Case Study & Photographs of Paint Failure on a Wood-Sided Building InspectAPedia® -
Field & Lab photographs re Private Party Paint Failure Report 10/9/2006 - Daniel Friedman: forensic paint analysis lab & field studies on buildings and in artworks
These onsite paint failure photographs help explain the cause of paint peeling, cracking, chalking, and other paint problems on buildings
How to sort through arguments and blame when the paint job on a building fails miserably: peeling, cracking, falling off of painted wood surfaces.
Demonstration of a paint-adhesion test: procedures, photographs
Questions & answers about diagnosing the cause of paint troubles
Paint failure inspection, diagnosis, and remedy case study: this document presents field and lab annotated photographs of severe paint failure on a wood sided pre-1900 building in New York.
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After a painter skim-coated old paint on the wood siding using 40 gallons of Sherwin Williams C-70 crack and hole filler (not a recommended use of this product), a rapid and extensive failure of the new painted surfaces was evident in less than 90 days. Readers should also see Paint Failure Case Photographs-SITE and then Paint Failure Case Photographs-LAB, and see PAINT & STAIN GUIDE, EXTERIOR for a guide to the selection and proper application of paints and stains on exterior wood surfaces.
Extensive stripping and surface preparation will be required to restore the building. The skim-coat product, a substance intended for small crack and hole filling, was used in violation of the manufacturer's instructions.
Paint Failure Site Photos (selected) - numbers refer to citations in lab sample table
-- Daniel Friedman
The accompanying photographs taken in our forensic lab provide examples of paint contaminants or other conditions associated with paint failures that can be of assistance to analysts investigating paints on buildings, artifacts, and works of art.
Pre-1900 wood sided building in New York's Hudson Valley, site photo providing context for the close-up photographs of exterior paint problems shown below.
Site 025 loose, alligatored paint low on walls, an insecure surface that needed to be stripped prior to painting.
Site 031 surface of wood clapboard below loose falling-off alligatored paint - this condition was not visible in most areas due to the skim-coating.
Site 032 Demonstrating that skim coat was applied over loose failing and alligatored paint on the building exterior wall
Site 034 wall surface below failed paint. The light colored wood in lower photo has been exposed to weather following paint failure.
Site 035 shows improper use of skim coat material at clapboard butt joint -specifically advised-against by the coating manufacturer.
Site 036 shows loose falling off skim coat and paint at clapboard butt joint
Site 039 preparing an adhesion test in the painted surface near a failed butt joint
Site 043 paint adhesion test in process
Site 044 paint adhesion test in process
Site 048 paint adhesion test showing removal of new paint from old surface, varying by closeness of the razor cuts
Site 050 example of vertical crack in skim coated material; also note the pattern of paint finish indicating that a paint roller was used to apply paint.
Site 052 preparing an investigative razor cut to the right of a pre-existing vertical crack in skim coated painted building
Site 054 exploring vertical crack in skim coated painted building
Site 059 depth of skim coat plus old and new paint exceeds 2mm
Site 064 evidence of painting over dirt on siding low on building walls
Site 067 failure of edge of skim coat over old paint
Site 069 measuring depth of failed skim coat and paint on building wall
Site 070 skim coat and new paint falling off reveal adhered older paint layers, confirming that paint failure was not due to moisture push from building interior conditions
Site 071 back surface of failed paint chip can be examined for evidence of failure cause
Site 078 example of failure in skim coat painted surface
Site 079 example of failure of skim coated over clapboard butt joint
Site 081 example of horizontal cracking in coating applied over clapboards before painting
Site 083 probing multiple cracks in painted surface
Site 084 new paint adhesion failure over skim coat
Site 091 example of thick skim coat over loose old paint
Site 092 example of thick skim coat over loose old paint - detail
Site 095 measuring long horizontal crack failure in painted building exterior
Site 096 probing horizontal crack in painted skim coat on building exterior - to 10mm of loose paint
Site 097 crumbling skim coated crack filler on building exterior leads to paint failure; note dirt and debris, possibly mold growth between layers of material
Site 100 probing horizontal and vertical paint crack failure
Site 101 paint failure example on building exterior wall
Site 106 paint failure example - paint falling off of building over skim coat
Site 109 one of the paint products used - the skim coat of crack filler (Sherwin Williams C-70 not applied according to manufacturer's instructions) was the root cause of paint failure on this building, not the choice of primer nor top coat of paint.
