B08_Attachment_1_-_Revised_Final_Specifications_-_2023_06_09.pdf

INDEPENDENCE NATIONAL HISTORICAL

PARK PHILADELPHIA, PA

PMIS 257208 & 314427

Replace the Wood Shingle Roofs and

Miscellaneous Exterior Repairs 309 - Bishop White House, and 311, 313, 315, 317 Walnut Street

SPECIFICATIONS

June 9, 2023

INDE 257208: 314427 Table of Contents

TABLE OF CONTENTS

DIVISION 01 — GENERAL REQUIREMENTS

Section 01 11 0 Summary of Work Section 01 31 0 Project Meetings………………………… Section 01 32 0 Construction Schedule Section 01 33 2 Submittal Procedures Section 01 35 2 Safety Requirements Section 01 35 9 Historic Preservation Treatment Procedures Section 01 42 0 References Section 01 50 0 Temporary Facilities and Controls Section 01 56 4 Scaffolding ………………………………… Section 01 73 4 Execution………………………………………………………...……..5 Section 01 74 1 Construction Waste Management and Disposal Section 01 77 0 Closeout Procedures

DIVISION 02 — EXISTING CONDITIONS

Section 02 41 1 Selective Structure Demolition Section 02 83 3 Lead Paint Removal and Disposal……………………………….….16

DIVISION 04 — MASONRY

Section 04 10 0 Mortar………………… Section 04 20 0 Masonry Units…………………………………………………..….……. 9

DIVISION 06 — WOOD, PLASTICS AND COMPOSITES

Section 06 01 2 Restoration of Finish Carpentry Section 06 10 0 Rough Carpentry

DIVISION 07 — THERMAL AND MOISTURE PROTECTION

Section 07 20 0 Thermal Insulation……………………………………………...….4 Section 07 31 2 Cedar Shake Roof Section 07 63 1 Sheet Metal Roofing and Flashings Section 07 65 2 Self-Adhering Sheet Flashing Section 07 92 0 Joint Sealants

DIVISION 09 — FINISHES

Section 09 10 0 Plaster Section 09 91 0 Painting Section 09 95 0 Wallcovering ………………………………………………………..3

APPENDICES

Appendix Forms

INDE 257208; 314427 Section 01010

SECTION 01010 SUMMARY OF WORK

PART 1- GENERAL

1.1 SUMMARY:

A. The Contractor shall provide all labor, materials, tools and equipment necessary for the successful prosecution and completion of the work. The project is to be bid as a base bid with two options. The work of INDE 257208 & 314427 – Exterior Repair and Roof Work of 309 (Bishop White House), 311, 313, 315, and 317 Walnut Street shall include, but is not limited, to the following:

1. Remove existing cedar shingle roofing, underlayments and /or felts, and related flashings including counter flashings of the 309 (Bishop White House), 311, 313, 315, and 317 Walnut Street.

2. Where wood shingle roofs are removed inspect existing skip sheathing/shingle lath. Report in writing on the condition of the sheathing/lath to the C.O. Include any lath replacement quantities, if any, in excess of that included in the Basis of Bid. Carry out carpentry repairs as defined in the Basis of Bid. Remove damaged lath that no longer performs as intended and replace with new treated wood replacement lath matching the existing lath in size and shape Minimum length of new lath shall bear on three (3) rafters. Where existing lath that remains after the repair would bear on less than three (3) rafters these short sections of remaining lath shall be included in the replacement. See basis of bid for lath replacement quantities included in the base bid under the contract.

3. Remove the existing sheet metal liners of the built-in pole gutters of the wood shingle roofs in their entirety and inspect wood substrate. Report on condition of the substrate to the C.O. including any quantities of repairs in excess of that included in the basis of bid. Carry out carpentry repairs as defined in the Basis of Bid. New material shall match the existing in size and installation details except that any new replacement wood for the concealed wood of the pole gutters shall be pressure treated to prevent rot.

See Basis of Bid for quantities of work required under the contract.

4. Beginning at the eaves or at the pole gutters where these are found and continuing up the roof slope for a distance of 4’- 0” install new infill between the existing skip sheathing/shingle lath to receive a self-adhering sheet membrane roof underlayment over the solid sheathing thus created along with a nylon three-dimensional matrix shingle breather installed on the underlayment. Existing shingle lath in good condition to remain, the new infill material is in addition to that called out in # 5 below. Existing deteriorated shingle lath shall be replaced as part of # 2 above.

5. Infill between the existing shingle lath as required to accommodate the new shingle weather exposure of the new wood shingle roof. See Basis of Bid for anticipated quantities of supplemental/infill lath to be included in the base bid.

6. Install new zinc or tin coated copper liners in existing pole gutters to match existing installation or as detailed or specified. Ensure proper slope for drainage with no ponding.

7. The contractor shall clean out the existing rain leaders/down spouts to their outlet or their connection to the underground drainage. Where indicated or required repair, rework or replace sections of the existing rain leader/down spouts to eliminate leaks and to correct installation faults. See Basis of Bid for quantities of repair, reworking and replacement. Investigate underground storm water drainage piping connected to the rain leaders/down spouts to determine if drainage is functioning properly.

