longer because the NEATTM coated glass surface causes water to sheet off of the surface. Uncoated glass surfaces that are hydrophobic permit water to bead up on its surface. The sheeting action allows dirt to rinse from the glass surface rather than dry in highly visible ringlets or water marks. The beading up of water on non - coated glass and sheeting action of water on NEATTM coated glass is shown in Fig. CG- 05 -03. 0 C) �-. g 410 0 Jit ENO Hydrophobic Reaction Hydrophilic Reaction Uncoated Glass "^ Neat Fig. CG 05 -03 • NEATTM coated glass products provide a smoother glass surface, compared to pyrolytic photoactive coatings as shown by photomicrographs in Fig. CG 05 -04. A smoother surface as shown by this NEATTM photomicrograph makes the NEATTM product easier to clean. c.e..4 n. n NEATTM Photoactive Coated Glass Pyrolytic Photoactive Coated Glass Fig. CG 05 -04 Roughness comparison of the NEATT" coated glass surface and a typical pyrolytic photoactive glass surface. 2 • Due to its photocatalytic properties, the coating on NEATTM coated glass cleans itself of many non - mineral deposits i.e. light deposits of silicone vapor, adhesive residue, suction cup marks, fingerprints, organic pollution, pollens, resins, etc. • The coating on NEATTM coated glass performs well in all environments; whether dry, humid, cold or warm. • The coating on NEATTM glass decomposes: o Silicone vapor contaminations (one to six weeks depending on cloud cover, sun angle, length of daylight (etc). o Organic materials (pollens, resins, fingerprints and other organic pollutants). Thick layers may be partially decomposed, loosened and then rinsed away with water. o The film adhesive residue on PRESERVE glass units. o Vapors from many sealants i.e. Dow 1199, Silglaze, Novaflex, Dow 9 -1350 and Dow 3- 01 17. o Most organic deposits left on the glass from manufacturing i.e. suction cup marks and marks from glass riding on rollers and belts. • NEATTM coated glass has been tested for over 4,000 hours in a carbon arc ISO test standard and after this test, the contact angle remained at or below 20 degrees. 4,000 hours in this test is predicted to be equivalent to 13 years of field exposure. • NEATTM coated glass does not: - Decompose thick contamination i.e. silicone fingerprints, paint, stain etc. - Stop sealant bleeding after weathering. - Decompose silicone glazing residue or stop bleeding around the perimeter of a window which can cause moisture picture framing around the perimeter of a window as can be seen in Fig. CG 05 -04. Windows with a bed of silicone to adhere the sash to the glass on the outdoor #1 glass surface can result in a narrow residue area of higher contact area around the perimeter of the glass. This perimeter area usually extends into the vision area approx. 1" to 3" from the edge of the window. Sill section of window • showing water beading nirMilipmewisetomintiperort up due to silicone _*°.• glazing sealant residue on glass. Fig. CG 05 -05 — Silicone glazing residue causing picture framing 3 • NEATT"' coated glass can be tempered. • NEATT "' coated glass does not alter the color or performance of the glass. • Recertification for NFRC testing of NEAT' "' coated glass used in windows is not required because the coating on the NEATT "' glass does not affect: - Outdoor or Indoor reflections and visible transmittance - Solar heat gain co- efficient - U- Factor - Color This can be seen in the LoE -272 comparison chart below. Other LoE coatings will also have no change in performance with NEATT "'. IGU Performance NEATT"' with Lo IGU Description Vis. Vis Refl. Solar SHGC U UV UV Color Trans. Ext Ext. Refl Value Fading Trans. LoC -272 72% 11% 36% 0.41 0.25 34% 16% Neutral Neat w /LoE -272 on #2 72% 12% 37% 0.41 0.25 34% 16% Neutral o Glass construction 3E /1 1.5/3 with 90% argon fill level (3 mm glass, 11.5 mm airspace and LoE on the #2 glass surface) o Data is for center of glass PROCESSING NEATTM COATED GLASSES When fabricating IG units with NEATT "' coated glass, Cardinal recommends that the pH of the wash water be as neutral as possible and not be below 