Site 123 skim coat and paint failing over building trim
Site 124 skim coat and paint failing over building trim
Site 128 skim coat and paint failing over building trim
Site 130 probing thick skim coat failure - note older paint remaining adhered to surface - area was "touched up" after peeling paint began
Site 146 sidelight shows skim coating over irregular alligatored and cracked loose paint on clapboards - failing within 90 days of application
Site 147 sidelight shows skim coating over irregular alligatored and cracked loose paint on clapboards - failing within 90 days of application
Site 149 crumbling skim coating painted-over is failing and releasing paint from surface
Site 150 crumbling skim coating painted-over is failing and releasing paint from surface
Site 154 typical example of multiple shrinkage cracks in skim coat applied to building exterior as a shortcut where surface preparation was omitted
Site 156 skim coat and paint failure below clapboard edge
Site 157 paint failure showing older adhered paint layer below confirms that interior building moisture was not a prime cause of lost paint on this surface
Site 161 test cut to bare wood
Site 172 probing failing paint on building exterior walls
Site 177 probing failing paint on building exterior walls
Site 182 probing failing paint on building exterior walls - note mold growth on back of paint chip
Site 185 documenting thickness of skim layer
Site 189 documenting depth of skim layer on trim
Site 192 documenting condition of failing paint coating on building exterior trim
Site 195 documenting condition of failing paint coating on building exterior trim
Site 201 documenting condition of failing paint coating on building exterior trim
Site 203 documenting condition of failing paint coating on building exterior trim
Site 205 documenting condition of failing paint coating on building exterior trim
Site 208 typical horizontal crack failures in exterior paint coating on wood clapboards - paint applied over C-70 skim coat
Site 211 typical paint failures in exterior paint coating on wood clapboards - paint applied over C-70 skim coat
Site 212 mold on back of paint chip can indicate inadequate surface cleaning prior to painting but in this case it is primarily due to moisture penetration of the paint layers
Site 219 cracking exterior paint over skim coat
Site 220 cracking exterior paint on wood wall
Site 222 probing loose exterior paint
Site 242 probing loose exterior paint
Site 243 probing loose exterior paint
Site 245 probing loose exterior paint
Site 246 probing loose exterior paint
Site 281 test boards preserved from building exterior demonstrate improper surface preparation and skim coat basis of extensive paint failure
Site 282 test boards preserved from building exterior demonstrate improper surface preparation and skim coat basis of extensive paint failure
Site 288 test boards preserved from building exterior demonstrate improper surface preparation and skim coat basis of extensive paint failure
Site 289 test boards preserved from building exterior demonstrate improper surface preparation and skim coat basis of extensive paint failure
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Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair
Our recommended books about building & mechanical systems design, inspection, problem diagnosis, and repair, and about indoor environment and IAQ testing, diagnosis, and cleanup are at the InspectAPedia Bookstore. Also see our Book Reviews - InspectAPedia.
Analysis of Modern Paints, Thomas J.S. Learner, Research in Conservation, 2004 ISBN 0-89236-779-2 [Chemistry of modern paints, overview of analytical methods, pyrolysis-gas chromatography signatures of basic modern paints and their constituents, Fourier transform infrared spectroscopy for paint analysis, direct temperature-resolved mass spectrometry, and analysis in practice - technical reference useful for forensic paint science, focused on art works -DF]
Paint and Surface Coatings, Theory and Practice [purchase at Amazon.com], R. Lambourne & T.A. Strivens, Ed., Woodhead Publishing Ltd., William Andrew Publishing, 1999 ISBN 1-85573-348 X & 1-884207-73-1 [This is perhaps the leading reference on modern paints and coatings, but is a difficult text to obtain, and is a bit short on field investigation methods - DF]
Paint Handbook: testing, selection, application, troubleshooting, surface preparation, etc., Guy E. Weismantel, Ed., McGraw Hill Book Company, 1981, ISBN-10: 0070690618, ISBN-13: 978-0070690615, [Excellent but a bit obsolete paint theory and practice, also a bit light on field investigation methods, out of print, available used-DF] How to select and apply the right paint or coating for any surface. The first major reference to help you choose the correct paint or other finish to do the job best on a particular surface exposed to a particular environment. Experts in the field give full advice on testing surface preparation, application, corrosion prevention, and troubleshooting. The handbook covers wood, metal, composites, and masonry, as well as marine applications and roof coatings. A ``must'' working tool for contractors, architects, engineers, specification writers, and paint dealers.