Testing shall consist of running water with a garden hose at full flow into the underground system for a minimum of 10 minutes to see that the drainage system functions without backing up. Report to CO in writing any deficiencies in drainage. If subsurface drainage is found to be operational tie the existing rain leaders/down spouts into the underground drainage system.

If subsurface drainage is not operational provide temporary corrugated plastic piping runouts to conduct the discharge away from the structure. Up to two (2) sections of 8’-0” plastic piping required at each rain leader/downspout. See basis of bid for required number of runouts in base bid. Repair of subsurface drainage is not in contract.

8. Remove existing chimney down to three courses below cracking or bottom of steel, or to sound masonry beyond three courses, whichever is greater.

Cut back flashing as required when demolition of chimney is undertaken.

Clean end of steel of rust, paint with rust inhibiting paint, install 3-lbs led sheets formed to fully cover embedded steel beam ends to be in masonry.

Inspect structure and stabilize wall for new chimney construction. Report findings to the COR. Reconstruct chimney matching existing brick and mortar finishes. Repair/install flashing at the chimney as chimney is rebuilt.

Install new chimney cap.

9. Inspect the existing standing seam roofing of the rear ell of the 311, and 313 Walnut Street, including associated visible flashing and accessories and report on the condition of the same to the CO in writing including the recommended repairs of any deficiencies. Document the condition with photographs and show deficiencies on marked up plans. No work is required on the metal roofing under the base bid except for the work required to adequately tie in the new flashing of the rebuilt chimney of the rear ell of 313 Walnut Street into the existing metal roofing to create a waterproof installation.

10. Remove the existing chimney caps, where found, from all chimneys of 309 (Bishop White House), 311, 313, 315, and 317 Walnut Street, (see plans).

Fabricate and install new zinc/tin coated copper sheet metal caps including frames, as detailed, on all chimneys, see details Sht. A 14 and Basis of Bid.

11. After removal of the existing sheet metal chimney caps of 309 (Bishop White House), 311, 313, 315, and 317 Walnut Street report on the condition of the underlying masonry in writing to the C.O. Include photos to illustrate typical conditions and any areas requiring repair, including any suggested repairs required in excess of the Basis of Bid repair quantities (see section 01010 1.1E), if any, required to put the masonry in good repair to receive the new chimney caps. Carry out repairs indicated in the basis of bid including the installation of cement washes where they occur. After masonry repairs to the chimneys are completed apply silane masonry damp proofing to exposed top surfaces (horizontal and sloped) of masonry and exposed top surfaces of any cement washes. Install new chimney caps after the masonry is in suitable condition to receive them.

12. At the Bishop White House (309 Walnut St.) remove the existing sheet metal covering of the roof hatch on the rear wing and fabricate and install a new zinc/tin coated copper sheet metal covering matching the details of the removed sheet metal covering.

13. At the roof of the kitchen of 309 Walnut Street (Bishop White House) insert new semi-rigid fiberglass insulation board between the rafters as specified and indicated prior to installing the new wood shingle roof.

14. After roof surfaces intended to receive new roofing are made ready, install new Class B fire treated western red cedar shingle roof with required flashing and accessories as indicated, shown, specified or required to provide a weather tight roofing system. The new flashings shall be zinc or tin coated copper as approved for the new wood shingle roof and be installed as detailed, directed or required. Flashing indicated or required to be laid up in the new wood shingle shall be installed with the wood shingle installation. The contractor’s attention is called to the swept valleys required for the dormer roof valleys on 309 (Bishop White House) to be constructed as detailed in the drawings.

15. At each rain leader/downspout inspect and test for leaks. Report leaks to the COR and perform the Basis of Bid work as indicated.

16. Replace the metal roof coverings of the segmented arch topped dormers of where found. Use continuous cleats at the edges. Allow for expansion and contraction of the metal roof covering. In as far as possible reuse the existing details for installation except as noted herein and as modified for movement.

17. Inspect the exterior brick and stone masonry surfaces of 309 (Bishop White House), 311, 313, 315, and 317 Walnut Street for damage, cracking, spalling or delamination and other failure. Report in writing to the CO on the condition illustrating typical and severe conditions with photographs along with recommendations for repair and repair quantities in excess of the Basis of Bid quantities. Carry out masonry repairs as indicated up to the quantities called for in the Basis of Bid under section 1.1E. Consult with the OR to determine the order of repair priorities. New mortar shall match the color and joint profile of the existing mortar as approved by the COR. Up to 3 mortar colors may be required.

18. After removal of the existing sheet metal parapet flashing and/or coping and the parapet masonry is exposed on 309 (Bishop White House), 311, 313, 315, and 317 Walnut Street report on the condition of the underlying masonry in writing to the C.O. including any suggested repairs required in excess of the Basis of Bid repair quantities, if any, required to put the masonry in good repair to receive the new zinc/tin coated copper parapet flashing and/or coping. Install the new parapet flashing and/or coping after masonry repairs are complete in conjunction with the new wood shingle roof.

19. Inspect existing roof trim - verge or rake boards, soffits, fascia, and cornices and the woodwork of the dormers of 309 (Bishop White House), 311, 313, 315, and 317 Walnut Street. Report on the condition of the roof trim - verge or rake boards, soffits, fascia, and cornices and the woodwork of the dormers in writing to the C.O. Document the conditions with photographs and show deficiencies on marked up plans. Particular attention should be paid to areas of damage that interferes with the installation of a weathertight roof or would be difficult to repair once the new roof is in place. Include quantities of repair, if any, in excess of that included in the Basis of Bid.

