Attachment_1_-_Statement_of_Work.docx

National Park Service U.S. Department of the Interior

Chesapeake and Ohio Canal

REPAIR AND REPLACE ROOFS AT GREAT FALLS TAVERN AND PUMP HOUSE

AT 11710 MACARTHUR BLVD.

POTOMAC, MD 20854

CHESAPEAKE AND OHIO CANAL NATIONAL HISTORICAL PARK

PMIS NO. 245021 and 258109 Contract No. XXXXXX

SCOPE OF WORK FOR ROOF REPAIR AND REPLACEMENT

Background:

The National Park Service (NPS) owns and operates the Great Falls Tavern in Potomac, MD, along with ancillary structures on site, including the Pump House, east of the Tavern. The Tavern was built in 1828 as a part of the initial construction of the Chesapeake and Ohio Canal, as one of many typical lock keeper’s houses located along the canal. As construction ended in 1830, however, the Canal Company recognized that the scenic grandeur of Great Falls would draw tourists and decided to build an addition onto the lock keeper’s house to create a hotel and tavern, which were completed in 1831. The building continued to operate as a house of hospitality, off and on, until 1938, when the NPS acquired it and now uses it as a museum and Visitor Center for the area. The adjacent Pump House was built in the 1930’s by the Civilian Conservation Corps to house equipment to pump water for the Great Falls area. The existing wood shingle roofs on these buildings were installed around 2010. Work will include removing the wood shingle roofs from both structures, replacing rotted sheathing and trim and reinstalling new cedar shingle roofs on both buildings. The contractor shall provide a proposal to meet the objectives of the National Park Service, and work must be performed utilizing historic preservation methodology.

Project Description:

· At the Tavern, remove the wood shingle roof, remove water-damaged sheathing (assume 25% replacement), and water-damaged soffit and fascia. Remove and retain the gutters and rainwater leaders as needed to proceed with work. Install replacement sheathing, wood shingle, waterproofing and soffit and fascia. Reinstall the gutters and leaders.

· At the Pump House, remove the rotted shingle roof and water damaged skip-sheathing (assume 65% replacement), waterproofing, soffit and fascia. Install new skip-sheathing, a new wood shingle roof, and new soffit and fascia. Some repair work will be required to the roof trusses at the Pump House.

General Provisions

1.1. The contractor shall provide all management, supervision, labor, materials, supplies, tools, equipment, scaffolding, and all other items needed to coordinate and ensure quality workmanship.

1.2. The contractor shall take into consideration the use of existing ancillary equipment, building support systems, and operating environment in order to achieve the objective.

1.3. The contractor shall take care as to not damage existing infrastructure. The contractor shall be held liable for cost of all repairs to existing infrastructure that result from the performance of this contract. There are no above-ground utility lines connecting to either of these structures.

1.4. Contractor shall include all necessary parts, materials, products, and all ancillary components required for a complete, safe, reliable, and functional building, even though each item/device is not specifically mentioned or described herein.

1.5. The determination of the total daily productive man hour requirements, and total quantity of materials for the performance of all construction specified herein is the sole responsibility of the bidder. It is of the utmost importance that the contractor utilizes skilled and productive manpower in order to satisfactorily furnish the required level of service specified in this contract.

1.6. Quality workmanship is required at the full performance level of specified construction, beginning at the contract start date.

1.7. The contractor shall take into consideration the potential existence of unknown structures, utilities, and ancillary infrastructure.

1.8. The contractor shall be responsible for professional quality, technical accuracy, project coordination, material installation, disposal of existing materials, and all other ancillary items required to deliver and handover a complete building to the NPS.

1.9. The contractor shall provide all necessary supervision, safety protection devices, and personal protective equipment (PPE), required for complete and safe operations on site. Protective measures shall prevent injury to the public, Federal employees and contractors, visitors, Contractor’s employees, and damage to or contamination of surrounding property and/or the environment.

1.10. All work shall be performed between the hours of 0600 and 1630 during the normal 5 day workweek, Monday through Friday, Federal holidays excluded, unless specifically approved by the COR. Work to be performed on weekends must be scheduled at least 48 hours in advance with written approval from the COR. Scheduling of all work must be approved in writing by the COR. Required shutdown of utilities or building areas shall be scheduled with the COR at least 48 hours in advance so that building operations are not disrupted.