Paint and Surface Coatings, Theory and Practice, R. Lambourne & T.A. Strivens, Ed., Woodhead Publishing Ltd., William Andrew Publishing, 1999 ISBN 1-85573-348 X & 1-884207-73-1 [This is perhaps the leading reference on modern paints and coatings, but is a difficult text to obtain, and is a bit short on field investigation methods - DF] Provides a comprehensive reference source for all those in the paint industry, paint manufacturers and raw materials suppliers, undergraduate and postgraduate students, and industrial paint users. R. Lambourne was in the Research Department at ICI Paints Division and the Industrial Colloid Advisory Group, Birstol University, UK.
Seeing Through Paintings, Physical Examination in Art Historical Studies, Andrea Kirsh, Rustin S. Levenson, Materials in Fine Arts, 2000 ISBN 99-051835 [ forensic science, technical reference, focused on art works - DF]
Sealants, Durability of Building Sealants (RILEM Proceedings), J.C. Beech, A.T. Wolf, Spon Press; illustrated edition (1995), ISBN-10: 0419210709, ISBN-13: 978-0419210702 This book presents the papers given at the RILEM Seminar held at the Building Research Establishment, Garston, UK in October 1994. The book provides an opportunity for researchers to review up-to-date progress towards the achievement of the objectives of the standardisation of laboratory techniques of sealants in the variety of service conditions to which they are exposed.
Soiling and Cleaning of Building Facades (RILEM Report), L.G.W. Verhoef (Editor), Routledge; 1 edition (November 3, 1988), ISBN-10: 0412306700, USBN-13: 978-0412306709 The report of a comprehensive investigation by RILEM which examines all aspects of the cleaning of facades, subject to soiling by both biological and non-biological agencies. The contributors are international authorities working in this field giving essential advice to all those who need to know how to approach the problems connected with the soiling and cleaning of building facades.
Staining, Prevention of Premature Staining in New buildings, Phil Parnham, Taylor & Francis; 1996, ISBN-10: 0419171304, ISBN-13: 978-0419171300 The appearance of ugly staining early in a buildings life, ruins an otherwise pleasing appearance, tarnishes the image of the owners and gives rise to costly refurbishment works. In this book Phil Parnham raises a number of questions that should be considered whenever a new building is being designed or built. These are: * why has staining become so prominent; * what causes premature staining; which parts of new buildings are likely to be affected; * how can it be avoided? By using a number of highly illustrated case studies, the author answers these questions and ends by suggesting measures that should be taken by all design and construction professionals to prevent premature staining.
Understanding Ventilation, John Bower, The Healthy House Institute, ISBN 0-9637156-5-8, 1995 [General building science-DF - ** Particularly useful text. Mr. Bower has retired from the field but his book continues to be important]
"Moisture Control in buildings: Putting Building Science in Green Building," Alex Wilson, Environmental Building News, Vol. 12. No. 5. [Good tutorial, "Moisture 101" outlining the physics of moisture movement in buildings and a good but incomplete list of general suggestions for moisture control - inadequate attention given to exterior conditions such as roof and surface drainage defects which are among the most-common sources of building moisture and water entry.--DJF]
Analysis of Modern Paints, Thomas J.S. Learner, Research in Conservation, 2004 ISBN 0-89236-779-2
[Chemistry of modern paints, overview of analytical methods, pyrolysis-gas chromatography signatures of basic modern paints and their constituents, Fourier transform infrared spectroscopy for paint analysis, direct temperature-resolved mass spectrometry, and analysis in practice - technical reference useful for forensic paint science, focused on art works. One of our most useful texts in forensic investigation of paint failures and paint problem diagnosis - for building investigators as well as art conservators. -DF]
Although oil remains an important binding medium in artists' paints, today's synthetic resins are being used with increasing frequency. This was true during much of the twentieth century, when artists such as David Alfaro Siqueiros, Jackson Pollock, and Pablo Picasso used commercial or industrial paints based on synthetic resins. The growing popularity of synthetic resin materials carries important implications for the conservation, preservation, and treatment of modern art.
