09720 WALLPAPER CONSERVATION AND RESTORATION

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SECTION 09720 – WALLPAPER CONSERVATION AND RESTORATION

PART 1 - GENERAL

1.1    RELATED DOCUMENTS

A.    Drawings and general provisions of the Contract, including General and Supplementary Conditions and Division 1 Specification Sections, apply to this Section.

1.2    SUMMARY

A.    This Section includes the following:

1.    Wallpaper removal.
2.    Removal of adhesives and disinfecting of plaster prior to painting.
3.    Surface repairs to plaster.
4.    Wallpaper conservation including cleaning, consolidation, and reattachment.
5.    Wallpaper replication.
6.    Selection and installation of authenticated period wallpaper.

B.    Related Sections include the following:
1.    Division 9 Section "Plaster Conservation” for structural repairs to existing plaster.

C.    Intent:  The intent of the wallpaper conservation is to remove layers of wallpaper that post-date the property’s period of significance, while retaining and conserving  papers dating to the period of significance (“Project Restoration Period”) .  See Appendix – Pre-Treatment Assessment for analysis of significant papers.

1.    The removal of outer layers of paper may reveal papers that have not been previously documented.  Great care must be taken during removal of later papers so the remnants of earlier paper are salvaged in a way that they can be documented.  If the papers are determined to be Project Restoration Period papers, the wallpaper fragments will be conserved in-situ.
2.    If it is not possible to successfully remove outer layers without damaging lower layers, the wallpaper “sandwich” may be removed from the wall and separated in the conservation laboratory.  Project Restoration Period  papers will be reattached to the wall in the exact locations in which they were discovered.
3.    Areas of distemper surface finishes should be tested for cleaning methods which avoid the use of water, such as ethanol, prior to undertaking wallpaper removal or cleaning in these areas.

1.3    SUBMITTALS

A.    Product Data:  For each type of product indicated.   Include MSDS sheets.

B.    Qualification Data:  Qualification data for firm and personnel specified in “Quality Assurance” Article that demonstrates that both firm and personnel have capabilities and experience complying with requirements specified.  Provide list of at least three (3) completed projects of similar size and scope to work required on this project.  For each project list project name, address, architect, conservator, supervising preservation agency, and  scope of work. 

C.    Conservation Treatment Program:  
1.    Include a detailed description of materials and methods to be used for each phase of wallpaper conservation.

D.    Wallpaper Documentation:  Provide documentation of visible and uncovered wallpaper layers for project documentation.  Document locations of all papers.

E.    Wallpaper Investigation Report:  Review Historic Structure Report wallpaper analysis, exposed mid-nineteenth century wallpaper remaining in place, and samples of mid-nineteenth century wallpapers found within the third floor restoration zone spaces to provide recommendations for selection of authentic, period-appropriate wallpapers to be installed in restoration spaces where samples of wallpaper dating to the Project Restoration Period have been found but no longer remain in place. Also provide recommendations for filling in gaps in surfaces such as the dividing wall of room 9, where a complete pattern remains in place but substantial areas of wallpaper are missing. 

F.    Complete pattern design for filling in gaps in the [list room locations, e.g. third floor hallway and small parlor], where wallpaper fragments dating to the Project Restoration Period remain in place but do not provide a complete pattern for reproduction to cover surfaces where plaster or wallpaper is missing, and provide surface continuity.  Pattern design should incorporate extant fragments remaining in place.  Pattern completion should reflect current knowledge of wallpaper design and technology in use and available during the Project Restoration Period.  

G.    Wallpaper samples: Provide samples showing complete pattern and colors for areas to receive documented, commercially available reproduction wallpapers as well as replica wallpaper developed from wallpaper fragments.  

1.4    QUALITY ASSURANCE

A.    See Division 1 "Competency of Architectural Conservator" and  “Competency of Wallpaper Conservator” for qualification requirements.

B.    Documentation:  The discoveries of previously unanalyzed wallpapers must be documented.
C.    

Mockups:  Provide mockups for each type of process.
1.    Removal of wallpaper.
a.    One layer on top of another layer.
b.    Removal of base layer and surface preparation to remove adhesive and disinfect plaster.
2.    Plaster consolidation.
3.    Wallpaper cleaning.
4.    Wallpaper consolidation.
5.    Wallpaper reattachment.  
6.    Reproduction wallpaper installation, demonstrating historic methods of laying wallpaper.
7.    Infill wallpaper placement  around cleaned and secured fragments, including, if deemed necessary by the Historical Architect/ Conservator , toning in of new surfaces to achieve reasonable surface continuity without completely obscuring the distinction between historic and recreated surfaces.  

D.  Knowledge of Site:  Bidders must visit project site before submitting bid and make themselves thoroughly familiar with specific conditions relating to this Section.  Submission of bid shall be considered acknowledgement that Contractor is familiar with existing site conditions affecting work of this Section.

