TO THE DRAWINGS AND THE PROJECT MANUAL

Transcription

1 NO. 1 TO THE DRAWINGS AND THE PROJECT MANUAL PROJECT NAME: Sealy Junior High Roof Replacement CLIENT NAME: Sealy ISD LOCATION: Sealy, Texas PROJECT NUMBER: PROPOSAL DATE: Monday, October, 17, 2016, Time: 2:00 PM ROBERT G. HO O PE R ADDENDUM DATE: Wednesday, October, 12, 2016 For additional information regarding this project, contact Brendon Hoffman at /12/2016 THIS ADDENDUM INCLUDES: Civil Items 0 Pages Landscape Items 0 Pages Structural Items 0 Pages Architectural Items 1 Page Foodservice Items 0 Pages Plumbing Items 0 Pages Mechanical Items 0 Pages Electrical Items 0 Pages Technology Items 0 Pages AND ALL ATTACHED REVISED DRAWING REFERENCES IN THE ADDENDUM

2 Project Name: Sealy Junior High Roof Replacement Client: Sealy ISD Sealy, Texas Project Number: ROBERT G. HO O PE R ARCHITECTURAL ITEMS FOR ADDENDUM NO. 1 NOTICE TO PROPOSERS: A. This Addendum shall be considered part of the contract documents for the above-mentioned project as though it had been issued at the same time and incorporated integrally therewith. Where provisions of the following supplementary data differ from those of the original contract documents, this Addendum shall govern and take precedence. B. Proposers are hereby notified that they shall make any necessary adjustments in their estimate on account of this Addendum. It will be construed that each Proposer s proposal is submitted with full knowledge of all modifications and supplemental data specified therein. Acknowledge receipt of this addendum in the space provided on the proposal form. Failure to do so may subject Proposer to disqualification. REFERENCE IS MADE TO THE DRAWINGS AND THE PROJECT MANUAL AS NOTED: PROJECT MANUAL: 10/12/2016 AD No 1, Arch. Item 1: To the Project Manual, Sections as listed below, Part 2 Products; Products listed herein are considered acceptable for conformance with the design concept of the project and general compliance with the information given in the contract documents. The manufacturer, supplier and installer are responsible for meeting all requirements given in the contract documents unless specifically noted in the written approval. 1) To Section , MECHANICALLY ATTACHED POLYVINYL-CHLORIDE ROOFING, Model 50 MIL PVC as manufactured by DURO-LAST AD No 1, Arch. Item 2: To the Project Manual, Section , AGREEMENT FORM, Replace Section with revised Section issued as part of this addendum. AD No 1, Arch. Item 3: To the Project Manual, Section APPENDIX INFRARED ROOF MOISTURE SURVEY, NOTE: THE SURVEY IS FOR REFERENCE ONLY. END OF ARCHITECTURAL ADDENDUM Architectural Items For Addendum No. 1 Page 1 of 1

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22 September 8, 2016 Mr. Chris Bent, AIA Huckabee, Inc Hughes Landing, Suite 701 The Woodlands, Texas Subject: Infrared Roof Moisture Survey and Roof Deck Fastener Withdrawal Resistance (Pullout) Test Report Sealy ISD Sealy Junior High Campus 939 Tiger Dr. Sealy, TX K&A Project No.: Dear Mr. Bent: Pursuant to your request, Kuhn and Associates, Inc. (K&A) performed an infrared roof moisture survey and pullout testing of the steel decks at the subject project during the month of August This scope of service was performed in accordance with K&A proposal number dated August 8, PROJECT INFORMATION The Sealy ISD junior high campus is a single story campus with multi-level roof areas. The existing roofing system appeared to consist of a spray-applied polyurethane foam (SPUF) roof over a gravel surfaced asphalt built-up membrane, rigid board insulation, and a lightweight insulating concrete over steel deck. As reported below, some of these decks were discovered to consist of a poured gypsum fill over a formboard substrate. In preparing for the pending roof recover construction, K&A performed an infrared roof moisture to ascertain possible areas of subsurface moisture, and fastener withdrawal resistance (pullout) test of the steel deck. This report presents our test methodology, test results, conclusion, and recommendation. 2.0 TESTING 2.1 Infrared Roof Moisture Survey A. Methodology The purpose of the infrared roof moisture survey will be to determine the existence of subsurface moisture within the roofing systems through the use of infrared thermography. This technique is based upon the ability of the equipment to detect variations in temperature radiating from the roof surface 4201 Cypress Creek Parkway, Ste 450, Houston, TX Phone: Fax:

23 Huckabee Sealy ISD Junior High Campus K&A Project No.: September 8, 2016 and to convert this into an electrical signal that is displayed in a video-heat image called a thermograms. The roof surface acts as a thermal collector and roof insulation laden with moisture absorbs this solar heat and retains it after the solar effect has dissipated. Heat loss from the roof surface during colder weather is also observed because wet insulation has a lower R-valve than the surrounding dry insulation, thereby differentiating wet areas from dry areas. Unlike other non-destructive techniques, the infrared equipment can scan every square foot of the roof surface including vertical flashings around the perimeter and under roofing appurtenances and equipment allowing a comprehensive review of the entire roof assembly. The optimum time to perform this survey is when the ambient temperature and the subsurface roof temperature are at their maximum differential. This typically occurs shortly after sunset. B. Test Results Thermogram Nos.: 1 6 Results of the infrared roof moisture survey indicate that subsurface moisture does exist on multiple roof levels. This moisture appeared to exist within the spray-applied polyurethane foam (SPUF) roof. The anomalies typically measured approximately 2 x2. The outlines of observed anomalies were spray painted on the roof surface, as well as approximate locations annotated on the roof plans presented in the Appendix of this report. Although a total of 35 anomalies were observed, not all 35 thermograms are presented in the Appendix of this report. Areas of subsurface moisture will need to be replaced with new, dry insulation prior to the roof recover installation. A copy of this roof plan will be presented to the contractors who will bid the pending roof recover project. 2.2 Fastener Withdrawal Resistance (Pullout) Tests Pullout tests were performed of the steel decks using 8 #15 screws as manufactured by OMG. K&A used our in-house Com-Ten Industries Model DFG1W1000 Pull Tester to determine pullout values. The pullout tests were performed in general accordance with ANSI/SPRI FX The purpose of these tests was to determine whether the steel deck can provide sufficient pullout resistance of a roof fastener (screw) to guard wind uplift. These tests do not nullify the need of the awarded contractor to perform his own tests prior to his commencing with the roof recover construction. Presented in the table below are the results of the pullout tests. Each test location is also annotated on the roof plan that is attached in the Appendix of this report. Table 1.0 Pullout Test Results Test Location Pull Results (lbs) P a g e 2

24 Huckabee Sealy ISD Junior High Campus K&A Project No.: September 8, 2016 Table 1.0 Pullout Test Results (cont d) Test Location Pull Results (lbs) Gypsum Fill and Formboard Decking During these tests it was noted that five (5) roof sections appeared to have gypsum fill and formboard decking (see annotated roof plan). This type of decking does not allow roof components to be mechanically secured to the formboard. Therefore, pullout tests were not performed of these decks. K&A s recommended scope of work over this deck type is presented below under Scope of Work. 3.0 CORE SAMPLING Core samples were taken of the various roof sections system to identify the components of the roof system. Our typical observations of the components comprising the roofing system are presented below CONCLUSION Component Steel Deck or formboard Lightweight Insulating Concrete or poured gypsum fill Approximately 2 rigid board insulation Asphalt built-up membrane Spray-applied polyurethane foam roof Based on the results of the pullout tests, the steel decks appear to be sufficient for installing a new roof system that will be mechanically attached to the steel deck. However, with regard to the gypsum fill and formboard deck, it is K&A s opinion that this system cannot provide proper fastener resistance and, therefore, will require the roof recover scope of work to be modified over this deck. See Scope of Work below. P a g e 3

25 Huckabee Sealy ISD Junior High Campus K&A Project No.: September 8, SCOPE OF WORK Based on the information presented above, provided below is our recommended scope of work for both deck types. These scopes of work include, but may not be limited to, the following: A. Steel deck 1. Scarify existing SPUF down to level and sound substrate. 2. Replace wet insulation with new, dry insulation. 3. Loose lay cover board over scarified SPUF. 4. Mechanically attach cover board to steel deck. 5. Install single ply membrane mechanically attached to the steel deck. 6. Install fasteners at spacing or density required to meet wind uplift ratings. B. Gypsum fill and formboard 1. Scarify existing SPUF down to level and sound substrate. 2. Replace wet insulation with new, dry insulation. 3. Set cover board in low-rise foam adhesive directly to scarified SPUF. 4. Set single ply membrane in bonding adhesive. 5. Apply adhesive at rates required to meet wind uplift ratings CLOSE Our conclusion and recommendation were based on the results of the infrared roof moisture survey and of the fastener pullout tests. Unobservable conditions may exist that may negatively affect our conclusion, recommendation, and general scope of work. K&A appreciates this opportunity to work with you on this project. Please call should you have any questions, comments, or concerns. Sincerely, KUHN AND ASSOCIATES, INC. Robert G. Kuhn, RRC Senior Consultant Attachments: Thermograms Roof plans P a g e 4

26 APPENDIX

27 Huckabee Sealy ISD Junior High Campus K&A Project No.: September 8, 2016 Thermogram No.: 1 Anomaly observed on hallway roof area. Thermogram No.: 2 Anomaly observed on northeast roof area. Thermogram No.: 3 Anomaly observed on main field of roof.

28 Huckabee Sealy ISD Junior High Campus K&A Project No.: September 8, 2016 Thermogram No.: 4 Anomaly observed near field drain. Thermogram No.: 5 Anomaly observed on main field of roof. Thermogram No.: 6 Anomaly observed on north roof area. P a g e 7

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