This volume outlines the techniques that are currently employed to analyze the synthetic resins used in modern painting materials, such as pyrolysis-gas chromatography-mass spectrometry, Fourier Transform infrared spectroscopy, and direct temperature-resolved mass spectrometry. For each technique, results are given for standard samples of the principal classes of synthetic binding media, various pigments and extenders, tube paint formulations, and microscopic paint fragments taken from actual works of art.
Primarily intended for conservation scientists, conservators, researchers, and students of conservation, this book will also be of interest to other museum professionals.
Art, Biology, and Conservation: Biodeterioration in Works of Art, Robert J. Koestler et als. Eds., Metropolitan Museum of Art, 2003, ISBN 1-58839-107-8 Series of excellent research and advice articles on art work conservation of special use to conservators and also to building, artifact, and art forensic investigators. MOMA. - DF
Despite the perception that artworks are timeless and unchanging, they are actually subject to biological attack from a variety of sources—from bacteria to fungi to insects. This groundbreaking volume, which publishes the proceedings of a conference held at The Metropolitan Museum of Art in 2002, explores how the development of these organisms can be arrested while preserving both the work of art and the health of the conservator.
The richly illustrated text, containing the writings of over 40 scientists and conservators, is divided into sections on stone and mural paintings, paper, textiles, wood and archaeological materials, treatment and prevention, and special topics. The artworks and cultural properties discussed include, among many others, Paleolithic cave paintings, Tiffany drawings, huts built by early Antarctic explorers, and a collection of toothbrushes taken from Auschwitz victims. --
Robert J. Koestler is a research scientist at The Metropolitan Museum of Art; Victoria H. Koestler is a freelance writer and editor; A. Elena Charola is a freelance conservation scientist; and Fernando E. Nieto-Fernandez is a biologist at Old Westbury College, New York.
Cultural Heritage and Aerobiology, Methods and Measurement Techniques for Biodeterioration Monitoring, Paolo Mandrioli, Guilia Caneva, and Cristina Sabbioni, Eds., Kluwer Academic Publishers, 2003 ISBN 1-4020-1622-0 This is a translated and revised edition of the original Italian version. This book is the first to give a general overview of the application of aerobiology (the science that studies the biological components of the atmosphere) to the conservation of our cultural heritage. Aerobiological monitoring makes it possible to estimate the risks of degradation of artefacts of historical or artistic importance by airborne microorganisms (airborne spores and vegetative structures) according to the types of materials forming the artefacts, to the conditions of the microclimate and to the type of environmental pollution, thus enabling the planning of preventive or reparative intervention. Among the book's main features are: + Aspects of the biodeterioration of different materials (paper, wood, fabrics, parchment, leather, stone, glass, metals, plastic, etc.). + Methods for measuring environmental parameters, both physical (microclimatic) and chemical (pollutants). + Methods and techniques of aerobiological monitoring. + Specific problems concerning the different types of environments. Audience: The subject is thoroughly explored, thus supplying a useful tool to those who are in charge of the conservation of our cultural heritage (libraries, archives, museums, churches, hypogea, monuments, archaeological sites, etc.). See our book review of this reference.
Exterior Paint Problems on Historic Woodwork, Kay D. Weeks and David W. Look, AIA, U.S. Department of the Interior, National Parks Service Preservation Brief No. 10. Web search 02/01/2011, original source: http://www.nps.gov/hps/tps/briefs/brief10.htm
Microscopy of Textile Fibres (Microscopy Handbooks, 32), P H Greaves, Garland Science; 1 edition (January 1, 1995), ISBN-10: 1872748244, ISBN-13: 978-1872748245 [We ordered our copy from the British publisher - now it's on Amazon.
These 3 fiber books have been essential forensic lab references supplementing our McCrone Research courses on forensic microscopy; also of use to textile conservators. - DF
An up-to-date practical guide to the properties and characteristics of textile fibres, with clear advice on sampling, specimen preparation and examination procedures.
Modern Paints Uncovered (Getty Conservation Institute Symposium Proceedings), Thomas Learner, Getty Publications (March 1, 2008),ISBN-10: 089236906X, ISBN-13: 978-0892369065 Over the past seventy years, a staggering array of new pigments and binders has been developed and used in the production of paint, and twentieth-century artists readily applied these materials to their canvases. Paints intended for houses, boats, cars, and other industrial applications frequently turn up in modern art collections, posing new challenges for paintings conservators.