1.11. Contractor shall investigate existing conditions, review any applicable specification, and make necessary calculations, recommendations, and modifications to achieve the objective of the NPS. Contractor proposal is to be “all encompassing” to return building to complete working condition upon contract completion.

1.12. Contractor is responsible for obtaining any and all required permits and meeting all OSHA and industry regulations that apply for working on roofs, and working around/with electrical equipment. Contractor personnel shall possess and maintain all required certifications, contractor is responsible for ensuring that appropriate certifications are in place.

1.13. Contractor shall research and verify, and at all times comply with all applicable laws, life safety codes, ordinances, rules, regulations, and orders of authority having jurisdiction.

1.14. No welding or hotwork is anticipated as a part of this scope. Hotwork requires a separate NPS permit. Alert the Contracting Officers Representative (COR) as soon as possible if hotwork is planned.

1.15. Contractor shall coordinate and dispose of all refuse materials. Worksite is to be maintained in a tidy manner, with debris removed each day. A dumpster may be staged on site at a predetermined location for the duration of work. Contractor shall ensure that job site is free of construction debris, especially nails, during the course of and at the completion of the project.

1.16. NPS does not provide for storage of contractor materials or equipment on site. Any materials left overnight are responsibility of contractor. The work area is not secured.

1.17. Contractor must field verify all quantities and dimensions affecting the work of this contract, and must field verify all new and existing dimensions affecting the work of this contract.

1.18. Contractor shall protect all exposed surfaces from adverse weather conditions during course of work to prevent water infiltration and damage to existing structure.

1.19. All work, including contact with and handling of hazardous materials, the disturbance or dismantling of structures containing hazardous materials, and/or the transport and disposal of hazardous materials shall comply with the applicable requirements of 29 CFR 1910/1926, and 40 CFR 761/260-271.

1.20. Smoking will not be permitted within 100 yards of park buildings and may only be permitted in area designated by the Park Superintendent.

1.21. COVID-19 Awareness: The contractor is to provide safe on-site working conditions for their employees working on and visiting NPS property. All work shall be performed in accordance with all applicable local jurisdiction orders, federal orders, and the CDC’s guidance and recommendations related to best safety practices during the COVID-19 pandemic. https://www.cdc.gov/coronavirus/2019- ncov/community/index.html.

2. Proposal Requirements – The Contractor shall provide a proposal to complete the following work:

2.1. Work shall be performed on the Great Falls Tavern and Great Falls Pump House, at 11710 MacArthur Blvd., Potomac, MD

2.2. Project Materials:

2.2.1. Roofing Shingles: New Western Red Cedar 18” Perfections Number 1 Blue Label shingles, premium grade with 100% heartwood, 100% clear and 100% edge grain. All shingles are to be pressure treated. All bundles of shingles will be as manufactured and graded only by a Cedar Shake and Shingle Bureau (CSSB) member with attached Certi-Label and Certi-Last labels. Shingles will be installed per CSSB standards with a double starter course, 5.5” exposure and 316 stainless steel ring shank single nails, 2 per shingle.

2.2.2. Use No. 30 ASTM D226 Type II or No. 30 ASTM D4869 Type IV asphalt saturated organic roofing felt.

2.2.3. Use 16 oz/22 mil. lead coated copper for all flashings. Flashings to be installed as indicated in the CSSB manual Figure 13c. Projections through the roofs to be flashed as per CSSB Manual Figures 14a and 14e.

2.2.4. Use 316 stainless steel fasteners unless otherwise noted.

2.2.5. All exterior trim board lumber will be of “Select” grade.

2.3. Great Falls Tavern

2.3.1. Wood shingled area approximately 3,800 sf. The Tavern was enlarged several times, so the roof has several different sections, with three dormer windows, different slopes and details.

2.3.2. Work does not include the one-story standing seam copper porch roof on the west side of the structure. Protect that section of roof from damage during work.

2.3.3. Remove existing roof

2.3.3.1. Remove all wood roof shingles, ridge vents, and flashings. Remove rotted wood sheathing, rotted soffit and fascia, and rotted rake boards (assume 25% of total).