Carry out carpentry repairs as defined in the Basis of Bid after consulting with the COR on priorities for replacement. Replace existing deteriorated material including blocking necessary to securely attach the new finish material. The new material shall match the size, shape, profile, species and grain orientation of the material being replaced unless otherwise indicated or directed. See basis of bid for quantities of work required under the contract. Do not perform work in excess of that called for in the drawings and the Basis of Bid without written instructions from the CO.

20. At the pedimented entrances at 309 and 315/317 Walnut Street, doors 101 & 102, clean, prep, and paint these doors and all their surrounding woodwork. Prior to painting report on any required repairs beyond normal painting prep work of sanding, scraping, filling and caulking. No repairs required under base bid. Note that work requires lead paint remediation.

21. At door 103 at the rear entrance to courtyard from 309 Walnut Street, Cut approximately 1” from the bottom of the tongue and groove exterior boards to remove deteriorated ends of the boards. Prime paint cut ends and install a new treated wood horizontal filler piece to replace the removed ends. Install a new bevel cut rain shield as shown. Prime and paint the rain shield before installation. Prep and paint the exterior face of Door 103 and frame. Color to match the existing color. Note that work requires lead paint remediation.

22. Inspect existing dormer windows including frames and sills of 309 (Bishop White House), 311, 313, 315, and 317 Walnut Street. Report on the condition of the dormer windows including frames and sills in writing to the C.O. including any quantities, if any, in excess of that included in the Basis of Bid that are required to put the above exterior woodwork of the dormers in good repair. Document the conditions with photographs and show deficiencies on marked up elevations of the buildings. Perform repair work called out in the drawings and in the Basis of Bid See basis of bid for quantities of work required under the contract. Do not perform work in excess of that called for in the drawings and the Basis of Bid without written instructions from the CO.

23. Provide all labor and materials to reconstruct the shed porch at the entry to the lower-level basement entry at the back of the rear ell of the Bishop White House, 309 Walnut Street, as detailed and shown in the drawings.

The shed porch to be constructed with Honduras Mahogany (Swietenia macrophylla), flat cut or as approved by the Contracting Officer or their designated representative with a new wood Cedar shingle roof.

24. After exterior woodwork repairs and construction are complete perform all required or specified painting prep work at of 309 (Bishop White House), 311, 313, 315, and 317 Walnut Street. Prime paint the exterior woodwork of the cornices, rakes, dormers and any other areas or features where wood repairs or construction were carried out. Include the exterior woodwork pedimented doorways on 309 & 315 Walnut Street and exterior of the door to rear courtyard from 309 Walnut Street. Include back priming of new wood and prime painting of those portions of the existing wood material exposed during the work. After all priming is completed paint all exterior woodwork receiving prime paint or called out for painting as specified.

Each feature or architectural element is to be prepped and painted in its entirety according to specifications with no partial or spot painting allowed.

Colors to match the existing paint colors of the features being painted. Note that shutters are not included in the exterior woodwork or painting. Note that work requires lead paint remediation.

25. As indicated in the drawings on sheets A7 and A8 at locations on the 1st, 2nd, and 3rd floors in 309 Walnut Street (the Bishop White House) for plaster repair, remove the damaged, failed wallpapers as directed or required. The existing wallpaper is to be carefully cut at the first joint(s) beyond the damaged plaster and damaged wallpapers removed. If wallpaper borders removed are in suitable condition for reuse with minor cleaning, salvage and clean the borders and make it ready for reuse. Cover the wallpaper to remain as directed to protected it from dust, or damage, maintain protection throughout the plaster repairs. At the conclusion of the plaster repairs and after the new plaster has sufficiently cured reinstall new owner supplied wallpaper and reused borders if approved for reuse. See Basis of Bid for expected quantities of wallpaper repairs.

26. At locations indicated in 309 Walnut Street (the Bishop White House) for plaster repair remove the damaged, failed finish plaster, scratch and brown coats as directed or required. Include dust protection, including negative air, to prevent dust and debris from the plaster repairs contaminating areas within the house beyond the immediate plaster repair work areas. Maintain the protection throughout the plaster repairs. Clean any existing wood lath and make it ready to receive new plaster. Install new metal lath as specified.

Where required, due to damage or rot, cut out the existing wood or metal lath and install new metal lath as specified to replace or supplement the existing lath. If the scratch and/or the brown coats appears sound and undamaged they may remain and be reused if accepted by the COR. After removal of the damaged or failed plaster is complete and the lath or existing scratch or brown coats are made ready, apply a new lime-based plaster system matching the existing plaster installation in number of coats. Follow Section 09100 Lath and Plaster of these specifications for the mix and materials of each coat required. New flat plaster patches shall be brought to the level of the surrounding sound plaster to form a uniform, smooth surface. Molded plaster surfaces shall match exactly the profile of the existing molded plaster remaining in size and shape and shall be brought to the level of the remaining sound plaster molding to which it joins to form a uniform, smooth surface with no visible joint. At locations where damaged molded plaster is removed the plasterer shall make new sheet metal molding profiles to accurately reproduce the existing molded plaster and recreate the same to fill in the missing sections. Where the existing wall was painted, after the plaster is properly cured, prep and paint the entire wall or surface in which the patch occurs painting to the natural borders or stopping points to give a uniform appearance. Colors shall match the existing color of the repaired surface. Refer to number 24 above for wallpaper finishes.

