Fort Wilkins - Chimney repairs scope of work - Addendum #1.docx

2018 – Fort Wilkins Historic State Park – Chimney and Bakery Oven Repairs - Scope of Work– Revised for Addendum #1 – 8-17-18 (Revisions highlighted) I. Statement of Work: Complete all work identified in the plans, specifications, and scope of work, including performing brick masonry repairs and brick replacement on all chimneys within the historic fort complex on the identified structures. Additionally, re-build the bakery oven. This report includes work on chimneys at the following structures:

A. Chimneys

i. West officer’s quarters

ii. Central Officer’s quarters / triplex

iii. East officer’s quarters B. Bakery oven & chimney

II. A note regarding lead paint: All chimneys and bakery oven – Unless tested, it should be assumed that all of the chimneys contain lead base paint. Proper work practices and safety precautions are required. Respirators should be worn during cutting operations for personnel safety. HEPA vacuums should be used to contain dust during cutting operations. A lead based paint assessment was performed and the results and report are attached for the contractor’s reference.

III. Chimneys: Perform brick masonry repairs to all chimneys listed below. Brick masonry repairs to the chimneys apply from the top of the chimney to just above the roof line. Brick masonry repairs are intended to remove, replace, rework, or modify the roof flashings tying into the chimneys. The contractor is to remove and re-point mortar joints that include chimney flashing embedded within the mortar joints if found to be in loose, damaged, or deteriorated condition. Work is to apply only at or above the roof deck and is not intended to require removal of the existing roofing system. All chimney flashings are required to be reworked according to industry best practices and provide a durable water tight seal.

A. Repointing of all masonry joints to apply at the following locations:

i. West officer’s quarters (4 chimneys)

ii. Central officer’s quarters (6 chimneys)

iii. East officer’s quarters (4 chimneys) B. Brick replacements are proposed to occur at the following locations:

i. West officer’s quarters

1. NW Chimney - replace 20 bricks

2. NE Chimney – replace 15 bricks

3. SW Chimney – replace 35 bricks

4. SE Chimney – replace 20 bricks

ii. Central officer’s quarters

1. NW Chimney - replace 60 bricks

2. NE Chimney – replace 50 bricks

3. SW Chimney – replace 25 bricks

4. SE Chimney – replace 5 bricks

5. Central north chimney – replace 75 bricks

6. Central south chimney – replace 5 bricks

iii. East officer’s quarters

1. NW Chimney - replace 30 bricks

2. NE Chimney – replace 60 bricks

3. SW Chimney – replace 25 bricks

4. SE Chimney – replace 5 bricks C. Mortar specifications:

i. Type N mortar.

D. Brick masonry joint specifications:

i. Joint type: Concave joint

ii. Head joint width: Match existing joint widths

iii. Bed joint width: Match existing joint widths

iv. Bed and head joint depth: Remove old mortar to a depth of 2 to 2 ½ times the width of the joint to ensure an adequate bond.

E. Brick masonry specifications:

i. Standard requirements: Brick masonry units must comply with ASTM C 216 – 17a Standard Specifications for Facing Brick

ii. Brick type: FBS

iii. Brick grade: SW

iv. Brick color: Red

v. Brick edge: Tumbled

vi. Brick dimensions:

1. Width: Approximately 3 ½”

2. Height: Approximately 2 – 1/4”

3. Length: Approximately 7 - 7/8”

vii. Intent: The intent is to match the brick dimensions and brick colorations of the bricks used on the guardhouse and blacksmith shop chimneys or of the bricks found on the east, west, or central officer quarter’s chimneys.

F. Chimney alignment, and style requirements: Chimneys should be constructed to replicate existing alignments, dimensions, and styles (layering of courses) G. Cleaning of work requirements: Clean the newly re-pointed masonry. Use plain water and a stiff natural bristle or nylon brush to remove masonry residues adjacent to joints and on brick masonry. Use a wooden paddle or chisel to remove mortar that has hardened. Mortar shall be fully hardened before cleaning occurs.

H. Painting: All brick masonry work performed is not required to receive a paint treatment after the work is performed. This work will be performed by others.