This volume presents the papers and posters from "Modern Paints Uncovered," a symposium organized by the Getty Conservation Institute, Tate, and the National Gallery of Art and held at Tate Modern, London, in May 2006. Professionals from around the world shared the results of research on paints that have been available to artists since 1930--the date that synthetic materials began to significantly impact the paint industry.
Modern Paints Uncovered showcases the varied strands of cutting-edge research into the conservation of contemporary painted surfaces. These include paint properties and surface characteristics, analysis and identification
Paint Handbook: testing, selection, application, troubleshooting, surface preparation, etc., Guy E. Weismantel, Ed., McGraw Hill Book Company, 1981
[Excellent but a bit obsolete paint theory and practice, also a bit light on field investigation methods, out of print, available used. Very useful reference for paint testing, selection, and paint failure diagnosis - focus on non-artistic use of paints such as on buildings, roofs, marine coatings. -DF]
How to select and apply the right paint or coating for any surface. The first major reference to help you choose the correct paint or other finish to do the job best on a particular surface exposed to a particular environment. Experts in the field give full advice on testing surface preparation, application, corrosion prevention, and troubleshooting. The handbook covers wood, metal, composites, and masonry, as well as marine applications and roof coatings. A ``must'' working tool for contractors, architects, engineers, specification writers, and paint dealers
Paint Magic, Jocasta Innes, Frances Lincoln; 4th edition (August 17, 2006), ISBN-10: 071122272X, ISBN-13: 978-0711222724 - Paint advice for home decoration, including painting techniques such as antiquing, bambooing, bleaching, color washing, combing, decorative painting, dragging, dyeing, gliding, graining, japanning, lacquering, lining, marbling, porphyry, rag-rolling, sponging, staining, stencilling, stippling, tortoiseshelling, trompe l'oeil, and vinegar painting - DF
Paint and Surface Coatings, Theory and Practice - [purchase at Amazon.com], R. Lambourne & T.A. Strivens, Ed., Woodhead Publishing Ltd., William Andrew Publishing, 1999 ISBN 1-85573-348 X & 1-884207-73-1
[
This is perhaps the leading reference on modern paints and coatings, but is a difficult text to obtain, and is a bit short on field investigation methods. Encyclopedic reference on the composition, production, properties, use, and testing of paints and coatings - DF]
Provides a comprehensive reference source for all those in the paint industry, paint manufacturers and raw materials suppliers, undergraduate and postgraduate students, and industrial paint users.
Quality Assessment of Textiles, Karl Marshall, Kindle Edition, Springer; 2nd edition (October 31, 1993, ASIN: B00193F3BI The damage which can occur in certain fibrous raw materials or during the production and storage of textiles is expertly described in this book by Karl Mahall. He particularly shows how to find concealed textile defects by using microscopic analysis. The examples represent typical cases that the author encountered during forty years of experience in the industry. Well-illustrated with impressive photographs, they invite you to follow each step and learn to apply the same methodology in practice. This book is especially useful as a manual for both chemical and textile engineers and quality engineers. It is also a useful reference for others in the textile industry in general.
Seeing Through Paintings, Physical Examination in Art Historical Studies, Andrea Kirsh, Rustin S. Levenson, Materials in Fine Arts, 2000 ISBN 99-051835 [ forensic science, technical reference, focused on art works - DF]
One of the best texts available for forensic investigation of the history, authenticity, and condition of paintings - DF
Understanding Ventilation, John Bower, The Healthy House Institute, ISBN 0-9637156-5-8, 1995 [General building science-DF - ** Particularly useful text. Mr. Bower has retired from the field but his book continues to be important]
"Moisture Control in buildings: Putting Building Science in Green Building," Alex Wilson, Environmental Building News, Vol. 12. No. 5. [Good tutorial, "Moisture 101" outlining the physics of moisture movement in buildings and a good but incomplete list of general suggestions for moisture control - inadequate attention given to exterior conditions such as roof and surface drainage defects which are among the most-common sources of building moisture and water entry.--DJF]
Why House Paint Fails [on file as /exterior/Why_House_Paint_Fails_FPL1.pdf ] - , Mark Knaebe, US FPL, web search August 2010, original source: http://www.fpl.fs.fed.us/documnts/finlines/knaeb95a.pdf
Why Paint Jobs Fail [on file as /exterior/Why_Paint_Fails_Bennett.pdf ] - , web search, August 2010, original source: http://www.bennette.com/pdf/whyfail.pdf, four pages describing alligatoring, bleeding, blistering, etc. Bennette Corporation, P.O. Box 9088, Hampton, VA 23670, Phone: 757-838-7777, Toll Free: 800-869-2929
Fax: 757-827-0529, Email: info@bennette.com, Website: www.bennette.com quoting: Bennette Paint Manufacturing Company, Inc. is a Virginia corporation which was founded in Newport News, Virginia in 1966 by James P. Bennette, Sr. In 1984, Mr Bennette sold the company to his employees through an Employee Stock Ownership Plan (ESOP). Today the company has a modern manufacturing plant, research laboratory, central warehouse and general offices located at 401 Industry Drive, Hampton, Virginia. From these facilities the company is able to supply quality paints and coatings through its company owned distribution and service centers and authorized dealers located in Virginia, North Carolina and South Carolina. Bennette Paint Manufacturing Company, Inc. also owns and operates Bennette Equipment Company which specializes in the sale, service, and rental of paint spraying and pressure cleaning equipment.