See Basis of Bid for expected quantities of plaster repair, do not perform any repairs in excess of the Basis of Bid quantities without written authorization of the CO.

27. Install scaffolding including all accessories as specified or required to provide access to the exterior and interior work areas. Provide pedestrian bridges at all building exterior doors as delineated on the Drawings and along the entire Walnut Street elevation of the project area. Entries and the

Walnut Steer sidewalk must remain open for the duration of the work.

Secure any required permits or permissions for the erection of the scaffolding along the Walnut Street. elevation. Contractor may use lifts to the rear and sides of the buildings where sufficient clearance exists, protect existing ground and paving surfaces from damage. Follow all OSHA requirements for scaffolding and lifts.

28. Provide protection for the existing buildings and building systems during the work of this contract. Protections include but are not limited to interior dust protection including negative air to limit plaster dust to the immediate area of the work, covers on HVAC vents, floor protection, and covers or protection of door jambs, window jambs, stair treads and railings, and other protective coverings of historic finishes and woodwork as may be required to ensure the protection of the resource. Provide protection from the weather during re-roofing operations.

29. Protect the existing plantings, plants, trees, and landscape features including paving during the work of this contract.

30. Option # 1: Bishop White rear yard perimeter wall work description.

Perform work only if Option #1 is accepted and authorized. Do not exceed the quantities of work as outlined below without written authorization from the

CO.

a. Masonry:

1. Remove indicated or deteriorated mortar joints to a depth of ¾” and repoint with specified mortar matching the joint profile of the surrounding sound masonry or as approved by the COR. Mortar shall match the color and joint profile of the existing mortar as approved by the COR.

Include 50 SF of spot repointing of the wall face.

2. After the shingles of the wall cap are removed and deteriorated portions of the wall cap framing are removed clean top of masonry wall of any loose debris and remove any failed mortar wall coping and/or failed masonry joints.

To the extent possible include areas where the wall cap framing remains. Cut back failed mortar joints to a depth of ¾” and repoint with specified mortar bringing the new joint flush with the bricks at the top of the wall.

Include 20 SF of spot repointing of the top of the wall.

b. Carpentry:

1. After the removal of the cap shingles consult with the COR to determine the extent of the removal required of the wall cap framing. Remove deteriorated wall cap framing as directed up to the quantities listed below.

Provide and install the quantities of work listed.

a. Provide and install up to 75 LF of new 1x4 treated wood shingle lath.

b. Provide and install five treated wood gable framing elements or assemblies as shown or as found in the original framing of the wall cap .

c. Provide and install up to 24 LF of new treated wood sleepers. The repairs may be distributed along the length of the wall in up to six sections 4’-0” long.

d. Include and install up to 30’-0” of new galvanized metal lath where lath is damaged or has been removed, include any required demolition needed for the installation.

e. Provide and install up to 12’-0” of beaded fascia board matching the existing fascia board in size, shape, and profile. Include demolition of the existing deteriorated fascia. New fascia to be Honduras Mahogany or other rot resistant wood as approved by the COR. Replacement repairs may be in up to four locations with minimum length of 3’-0”. New splice joints shall be scarf joints.

f. Carry out epoxy repairs to the wood lintel of the gate way of the backyard perimeter wall. Repairs to consist of the removal and/or the consolidation of the “punky wood” allowed to remain and rebuilding the lintel to its original size, form, and shape with epoxy filler. All work to follow epoxy manufacturer’s recommendations and instructions.

d. Roofing:

1. Remove the existing wood shingle wall cap shingles in their entirety including all felts, nails and flashing to prepare the existing shingle lath to receive the new wood shingle wall cap. The existing expanded metal lath may remain where it and the lath and framing under it is undamaged. Carry out the carpentry repairs above to make framing ready to receive the new shingles.

2. Install new fire treated wood shingle wall cap as detailed and specified including all flashing and accessories. Match the existing installation for weather exposure, length, and thickness of the shingles. Shingles are to be cut to size from specified 24“shingles.

e. Painting:

1. Clean and prep the existing facia boards on both sides of the wall below the shingle wall cap for painting.

2. Prime the facia boards as specified including back and end grain priming of new replacement wood, and paint with 2 coats of specified finish paint. Match the existing color as approved by COR.

31. Option # 2: 319 & 321 Walnut Street. The contractor shall provide a cost for the inclusion of the re-roofing and repair of the exterior of 319 & 321 Walnut Street as indicated on drawing sheets A -17 & A -

18. Where the type of work required is covered under the Basis of Bid the quantities required for that work are to count against the Basis of Bid quantities. The Contractor is reminded not to exceed the quantities of work set forth in the Basis of Bid without written authorization from the Contracting Officer. All other aspects of the specifications and drawings will apply to the work on 319 & 321 Walnut Street if Option # 2 is accepted.