2.3.3.2. At the three dormers, remove wood shingles on the roof, wood shingles on the cheek walls. Remove rotted wood sheathing on both the roof and cheek walls (assume 25% of total). Remove rotted soffit and fascia, as well as rotted elements on the face of each dormer, including the pediment, engaged pilasters and louvers.

2.3.3.3. The gutters and leaders are in good condition. Remove and salvage gutters, gutter hangars, brackets and any parts of the rainwater leaders needed to complete roofing work and retain them for reinstallation.

2.3.4. Install a new, weather-tight wood shingle roof at Great Falls Tavern.

2.3.4.1. Replace dimensional wood lumber sheathing in kind (assume 25% of total area). Replace wood sheathing at dormer cheek walls in kind (assume 25% of total area). New roof sheathing will be attached with a minimum of two nails per rafter crossing or a maximum 3” spacing across the width of the plank using 8d or 10d nails based on the dimension of the plank (1 1/2 “ nail penetration into rafter). Loose or unattached boards will be re-attached with the specifications listed above.

2.3.4.2. Install 2x4 spacers and 1x4 nailing strips atop the solid wood decking, as per Figure 3 from the Cedar Shake and Shingle Bureau Manual (CSSB) attached). New dimensional lumber to be pressure treated.

2.3.4.3. Install roofing felt. At the eaves, roofing felt is to be 36” wide, starting at the bottom edge of the eave. At parapets, and chimneys, felt is to be 11” wide on both surfaces. On dormer cheek walls, felt is to be 11” wide on the roof, and stapled the full height of the cheek wall. If the felt is not wide enough to cover the full area, there is to be a 2” overlap between sheets.

2.3.4.4. Install roofing shingles (type as indicated in Section 2.2.1), following CSSB guidelines on page 5 of the CSSB manual (See Figure 5a). Shingles are to be doubled at all eaves. Butts of the first course should project 1-1/2” beyond the fascia, and 1” over the gable end where applicable. Spacing between the adjacent shingles should be between ¼” and 3/8” wide. Side lap to be not less than 1-1/2” inches, and not more than 10% of the joints shall be in direct alignment in alternate courses.

2.3.4.5. Install new wood shingles at the dormer cheek walls, replicating the existing pattern, with two square-cut courses at the top of the wall, three courses of hexagonal-cut shingles below, and then approximately six square-cut courses below, filling the lower portion of each wall. Work to comply with the CSSB Sidewall Installation Manual (attached).

2.3.4.6. At all hips and roof ridges (including at dormers), install roofing felt, ridge ventilation product with shingles above. See Figure 16 in the CSSB Manual to guide installation. Roof and dormer caps will be hand assembled on site with project-specific shingles, and not pre-fabricated.

2.3.4.7. Install flashings as directed in the CSSB Manual and the CSSB Sidewall Installation Manual. See CSSB Manual Figure 14c for direction on flashing around chimneys and parapet walls. See Sidewall Installation Manual Figure 3a for flashing at dormers.

2.3.4.8. Reinstall salvaged soffit and fascia. Where elements are too deteriorated to be replaced, install new elements that match the existing in wood type, dimension and cut. New exterior wood components will be painted with one oil based primer coat (including back-primed) and two top coats of flat acrylic paint matching the existing trim at the Tavern, for a total of three coats on exposed wood surfaces.

2.3.4.9. Each new channel in the roof, formed by the spacers nailed into the solid sheathing, must be vented. At the eaves the new depth of the roof is to be stopped by dimensional lumber painted to match the white elsewhere on the building, but there should be screened vents between each spacer, sized to equal 1:150 of the area vented.

2.4. Great Falls Pump House

2.4.1. The Pump House is a two-story structure, approximately 20’x 28’, banked into the side of a hill. Constructed in the 1930’s by the Civilian Conservation Corps, the structure has a single end-gable roof, and a one-story shed roof on the north façade, with a chimney rising on the south end of the structure. The total area of wood shingles is approximately 650sf.

2.4.2. Remove existing roof:

2.4.2.1. Remove all wood shingles on gable and shed-roof sections of the building, remove all vents and flashings. Remove rotted skip-sheathing below (assume 65% replacement), and rotted wood soffits and fascia.