Supplemental Guidelines for Removing Paint From Interior and Exterior Wood Surfaces [on file as "/exterior/Paint_Removal_USGSA.pdf ] - , US General Services Administration, Historical Preservation Technical Procedures, 06400-02, web search August 2010, original source: //w3.gsa.gov/web/p/Hptp.nsf/0/40aff5a115b6a9e5852565c50054b4f4?OpenDocument
"Peeling Back Paint Layers For a Glimpse Into the Past," James Barron, The New York Times, 25 Feb 2010, p. A26
"Staining and Microbiological Infestation of Acrylic Paintings on Hardboard", Ulrik Runeberg, Conservator (Dipl. Rest./M.A.), Museo de Arte Contemporáneo de Puerto Rico, San Juan Presented,April 2007 conference in Richmond Virginia, sponsored by the AIC (American Institute for Conservation), this paper discussed the staining and microbial infestation of acrylic paintings on hardboard. - private correspondence, ER <->DF 12 September 2006. The following quotation is from the paper's abstract: "Hardboard served as a common and popular support for many modern paintings that were carried out from the mid - 1920’s, and still is used occasionally in contemporary art. Many artists rejected hardboard as an inferior industrial construction material of low aesthetical value, whereas others considered the processed and compressed wood fiber boards to be a stable, light and economic alternative to solid wood panels and other rigid supports. "From the conservator’s critical point of view, the many disadvantages of this type of support include: high acidity, hygroscope characteristics, tendency of ‘off-gassing’, (>tendency of) warping, occasional flaking of painting material in the case of tempered hardboard. The deterioration of paintings on hardboard depends on a number of factors including: the quality of the hardboard, prevailing storage conditions, and the preparation of the support by the artist. While there are many paintings on hardboard that are in very good condition, this paper will focus on those paintings that are heavily deteriorated and damaged. "A very characteristic damage found on porous painting layers such as acrylic colour on hardboard, is the formation of stains. Generally, those stains are described without any differentiation as ‘fox-spots’. The examination of various paintings concerned led to the conclusion, that there exist different kinds of stains that need to be discriminated against each other, to ensure an appropriate conservation and restoration treatment. "This paper aims to characterize and differentiate the stains, and will provide preventive and practical treatment proposals for the conservation and restoration of affected paintings. Questions such as ‘What are the stains composed of?’ and ‘Which may be the causes?’ will be addressed. Stains may consist of a variety of contents, such as: Ligneous residues, fungal infestation, bacterial activity, a combination of microbial and support induced discolouration [SID], a ‘symbiotic relation’ of ‘SID’ and fungal infestation, or the blooming of ingredients from the original painting materials. A range of microscopic analysis of the actual microbiological infestation of selected samples will be provided. The paintings that were examined, sampled and treated, are part of the Puerto Rican heritage, and were all kept in excessive humid tropical conditions, before they entered the Conservation Department of the Museum of Contemporary Art in Puerto Rico. "Conservation treatment options of stained paintings on hardboard will be discussed. A high level of acidity (caused from SID and/or micro-organisms) may require measures of reduction, disinfection and neutralization. Treatment methods that reduce the ligneous stains and residues of micro-organisms, and neutralize affected areas in painting layers include stain removal through the application of soaking compresses (poultices), and de-acidification through alkaline material. "Other aspects of deterioration, that do not have to do directly with the formation of stains, but also are typical for hardboard as painting support, will be mentioned briefly." - U.R.