B. The primary goal of the project is to minimize future repairs and preserve the historic fabric of 309 (Bishop White House), 311, 313, 315, and 317 Walnut Street by replacing the wood shingle roofs and carrying out specified repairs to the exterior envelope of the houses. The work requires but is not limited to carrying out limited repairs as indicated to the exterior woodwork, lead paint remediation, painting at the location of repairs and painting of the cornices, rakes, dormers and other woodwork associated with the roof work, limited repointing the exterior masonry of the houses and replacing the existing wood shingle roofing systems of the houses. Additional work includes repairing interior plaster of the Bishop White House, demolition and rebuilding damaged hung gutters on the rear wing of The contractor should note any needed repairs not called out or indicated for repair in the plans and specs and report the same to the COR. Do not perform any repairs not called out or indicated as part of the work without written authorization from the CO.

C. All work will be performed under a single contract.

D. The contractor shall submit phasing schedule as appropriate to maintain access to the buildings for review and approval by Contracting Officer prior to a Notice to Proceed.

E. Basis of Bid:

The Contractor shall include the following Basis of Bid quantities of the indicated work in their base bid to cover the cost of this work. These Basis of Bid items are intended to aid the contractor in determining the quantities required for work that may be concealed or may be subjective in nature and should not be viewed as identifying all work required to complete the work. The contractor should carefully review the construction documents (plans and specifications) in addition to reviewing the Basis of Bid items in developing his bid. Verify quantities of items of work in both the specifications and plans. Should work covered in the Basis of Bid categories exceed the quantities listed the contractor shall notify the CO and the COR in writing as soon as such discrepancies become apparent and await directions before beginning the portion of the work that will exceed the stipulated quantities.

1. After the removal of the existing wood shingle roof remove the existing roof sheathing or shingle lath where the existing roof sheathing or shingle lath is rotted or unsound or otherwise unfit to receive the new roof. Replace with new board sheathing or shingle lath sized to match the existing installation and the approximate the width of the existing wood boards or shingle lath.

Match the new material to the approximate thickness of the existing [assumed thickness ¾”] with minimal shimming. Sheathing boards over 11”in width may be replaced with multiple boards to match the original width. In such cases the contractor shall use the minimum number of boards required to match the width. Minimum board or lath removal/replacement is the span of three rafters or supports (approximately 48”). This work is in addition to the infill between the existing shingle laths to accommodate the new shingle weather exposure and at the eave or pole gutters to 4’ up the roof slope identified under Carpentry.

Basis of Bid lath replacement quantity – 150 L.F.

2. After the removal of the existing wood shingle roof measure the spacing of the existing shingle lath to determine if the specified shingles can be properly installed with the specified weather exposure. If required provide and install infill lath between the existing shingle lath, cutting as required to fit the new infill lath for optimal spacing to receive the specified shingles. New infill lath will be nominal dimensioned treated lumber. Match the new material to the approximate thickness of the existing [assumed thickness ¾”] with minimal shimming. Provide a unit price for modifying the contract price for substantial differences in the actual quantities required. A substantial difference is defined as 5% more or less than the Basis of Bid Quantity provided below.

Basis of Bid for new infill lath – 5,500 LF

3. Inspect the entire cornice assembly, rake boards and trim associated with the roof including the dormers. Replace two modillions and associated trim.

Perform minor repairs by patching and filling holes, filling splits, re-securing loose sections or pieces and paint with two coats of exterior semi-gloss paint matching the existing color. Replace deteriorated, damaged or rotten sections of the existing molded wood cornice with new wood cornice and trim pieces matching the existing wood cornices, rakes and trim including that of the dormers in size, shape and olding profile. New Material shall be Honduras Mahogany or approved equal. Construction of assemblies shall match the existing in terms of built-up sections/assemblies or pieces, no glued-up sections or pieces will be allowed as replacements for solid wood sections or pieces. Include one coat of prime paint on all surfaces of the replacement pieces and two coats of exterior semi-gloss paint on exposed paint surfaces.

The second coat may be the part of the cornice/trim painting required under the contract. Match the exterior color to the existing color of similar or surrounding painted wood surfaces.

Basis of Bid for cornice repair quantity –

a. 15 L.F. of ea. shape, type, or piece of trim.

b. Provide and install two modillions and associated trim.

c. Provide and install new windowsills at two dormer windows. Match existing sill size, shape and profile.

4. In locations requiring the replacement of roof sheathing or shingle lath inspect rafters for rot, failure or other damage. At the existing rafters showing signs of rot, failure or damage sufficient to inhibit the securing of shingle lath to the rafter, scab a new 2x6 to one side of the damaged rafter.

Trim scab to fit the depth of the rafter if required. Extend the scab a minimum of 1’-6” beyond the area of damage in each direction. Stagger nail scabs @ 6” o.c. with 8d nails. Remove additional shingle lath as required to enable the repairs. Additional shingle lath removal and replacement are to be applied to the shingle lath replacement quantity above.

Basis of Bid quantity – 1 rafter w/assumed repair length at 5’-0” including the lapping at either end of the repaired area.

5. Repair existing dormer windows and indicated doors of 309, 311, 313, 315, and 317 Walnut Street as described in the Window and Door Schedules found in the drawings. In addition to those repairs include 2 windowsill replacements and one door sill replacement to be used at the direction of the

COR.