2.4.2.2. Examine roof trusses for rot, determine members that no longer retain structural capacity.

2.4.3. Install a new, weather-tight wood shingle roof at Great Falls Pump House.

2.4.3.1. Sister roof trusses that no longer retain structural capacity.

2.4.3.2. Replace rotted skip-sheathing in kind (assume 65% replacement).

2.4.3.3. Install roofing felt, type as indicated in Section 2.2.2. Roofing felt to be 36” wide at the eaves. At chimney, roofing felt to be 11” overlapping on either face.

2.4.3.4. Install roofing shingles (type as indicated in Section 2.2.1), following CSSB guidelines on page 5 of the CSSB manual (See Figure 5a). Shingles are to be doubled at all eaves. Butts of the first course should project 1-1/2” beyond the fascia, and 1” over the gable end where applicable. Spacing between the adjacent shingles should be between ¼” and 3/8” wide. Side lap to be not less than 1-1/2” inches, and not more than 10% of the joints shall be in direct alignment in alternate courses.

2.4.3.5. At all hips and roof ridges (including at dormers), install roofing felt, ridge ventilation product with shingles above. See Figure 16 in the CSSB Manual to guide installation.

2.4.3.6. Install flashings as directed in the CSSB Manual. See CSSB Manual Figure 14c for direction on flashing around chimneys.

2.4.3.7. Reinstall salvaged soffit and fascia. Where elements are too deteriorated to be replaced, install new elements that match the existing in wood type, dimension and cut. New exterior wood components will be painted with one oil based primer coat (including back-primed) and two top coats of flat acrylic paint matching the existing trim at the Pump House, for a total of three coats on exposed wood surfaces.

3. Requirements

3.1. Project Requirements:

3.1.1. The existing historic structure is not designed for heavy loading. Do not place heavy equipment or store materials on roof.

3.1.2. Apply roofing only in dry weather. Do not apply roofing materials during precipitation or in the event there is a possibility of precipitation during application. Take adequate precautions to ensure that materials, applied roofing, and building structures are protected from possible moisture damage or contamination.

3.1.3. The slope of the main roof is steep and safety protection must be used when working at the project site. All work shall be conducted according to 29 CFR 1926 Subpart M - Fall Protection.

3.2. Warranty

3.2.1. The contractor shall warranty all materials, parts, and labor provided under the terms of the scope of work for five years from the date of completion and acceptance by the government.

3.2.2. The contractor shall furnish the NPS with all manufacturer warranty information for materials and parts provided under the terms of the scope of work.

3.2.3. All materials not covered by the above warranty shall carry a ten-year warranty.

3.3. Submittals

3.3.1. Before any work commences, the COR must approve all submittals.

3.3.2. Product Data:

3.3.2.1. Submit manufacturer’s data for all materials.

3.3.2.2. Product data shall include technical specifications, instructions for application and use, and Safety Data Sheets (SDS).

3.3.3. Material Samples:

3.3.3.1. Submit full documentation on the source and grading of the wood shingles.

3.3.3.2. Submit samples of lead-coated copper and felt.

3.3.4. Plan Documents (prior to commencement of work)

3.3.4.1. Detailed work plan – must include proposed timeline, methodology of work to be performed, and any other pertinent data necessary for complete repairs.

3.3.4.2. Site safety plan.

3.3.4.3. Building protection plan.

3.3.4.4. Site staging – must identify proposed staging of sanitary facilities, equipment storage, material storage, construction fence, refuse receptacle, dumpster requirements, etc.

3.4. Quality Assurance

3.4.1. All work shall meet IBC, NFPA 101, NFPA 72, NFPA 13, NFPA 70, and other applicable codes, standards, and building codes.

3.4.2. Contractor performing the work of this Section shall have at least ten (10) years of experience in wood roofing and shall have completed at least three (3) projects of similar scope and scale within the previous five years.

3.4.3. All work shall comply with the Secretary of the Interior’s Standards for the Treatment of Historic Properties, and the Secretary of Interior’s Standards for Rehabilitation and Guidelines for Rehabilitating Historic Buildings.

3.4.4. The Contractor shall utilize the most stringent code requirement, regardless of the code source or the version adopted by a jurisdiction.