5.5. NEATT "' coated glass should be placed in the IG unit washer with the NEATT "' coated glass surface down and the LoE coated glass surface should be up and away from the rollers in the washer. When glazing, care should be taken to avoid direct sealant contact to the NEAT"' coated glass surface except as required in the glazing area. For grilles that are adhered to the #1 glass surface with a PSA glazing tape (as shown in Fig. CG 05 -06), if the glazing tape manufacturer recommends a primer be used on clear glass to adhere the PSA glazing tapes, it is also recommended that this same primer be used on the NEAT"' coated glass surface. 4 VHB Tape V � 9 \ rT Primer Primer NEAT Coating 1 Fig. CG 05 -06 — Grilles adhered to NEATT" coated glass. PROTECTION AND CLEANING OF NEATT"' COATED GLASS When NEATT "' coated glass is installed in a window in the field, normal glass protection should occur to reduce the opportunity for building materials (i.e., stucco, paints, stains, etc.) used at the job site from contacting the glass surfaces. Thick deposits or layers of these materials will not be removed by the photocatylic action of the coating on NEAT"' coated glass. Usually contractors use plastic sheeting or polymer films to protect the glass from standard construction materials. No special cleaning requirements are necessary to clean NEAT" coated glass. Standard cleaning solutions such as a soap solution with clean water or standard window cleaning products can be used. As with standard glass products, if a squeegee is used to clean the glass, the squeegee should not have any metal edges exposed as the metal edges could scratch the coating or glass itself. As with non - coated standard glass products; metal blades should not be used as they will scratch NEAT" coated glass just as they will scratch any glass product. Clean NEATT coated glass on a regular schedule as needed. In most applications this will be needed less frequently than without NEATT coated glass, however, in areas where rainfall does not reach the surface, NEATT coated glass cannot rinse clean. Hard water deposits are visible (less visible than on uncoated glass) and are reduced after contact with rain or washing. Automatic sprinklers should be adjusted to prevent sprinkler water contact. When first installed, it will take time for the coating on NEATT coated glass to become fully active. Based on weather patterns and the amount of UV available for activation of the coating on NEATT coated glass, the attached U.S. maps show the approximate times for full activation of the coating on South and North exposures in the Spring /Fall and Autumn /Winter yearly cycles. 5 FULL ACTIVATION - Activation without screens or overlays South Face: Spring /Summer South Face: Autumn/Winter f .r i 8 week s / p � ''e/ � ' 1 1� ' '—r— 4 ,.----1 umi -- .46., 3weeka ,� w mil— , ,l ����� More than \ 3 weeks 8 weeks ti \, \ f, 'r 2 weeks North Face: Spring /Summer North Face: Autumn/ Winter QT '° c apillilrair- BW EEK�� � f III/' m ORE THAN �� =� 4? e WEEKS '� N. 1•a t3WEEKS —�w -- 4111L0 4.... - \ ,_ 2 WEEKS �_.� �� 4 WEEKS —4 .w � Pi C . " . I WEEKS 3 WEEKS Factors that can affect NEATTM coated glass performances are: • Screens • Elevations /orientations • Vegetation • Volatile Organic Compounds (VOC's) Accelerated UV and condensation exposure testing indicate that sheeting and photoactivity of NEATT" coated glass should continue after 15 years of exposure. NEAT"' AND PRESERVE COATED PRODUCTS Cardinal's PRESERVE glass products include a protective film used on the exposed glass surfaces of IG units. Cardinal IG Company owns several patents relevant to PRESERVE glass products. (see TSB IG 17- 07/10). NEATT "' coated glass is compatible with the protective film used on Cardinal's PRESERVE glass products. The protective film protects the PRESERVE` glass surfaces during shipping, window fabrication, handling and installation and from debris to which the glass is exposed on the jobsite. Use of the protective film will not significantly increase the UV light activation time of the coating on NEATT "' coated glass. 6