6. Other wood/carpentry repairs:

Basis of Bid quantities:

a. Cut out and remove rotted boards at bottom of door D-103 and install new horizontal treated wood filler with wood coping water shield as shown.

b. Remove and replace up to 10 LF total of rotted or damaged vertical leg of pole gutters in multiples of 30” or less at up to 4 locations. New material to be treated wood of nominal dimensions built up and/or cut down to match existing. Reuse existing ell brackets where possible, supplement with up to six (6) new brackets as needed sized as closely as possible to the existing.

c. In lieu of the existing shingle siding of the dormers and the bulkheaded parapet dormer of 309 Walnut Street (Bishop White House) provide and install new beaded board ship lapped siding as shown and detailed in the drawings.

d. Replace the existing shingle siding of the dormers at 311-313 and 315-317 Walnut Street with new Class B fire treated western red cedar shingles, matching new material for roofs.

e. Reconstruct the rear shed roof structure at the rear courtyard of 309 Walnut Street (Bishop White House) as detailed or required.

7. Repair/spot repoint the masonry of all parapet walls and chimneys of 309, (Bishop White House), 311, 313, 315, and 317 Walnut Street above the roof from the roofing substrate to the top of each parapet wall or chimney to make the masonry ready to receive the new work to be attached to it and/or to put it in good repair. At 309 (Bishop White House repoint the east wall as indicated in the drawings including the removal of the existing mortar as required to accomplish the work. Spot point the brick and stone masonry of 309, 311, 313, 315, and 317 where and as determined in consultation with the COR up to the quantities set forth below.

Basis of bid quantities –

a. 750 SF of spot repointing with a matching joint profile and mortar color as specified or selected. Include raking or cutting out of mortar joints to min. depth ¾”.

b. Remove, clean and reset 25 loose or unbonded bricks. Use a joint profile and mortar matching surrounding or adjacent masonry.

c. Provide and set up to 50 new bricks matching the existing brick in size, shape, color and texture. Include demolition as necessary to prepare the surrounding masonry to receive the new bricks. Up to two (2) distinct sizes and colors of brick may be required. The new bricks will be used as replacements for damaged or missing brick as identified by the COR.

The joint profile and mortar color shall match the surrounding or adjacent masonry. Turn over any remaining brick not used in the masonry repairs to NPS.

d. Inspect the existing parapets once the existing roofing system is removed to determine the parapet’s masonry suitability to receive the new roofing system. Note any deficiencies and report in writing to the CO and COR any deficiencies that cannot be repaired using the Basis of Bid quantities for the repointing and setting of new or loose unbonded brick. Provide photographs of conditions in question and provide quantity estimates of additional work beyond the Basis of Bid quantities.

1. Rake or cut out the exposed joints on the top (horizontal and/or sloped) surfaces of all exposed parapets or parapets exposed during the re-roofing/flashing work to a min. depth of ¾” and repoint with a matching joint profile and mortar as specified.

e. Rake out or clean all existing reglets to make ready to receive new flashing.

f. Rake or cut out the exposed joints on the top (horizontal and or sloped) surfaces of all chimneys to a min. depth of ¾” and repoint with a matching joint profile and mortar as specified. Where mortar or cement washes are found remove failed, cracked or unbonded washes or portion of washes and re-point the exposed masonry beneath the removed wash. Recess the new joints ¼” below the surface of the brick surface to provide keying for the new cement wash and replace with new cement washes matching the slope and dimensions (depth and width) of the replaced wash or portion thereof. Blend new wash to the existing wash where portions of the existing wash is incorporated with the new.

g. Where the existing chimney caps are removed clean out any failing mortar joints and repoint the same before installing new caps.

8. Provide the following quantities of interior plaster demolition and repair/replacement for the Bishop White House. Dust containment and surface protection is required. Cutting back and removal of damaged existing wallpaper where found at the locations of required plaster repairs is also included in the demolition of the underlying plaster. The wallpapers shall be cut or removed at the first seam beyond the area of plaster damage.

Basis of bid quantities –

a. Full plaster removal and replacement: 575 SF new 2 or 3 coat lime-based plaster.

Match the finish of the remaining sound plaster.

b. Removal of up to 200 SF of existing metal lath and replacement with up to 280 SF of new galvanized expanded metal lath with min. 6” lap over remaining existing lath.

c. Removal of up to 25 SF of existing wood lath and replacement with 35 SF of new galvanized expanded metal lath with min. 6” lap over remaining existing lath.

d. The removal of up to 875 SF of failing skim coat plaster finish and the repair of original finished plaster thus exposed.

Include the feathering of the edges of the surrounding undamaged, well bonded skim coat to the newly exposed and repaired finish plaster using the specified finish plaster white coat.

e. The removal of up to 325 SF of failing skim coat plaster finish to the surrounding undamaged, well bonded skim coat and the installation of a new finish plaster skim coat using the specified finish plaster white coat. Bring the new skim coat to the level of the remaining sound skim coat plaster finishes creating a smooth, even, undetectable transition between the old and the new.

f. Remove up to 8 L.F. of run molded plaster cornice, total divided between two locations. Each location will require its own distinct molding profile. Cut back to sound plaster and replace with new matching run molded plaster cornice matching the existing molding in size, shape and profile. Bring the new plaster molding to the level of the remaining sound molded plaster finishes creating a smooth, even, undetectable transition between the old and the new moldings.