3.5. Supplies, Materials, and Equipment

3.5.1. The contractor shall furnish all supplies, materials and equipment necessary for the performance of the work of this contract. As a minimum, these supplies and materials shall be of a quality to conform to all applicable Federal specifications. Before beginning the work of the contract, the Contractor shall submit to the Contracting Officers Representative (COR) a list, giving the name of the manufacture and the brand name of each of the materials that he/she proposes to use in the performance of the work. The Contractor shall not use any materials which the COR determines would be unsuitable for the purpose or harmful to any part of the buildings, the contents, equipment or persons. The Contractor shall submit a Material Safety Data Sheet (MSDS) for all materials to the Park Safety Officer for approval prior to use in the park.

3.5.2. Electrical power will be furnished by the Government at existing power outlets for the Contractors use to operate such equipment as is necessary in the conduct of his/her work. The Government will not be responsible for the contractor exceeding the recommended electrical load rating or tripped breakers that would prevent the contractors from performing the work. It is recommended that the contactors use portable generators to operate such equipment as is necessary in the conduct of his/her work.

3.5.3. Non-potable water will be furnished by the Government.

3.5.4. The Contractor shall provide cellular phones to their supervisor or foreman for business calls to the Contractor or to the COR. The Contractor shall provide contact information to the COR. (Consider taking the previous statement out) Maybe it should read “Contractors shall provide the site supervisor contact information to the CO and COR. Contact information should include office and mobile phone number and email address.”

3.6. Safety and Health

3.6.1. The Contractor shall submit a job specific safety plan for NPS approval prior to the start of work.

3.6.2. The Contractor shall at all times comply with Accident Prevention and Safety Requirements as outlined per contract specifications. In addition:

3.6.2.1. The Contractor shall conduct his/her operations to prevent accidents, injuries and damages; shall observe all fire, safety and traffic regulations. The Contractor shall provide all PPE including but not limited to rubber gloves, face masks, safety shoes/boots, hard hats and eye and ear protection as required under the documented Safety Plan and by product manufacturer's recommendations. The Contractor shall also be responsible for all safety communication and training requirements for the safe use of all equipment and materials. All protective equipment must meet ANSI standards and used as required by OSHA and as directed by the COR.

3.6.2.2. The contractor shall comply with all pertinent provisions of the Occupational Safety and Health Administration (OSHA) Standards, 29 CFR 1910, and 1926; the National Fire Protection Association (NFPA). Work shall conform to the latest edition of the International Building Code (IBC) and family of International Codes including but not limited to: International Plumbing Code, International Electrical Code and International Mechanical Code; work shall conform to the Life Safety Code.; ANSI; and any pertinent federal and local codes and requirements. All OSHA requirements may be obtained without cost to the general public at www.osha.gov . The Contracting Officer (CO), Safety Officer or Risk Manager may include additional measures if determined necessary or required by other Federal, State or local law, or park policy.

3.6.2.3. The Contractor shall have a Hazard Communication Program in place as required by 29 CFR 1910.1200 where Safety Data Sheets (SDS) / Technical Data Sheets shall be obtained by the contractor for all hazardous materials to be used in the performance of this contract. This plan shall be furnished to the NPS prior to the start of work. These SDS’s and an inventory of hazardous materials must be provided to the CO or COR prior to bringing the material on site. SDS shall be maintained at any jobsite where a substance requiring a SDS is being used. These SDS will be available to all employees of the Contractor, employees of the Park, concessionaires and the public when any member of these groups might come in contact with, or be exposed to, any substance requiring a SDS due to its hazardous status.

3.6.2.4. In the event of a reported physical injury, repeated service interruption, or an accident involving damage or equipment fire has occurred, the Contractor shall immediately secure the site and notify the COR and the NCR communications Center (866-677-6677).

3.6.2.5. In the event the contractor becomes involved in any incident or accident involving a Park Visitor, or Park Property, the contractor must notify both the COR and USPP, so an investigation and record can be made. All damage to government property caused by the Contractor shall be reported to the COR and the NCR communications Center (866-677-6677).

3.6.2.6. Contractors are subject to safety inspections performed by Park personnel or others. These inspections may be routine, unannounced, or based on reports of unsafe or unhealthy working conditions. Safety violations will be reported to the CO and Safety Officer. If a violation is deemed to be immediately dangerous to health, life, or serious in nature, the COR or any park officer at the Division Chief level or higher, has the authority to stop work until the matter may be resolved to the CO’s satisfaction.