IV. Bakery oven: Re-construct the brick bakery oven. Limits of reconstruction includes reconstructing the brick masonry courses from the lowest elevation which brick masonry occurs (beginning at the stone masonry / brick masonry mortar joint) and continuing up in elevation to the top of the chimney.

A. Items of work:

i. Reconstruct brick masonry layers which are found to be deteriorated. Remove loose, deteriorated, and damaged layer until sound mortar and brick masonry is encountered. Reconstruction may apply to multiple layers brick layers (estimated to include the 2 most exterior courses only).

1. Brick replacements

a. Approximately 160 bricks required to be replaced on north side.

b. Approximately 160 bricks required to be replaced on the east side.

c. Approximately 75 bricks required to be replaced on the south side.

d. Approximately 125 bricks required to be replaced on the top of the bakery oven.

e. Approximately 25 bricks required to be replaced on the chimney of the bakery oven.

2. Brick masonry repairs are repointing is required to occur across the entire top surface and to a maximum depth of 2 brick courses should loose, damaged, or deteriorated masonry be found.

3. Cleaning of work requirements: Clean the newly re-pointed masonry. Use plain water and a stiff natural bristle or nylon brush to remove masonry residues adjacent to joints and on brick masonry. Use a wooden paddle or chisel to remove mortar that has hardened. Mortar shall be fully hardened before cleaning occurs.

ii. Brick masonry repairs are to apply to the exterior of the bakery building only. No brick masonry repairs are requested on the inside of the building or on the inside of the bakery oven. Exterior brick masonry repairs are to apply to the north, east, south, and top elevations of the bakery oven and its chimney (also includes west face).

iii. Stone masonry repairs. Excluded from the scope of work is the repointing of loose, damaged, and deteriorated masonry of the stone masonry foundation. Please refer to the plan set titled “A-108-a bake oven details.pdf” to identify limits of stone masonry.

B. Mortar specifications:

i. Type N mortar.

C. Brick masonry joint specifications:

ii. Joint type: Concave joint

iii. Head joint width: Match existing joint widths

iv. Bed joint width: Match existing joint widths

v. Bed and head joint depth: Remove old mortar to a depth of 2 to 2 ½ times the width of the joint to ensure an adequate bond.

D. Brick masonry specifications:

vi. Standard requirements: Brick masonry units must comply with ASTM C 216 – 17a Standard Specifications for Facing Brick

vii. Brick type: FBS

viii. Brick grade: SW

ix. Brick color: Red

x. Brick edge: Tumbled

xi. Brick dimensions:

1. Width: Approximately 3 ½”

2. Height: Approximately 2 – 1/4”

3. Length: Approximately 7 - 7/8”

xii. Intent: The intent is to match the brick dimensions and brick colorations of the bricks used on the bakery oven.

E. Bakery oven alignment, and style requirements: Bakery oven and chimney should be constructed to replicate existing alignments, dimensions, and styles (layering of courses)

Note: All brick masonry and stone masonry work performed is not required to receive a paint treatment after the work is performed. This work will be performed by others.

V. General Conditions A. Use of utilities:

i. The contractor must provide their own water and electric utility. The use of generators is permitted.

ii. There are existing privies located on the site which the contractor may use. The privies will also remain available for public use.

B. Work hours:

i. The contractor may work Monday – Thursday from 8:00 a.m. until 8:00 p.m. The contractor may work Friday from 8:00 a.m. until 4:30 p.m. No work may be performed on Saturdays or Sundays.

ii. In addition to no work on Saturdays and Sundays, no work may be performed on the following dates in the year 2018: September 3rd, September 17th, and September 18th.

C. Responsibility of protecting work and adjacent materials:

i. The Contractor is responsible for protecting their work from the visiting public and from the elements of weather. The contractor shall supply the necessary tools and equipment to protect the work from the public & elements of weather until a quality mortar cure is established.

ii. The Contractor is responsible for protecting all adjacent materials from damage resulting from their work including but not limited to: Siding, flashing, brick and stone masonry to remain in place, roofing, windows, doors, decks and other historic building features.