9. After the repaired plaster has cured to create a suitable substrate for the installation of wallpaper the contractor shall have a qualified company regularly engaged in and skilled in installation of wallpaper to reattach any loose undamaged wallpaper and to hang new wallpaper to replace any missing, damaged or destroyed wallpapers. Do not reattach any papers that are torn, stained or otherwise damaged. The owner will supply new wallpaper in sufficient quantities to replace missing, damaged, or destroyed wallpapers. Where new wallpaper is required the rolls of wallpaper supplied by the owner will be cut into short sections or panels of approximately 19” in length and attached to the wall with paste to form a historically accurate installation. Horizontal lap joints between pieces of wallpaper shall be approximately ¼” to 3/8”, carefully match the decorative pattern between paper panels. Where new paper joins existing papers carefully maintain existing layout of panels by joining the new paper to the old at existing seams. Remove any partial panels prior to starting installation. Match the decorative patterns in new panels to the old.

Basis of Bid quantities:

a. For cleaning and reattaching loose undamaged wallpaper – 20 SF

b. For owner supplied new wallpaper installation – 400 SF

10. At existing rain leaders/downspouts conduct a water flow test by inserting a min. ½” diameter garden hose connected to the owner’s water supply into the inlet and running the hose at full flow for 5 minutes. Look for leakage in the rain leaders/down spouts and notify the COR of any observed. Clean any blocked rain leaders/downspouts to the extent possible by rodding them out.

Basis of Bid quantities:

a. At the COR’s direction repair or replace up to three (3) 36”sections of the existing rain leaders/downspouts as detailed in the drawings.

Test the underground drainage at each rain leader/downspout discharge with a water flow test by inserting aa min. ½” diameter garden hose connected to the owner’s water supply into the inlet and running the hose at full flow for 10 minutes. Report any back ups or blocked pipes to the COR. Repair or unblocking of the underground drainage is not in the contract.

1.2 DURATION OF THE CONTRACT

A. All work shall be completed within ninety (90) days from the Notice to Proceed, given normal weather conditions. Fair and reasonable extensions may be granted for unforeseen circumstances at the discretion of the Contracting Officer.

1.3 LOCATION: The location of the project is at 309, 311, 313, 315, and 317 Walnut Street, Philadelphia PA 19106

1.4 CONTRACTOR'S USE OF PREMISES:

A. The site will remain open to NPS personnel and the public during construction.

Contractor will maintain access to the main and the rear building entrances as shown on the drawings throughout the construction phase to permit staff and visitor access. If closure of the building entry is required, then Contractor shall notify Contracting Officer no less than 72 hours prior to entry closure. No building entry shall be closed without prior approval by Contracting Officer.

1. The Contractor’s construction activities shall not interfere with building access for employee use throughout the construction phase. The NPS reserves the right to reschedule work that causes excess fumes or noise which interrupts normal work.

2. The Contractor will protect pedestrians from falling overhead debris, with debris netting installed on scaffolding, yellow warning caution tape, and guardrails. A minimum of two rolls of warning tape will be kept on site at all times.

3. The National Park Service (NPS) will not tolerate any deviation from the specifications noted for the safety of the park's staff or visitors at all times.

4. The Contractor shall erect scaffolding bridges to maintain unobstructed egress from the building doorways for the duration of overhead construction.

The Contractor shall provide and maintain barricades between work areas and egress routes.

5. The contractor shall install overhead protection in the form of a pedestrian bridge along the north sidewalks. All sidewalks around the building shall remain open to the public throughout the entirety of the project.

B. The Contractor shall notify the Contracting Officer of the proposed work schedule, i.e., typical workday, prior to mobilization on site. This is to aid NPS Protection staff in monitoring the site. The Contractor shall notify the Contracting Officer whenever work will take place on the site, so that the work can be monitored and to allow for coordination with Park operations.

1. The Contractor shall at all times conduct his operations to ensure the least inconvenience to the occupants and disruption to visiting public.

a. No loud radios or other forms of music shall be permitted.

b. Loud noise shall be kept to a minimum.

c. No loud, inappropriate language toward or around any Park staff, visitors or other members of the public.

C. Use of Site: Limit use of premises to areas within the Contract limits indicated. Do not disturb portions of Project site beyond areas in which the Work is indicated.

1. Limits: Confine construction operations to areas indicated on the Drawings.

D. Nonsmoking Building: Smoking is not permitted on NPS Property at any time.

E. Materials shall be taken up the scaffolding by hoist attached to the scaffold or by high lift as permitted by the lift manufacturer’s and OSHA’s safety requirements.

F. Work and storage of materials shall take place in the work area prescribed by the

Contracting Officer and in accordance with NFPA 241 Standard for Safeguarding Construction, Alteration, and Demolition Operations.

1.5 WORK RESTRICTIONS

A. Delivery of material:

1. Vehicular Restrictions: It is important that the historic scene in the Park be preserved for the enjoyment of the Park’s visitors for this reason there is no on site parking permitted. Limited vehicular access may be permitted for the loading and unloading of Contractor vehicles with the permission of the COR. For a possible street parking permit, which allows free parking at legal metered spaces, contact Philadelphia Parking Authority. Permit is good for 6 months.

B. The Contractor will be permitted to work Monday through Friday between 7:00 a.m.

and 5:00 p.m. Work performed at any other time or on Federal Holidays may be done only with prior approval of the Contracting Officer and the Park.