1.5    PROJECT CONDITIONS

A.    Environmental Limitations:  Do not undertake conservation work until wet work in spaces is complete and dry, work above ceilings is complete, and ambient temperature and humidity conditions are maintained at the levels indicated for Project when occupied for its intended use.
B.    Lighting:  Do not undertake wallpaper conservation until a lighting level of not less than 15 fc is provided on the surfaces to receive wall covering.
C.    Ventilation:  Provide continuous ventilation during conservation work.
D.    Laws and Regulations:  Perform work of this Section in compliance with all applicable federal, state, and local laws and regulations.
E.    Protection of Persons:  Take all necessary measures to protect all persons, whether or not involved with work of this Section, from harm caused by work of this Section.
F.    Protection of Building:  Protect building elements and finishes from damage or deterioration caused by work of this Section using all means necessary.  Repair any damage to materials or finishes to Architect’s satisfaction at no additional cost to Owner.

1.    Take all necessary precautions to prevent fire or spread of fire.

PART 2 - PRODUCTS

A.    Products:  Subject to compliance with requirements, provide one of the products listed in Part 2 "Wall-Covering Products" Article.

B.    Replica wallpaper (custom designed pattern):  Shall accurately reproduce original wallpaper design, colors, texture, and other visual qualities, completing missing portions of the pattern as authentically as possible, based on wallpaper patterns in use at the time. 

C.    Reproduction wallpaper (commercially available patterns):  Shall authentically reproduce wallpapers documented as available during the Project Restoration Period. Manufacturers shall be established as specialists in the authentic reproduction of historic wallpapers. WALLPAPER

D.    Dry Cleaning Sponge:  Vulcanized natural rubber.  Available from Talus 212-219-0770.

E.    Denatured alcohol.  Pure 180 proof denatured alcohol.  Provide E-Z Alcohol, as manufactured by E. E. Zimmerman Co., Pittsburgh, PA, or approved equal.

F.    1:1 solution of ethanol and water.

G.    BEVA D-8 Dispersion, by Conservator’s Products Company 973-927-4855.

H.    BEVA Gel, by Conservator’s Products Company 973-927-4855.

I.    BEVA 371 Solution, by Conservator’s Products Company 973-927-4855.

2.2    WALLPAPER CONSERVATION ACCESSORIES

A.    Japanese tissue paper, Available from Talus 212-219-0770.

B.    Plaster disinfectant: ShockWave

PART 3 - EXECUTION

3.1    PRELIMINARY RESEARCH

A.    Review Conservation Study finishes analysis.

B.    Examine exposed wallpaper fragments, samples collected from Restoration Zone spaces, and recommended commercially available reproduction wallpapers.

C.    Provide specific recommendations for selection of commercially available, documented reproduction wallpapers in most restoration zone spaces and for recreating original wallpapers from fragments in third floor hallways..

3.2    EXAMINATION

A.    Examine substrates prior to undertaking conservation work.  Plaster must be sound and the surface hard, not friable or dirty.

B.    Proceed with treatments only after unsatisfactory conditions have been corrected.

C.    Follow protocols outlined in Wallpapers in Historic Preservation, NPS HPS 1997. 

3.3    PATTERN DEVELOPMENT AND SELECTION

A.    Oversee development of wallpaper patterns for third floor hallways and Room 9 parlor where historic wallpaper fragments remain visible. Follow methodology described in APT Bulletin XXXIX, No. 4. 

1.    Patterns shall be developed digitally to reduce production costs and allow the owner to maintain a complete copy of the design for future reference or restoration. 

B.    Work with Historical Architect to select commercially available reproduction patterns for other restoration zone locations where original wallpapers no longer remain in place. 

C.    Report: Prepare and submit a report summarizing study findings and recommendations for pattern development and period wallpaper selection. 

3.4    WALLPAPER REMOVAL

A.    Spray ethanol solution on the surface of the wallpaper layer to be removed.  

B.    Steam paper to soften adhesive.   

C.    Gently remove outer layer from layers of wallpaper below.

D.    Document wallpaper layers below surface layer.

E.    Continue, as determined by Architect in the field.

3.5    REMOVAL OF ADHESIVES FROM PLASTER 

A.    Clean surface of plaster with razor scraper as required to remove remnants of paste and wallpaper.

B.    Clean exposed plaster with ShockWave to disinfect plaster and remove adhesive residue.  

3.6    SURFACE REPAIRS TO PLASTER PRIOR TO WALLPAPER CONSERVATION

A.    Clean plaster of dirt using a brush or dry sponge eraser.  
1.    Brush dirt and loose surface plaster off with a soft brush 
2.    Clean plaster with dry sponge eraser

B.    If plaster surface is friable, consolidate with BEVA D-8.  
1.    Brush diluted BEVA D-8 on friable plaster.

3.7    REATTACHMENT OF WALLPAPER AT CEILING REPAIRS

A.    In areas where recessed screws and washers have been installed to secure ceiling plaster, use the following procedure to hide the hardware.
1.    Note:  Ceiling wallpapers should be torn away and salvaged for reattachment by paper conservator prior to the installation of the plaster screws and washers by the plaster conservator.
a.    The piece removed should have an irregular edge so that it blends better when replaced;
b.     The washer and screw should be covered first with Japanese paper, then the wallpaper replaced over the Japanese paper.  This will make a stronger and more invisible repair to the area.