3.6.2.7. NPS personnel do not issue confined space entry permits to contractors or provide equipment to evaluate confined spaces.

3.7. Environmental Requirements

3.7.1. The Contractor shall comply with all existing Federal and Maryland regulations pertaining to hazardous material use, storage and disposal. Materials and chemicals shall be stored, used and disposed of in such a manner as to not endanger or threaten the environment and the health and safety of the Maryland, Park employees and visitors. All generated waste shall be disposed of legally at the completion of each day's work, and shall be the responsibility of the contractor. Dumpsters and other waste disposal arrangements will be made separately from those used by the NPS for daily operations.

3.7.2. The Contractor shall comply with Executive Order 13693, pertaining to Sustainability, work shall incorporate the following: Construct or renovate buildings in accordance with sustainability strategies, including resource conservation, reduction, and use; siting; and indoor environmental quality. Reduce water consumption intensity. Purchase (specify) environmentally-sound goods. Reduce waste and implement recycling programs.

3.7.3. The Tavern was substantially rehabilitated, and no asbestos or lead based paints are known to be present in the project work area. Any area found to be containing these materials shall be brought to the immediate attention of COR. Activities shall cease and appropriate testing shall be conducted.

3.8. Qualifications, conduct and appearance of Contractor's employees

3.8.1. All Contractor's employees must be able to communicate in the English language with the Government's representative.

3.8.2. The Contractor shall require their employees to comply with the instructions pertaining to conduct and building regulations issued by duly appointed COR.

3.8.3. The Contractor shall be required to remove personnel in its employment on this contract for the following reasons:

3.8.3.1. Disrespect to either park employees or visitors during performance of the contract.

3.8.3.2. Personal conditions. Using illegal drugs, drinking alcoholic beverages, intoxicated behavior or unsafe work habits.

3.8.3.3. Misconduct of any kind.

3.8.4. Under circumstances set out in paragraph 3.7.3 above, the contractor shall be responsible for immediate removal of his/her employees. When it is necessary to remove personnel, the contractor shall immediately furnish a replacement/replacements to carry out the work to be performed under this contract.

3.8.5. The Contractor's employees shall wear a shirt, coveralls, or other uniform item of a distinctive color bearing his/her identification. Uniform shall bear the Contractor’s name or logo. Employee clothing shall be kept reasonably clean and neat in appearance.

3.8.6. There is no parking available on site. Contractors and contractors workers may park in the visitor use parking lot located in Great Falls, Potomac Maryland.

4. Pre-Work Conference

4.1. A pre-work conference will be conducted between the National Park Service Contracting Officer (CO) and the Contractor prior to the beginning of the work. The Contractor shall designate in writing at this meeting the names, telephone numbers, and addresses of all supervisors. The Contractor or his/her supervisor shall be available at all times when the contract work is in progress to receive notices, reports or requests from the CO or the COR.

4.2. The contractor shall provide to the COR a complete list of all employees under this contract. The list shall include individual tours of duty and schedules of work assignments. An updated list will be submitted five (5) days prior to the start of the contract and as any personnel or schedule changes are made.

5. Reports

5.1. The contractor shall maintain a daily work log recording the quantities of work performed, the locations, and photo documentation of progress. A copy of this work log shall be filed with the COR on a daily basis.

5.2. The contractor shall note and report to the COR in writing the presence of any conditions that need to be addressed and cannot be corrected within the scope of work described herein. If so directed by the COR the contractor shall provide a proposal for performing the prescribed work that includes a breakdown with unit prices for labor, materials, and equipment required to perform the task(s). The COR will evaluate the proposal and if valid will seek approval from the Contracting Officer. Failure of the contractor to obtain the approval of the Contracting Officer for work beyond the scope of the contract will release the government from any obligation to pay for services claimed.

6. Procedures for Measurement and Payment

6.1. Payment will be included under the quoted line item to which this work relates. Invoices must match these line items.

6.2. All invoices must be verified and approved by the COR prior to payment.

6.3. Invoices accompanied by acceptance reports that have been signed by the COR shall be submitted by the Contractor through the Internet Payment Platform (IPP) System.

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