1. Contractor shall request permission from the Contracting Officer one week in advance to work on Federal Holidays, weekends or outside of the normal 7:00 a.m. to 5:00 p.m. schedule.

2. The Contracting Officer may, with at least 2 weeks written notice, designate “no work days” due to special events at the site.

1.6 SPECIAL CONSTRUCTION REQUIREMENTS:

A. Historic Status and Review Notice:

1. The Bishop White House and 315, 317 Walnut St. are on the List of Classified Structures. Independence National Historical Park is on the National Register of Historic Places. 311 and 313 Walnut St. are not on the list of certified structures, but the Park has chosen to treat them as historic structures. The Contractor is advised of the following:

a. The work to be performed on these buildings will meet the highest standards of preservation and building craftsmanship.

b. The Contractor will be intimately familiar with the Secretary of the

Interior Standards for the Treatment of Historic Properties, specifically standards for restoration and rehabilitation.

c. Proper attention shall be given during construction to ensure that there is no loss of significant or historic fabric during construction activities.

d. Maintain existing building in a weather-tight condition throughout construction period. Repair damage caused by construction operations. Protect building and its occupants during construction period.

B. Preservation of Natural Features: Confine all operations to work limits of the project. Prevent damage to natural surroundings. Restore damaged areas, repairing or replacing damaged trees and plants, at no additional expense to the NPS.

1. Provide temporary barriers to protect existing trees and plants and root zones.

2. Do not remove, injure, or destroy trees or other plants without prior approval. Consult with the Contracting Officer and remove agreed-on roots and branches that interfere with construction (only after written approval).

3. Do not fasten ropes, cables, or guys to trees.

C. Prior to start of work, the Contractor shall examine work site with Contracting

Officer or designated representative to determine exact limits of work and the conditions under which this work will be performed.

D. All vehicles including high lifts, operating on paved areas shall comply with the following requirements:

1. All vehicles are required to use pneumatic tires.

2. The Contractor will be held responsible for the protection of the brick sidewalks and will be held accountable for any damage that occurs as a direct result of the work. Any vehicles that exceed a gross weight of 10,000 pounds must use the protection described below. Using this method does not relieve the Contractor of responsibility to protect the walkways from damage.

a. Two layers of ¾” plywood, with a layer of 2” Styrofoam paneling in between, laid in such a manner that the surface of the paved area is covered to all extents of its surface.

b. When the Styrofoam has compressed to a height that is less than half its original thickness, or to an extent that the Styrofoam is not protecting the paving, it is to be replaced as described above.

3. Post signage to route pedestrians around construction as recommended by the Contracting Officer.

4. Protect pedestrian traffic by guardrails.

5. Cover pipes, hoses, and power lines crossing sidewalks and walkways with troughs using beveled edge boards.

6. Removal: Completely remove barriers no longer needed and when approved by Contracting Officer.

E. Temporary Controls:

1. Housekeeping:

a. Keep project work site neat, orderly, and in a safe condition at all times.

b. Provide enough refuse containers for collecting construction debris and have them removed from the site or emptied daily.

c. Wet down dry materials and rubbish to prevent blowing dust.

d. Keep volatile wastes in covered containers.

2. Proposed dumpster and/or refuse container location shall be submitted to Contractor Officer for review and approval prior to dumpster/refuse containers being brought to the site.

F. Air and Water Pollution Control:

1. Take all necessary reasonable measures to reduce air and water pollution by any material or equipment used during construction.

2. Do not dispose of volatile wastes or oils in storm or sanitary drains.

G. Provide constant protection against rain, wind, storms, frost, and heat so as to keep work and materials free from damage. At the end of each day's work, cover work likely to be damaged. During cold weather, protect work from damage by freezing.

1.7 FIELD VERIFICATION: Field verify all new and existing dimensions affecting the work of this contract before fabricating work.

1.8 QUALITY CONTROL:

A. The Contractor’s designated quality control supervisor shall be employed full time at the project site whenever contract work is in progress.

B. Methods of monitoring and controlling environmental pollution and contamination shall be used as required by regulations and laws.

C. The Contractor shall submit worker qualifications documenting the required experience for the following firms and/or personnel:

1. Job Site Superintendent: Minimum of five (5) years as Job Site Superintendent managing jobs of similar size and complexity. List minimum of one (1) job managed that required the following of the Secretary of the Interior’s Standards for the Treatment of Historic Properties; Rehabilitation Guidelines.

NOTE: Projects involving the Secretary of the Interior’s Standards typically include federal government construction work on buildings listed or eligible for listing on The National Register of Historic Places or private commercial properties being rehabilitated for the Federal Tax Credits for Historic Rehabilitations but may include other projects where the owner elects to follow the Secretary of the Interior’s Standards. For a copy of the Secretary of the Interior’s Standards for Rehabilitation see:

https://www.nps.gov/tps/standards/rehabilitation.htm

2. Lead Restoration/Finish Carpenter: Minimum of five (5) years as a Restoration/Finish Carpenter performing repairs on historic properties requiring the matching of period details and repairs in historic woodwork. List a minimum three (3) projects involving one or both of the required work.

3. Masonry repair and restoration requirements:

a. Contractor performing the masonry work shall have a minimum of 5 years of experience in…