3.8    WALLPAPER CLEANING

A.    The presence of dirt and mold together means that extra precautions should be taken in removing surface dirt.  The walls and ceilings should be vacuumed with a HEPA filter.

1.    Prepare the hose of the vacuum cleaner by tying a piece of screening over the nozzle to prevent loose paper from being sucked into the hose
2.    Using disposable brushes, direct the surface dirt into the vacuum cleaner hose
3.    Discard the brushes when they become soiled

B.    After loose dirt and mold spores have been removed, the paper should be cleaned with eraser.
1.     Prepare pieces of dry sponge eraser by cutting the larger sponge into blocks 1-1/4” x 3” x 1-3/4” cut a block of sponge into about five pieces.
2.    Clean the paper in regular grids so that the degree of cleaning can be controlled
3.    Clean with light, even strokes first down, then sideways for even coverage
4.    The number of strokes over any one area should be four to no more than six
5.    Dirty sponge should be discarded and fresh sponge used when the accumulation is a medium gray color.

3.9    READHESION OF MULTIPLE LOOSE LAYERS OF WALLPAPER

A.    For large areas difficult to access, BEVA 371 can be injected using a large plastic syringe used by wallpaper installers.  It may be necessary to make a small incision in the paper first.  The adhesive should be injected at the top of the air pocket and worked down, being careful not to damage the paper on top.
1.    The BEVA 371 must be diluted with xylene or naphtha to a consistency that can be used in a syringe.
2.    Sometimes a larger incision in the paper must be made and the paper folded back to reveal the plaster or lower wallpaper.  
a.    Assess the size and shape of the air pocket
b.     If there is loose material collected at the bottom of the air pocket, cut the paper at the bottom of the air pocket and along one side
c.    Brush out the loose material
d.     If necessary, consolidate the plaster surface
e.    Brush BEVA 371 on the plaster or wallpaper
f.     With a soft, wide brush, starting opposite the cut side, brush the paper down and the air out of the air pocket
g.    If the paper is not completely adhered, the BEVA can be softened up with a tacking iron in order to make it tacky again and the paper can be pressed down.  BEVA 371 softens at about 180 degrees Fahrenheit.

3.10    REPAIRING LOOSE EDGES

A.    Free edges of paper can be adhered by slipping a bit of BEVA Gel or BEVA 371 under the edge using a small brush or an artist’s palette knife, which is very thin.   The edge is then pressed into place.   Large globs of gel will leave water stains and lumps under the paper, so only the least amount necessary can be used.
1.    Using a triangular-shaped palette knife which comes to a rounded point, pick up a thin layer of BEVA Gel on the edge
2.    Holding the knife at an angle, lift the edge of the paper and apply the gel along the edge
3.    Remove any excess along the edge with the knife
4.    Using a soft paper towel, press the loose paper edge back down to the wall
5.    Constantly refold the towel after use so that no gel is deposited on the surface of the wallpaper
6.    Remove any BEVA on the surface with naphtha or xylene

3.11    REATTACHMENT OF HANGING PAPERS

A.    Reattaching hanging paper requires softening the paper to that it will bend back into position without breaking.  This can only be done with some moisture, in spite of the danger of creating more tide lines or drying stains.
1.    Prepare the plaster surface by cleaning and consolidating if necessary
2.    Lightly spray the back of the hanging paper using a 1:1 solution of ethanol and water until the bend feels flexible
3.    Brush BEVA D-8 or BEVA 371 onto the plaster
4.    With a soft paper towel, push the hanging paper back into place

3.12    MOLD REMOVAL FROM WALLPAPER OF LIMITED SCOPE

A.    Gentle conservation with denatured alcohol is recommended in areas where there is limited mold on the surface of the paper.

3.13     PERIOD WALLPAPER INSTALLATION

A.    Install reproduction wallpapers to recreate the appearance of the spaces during the Project Restoration Period as authentically as possible, retaining and readhering, as necessary, original fragments that remain in place or can be readhered. 

B.    Carefully install reproduction wallpaper around cleaned and secured fragments in hallways., including, if deemed necessary and appropriate by the supervising Historical Architect, toning in of new surfaces to achieve reasonable surface continuity without completely obscuring the distinction between historic and recreated surfaces.  

END OF SECTION 09720