Coatings applied on damp building substrates: performance and influence on moisture transport

  • Vânia Brito
  • Teresa Diaz Gonçalves
  • Paulina Faria
Article

Abstract

Dampness is a common condition in old buildings and, accordingly, many paint systems specific for this type of building allow for application on walls with nonnegligible moisture content. In spite of that, performance evaluation of these paints is normally carried out using dry substrates or even on free paint films. This article presents research performed on 16 commercial paint systems: seven silicate, three silicone, three hydro-pliolite and two lime-based systems, as well as one common vinyl emulsion paint that served as reference. Each paint was applied and cured both on dry and on damp mortar substrates. The test specimens were subjected to water vapor permeability tests and evaporative drying tests. The following conclusions could be drawn: (i) the way paint systems influence the drying of the substrate, to which they were applied and where they cured, may vary significantly depending on the moisture content of that substrate; (ii) vapor permeability, measured with specimens applied and cured on dry substrate, may be an acceptable way of predicting a paint’s influence on drying, provided that the paints are applied and cured on dry substrate or that their characteristics are not significantly affected by the moisture content of that substrate.

Keywords

Paint system Old building Damp substrate Drying Moisture transport 

Notes

Acknowledgments

We are extremely thankful to Elena Charola and José Delgado Rodrigues for discussing the manuscript of the article. We would also like to thank the nine companies that supplied the paint systems used in this research. Finally, we acknowledge and thank the help, in carrying out the experimental work, of LNEC technicians José Costa, João Júnior and João Ribeiro.

References

  1. 1.
    CEN, Paints and Varnishes. Coating Materials and Coating Systems for Exterior Masonry and Concrete. Part 1: Classification. EN 1062-1:2004Google Scholar
  2. 2.
    Hall, C, Hoff, WD, Water Transport in Brick, Stone and Concrete. Spon Press, London and New York, 2002CrossRefGoogle Scholar
  3. 3.
    Freitas, V, “Influence of the Vapour Permeability of Paintings and the Higroscopicity of the Internal Coating on the Hygrothermal Behaviour of Walls.” Proceedings of the CIB-W40 Meeting, Kyoto, Japan, pp. 256–269, October 7–10, 1997Google Scholar
  4. 4.
    Massari, G, Massari, I, Damp Buildings: Old and New. ICCROM, Rome, 1993Google Scholar
  5. 5.
    I’Anson, SJ, Hoff, WD, “Water Movement in Porous Building Materials–VIII. Effects of Evaporative Drying on Height of Capillary Rise Equilibrium in Walls.” Build. Environ., 21 (3–4) 195–200 (1984)Google Scholar
  6. 6.
    Gonçalves, TD, Pel, L, Rodrigues, JD, “Influence of Paints on Drying and Salt Distribution Processes in Porous Building Materials.” Constr. Build. Mater., 23 (5) 1751–1759 (2008)CrossRefGoogle Scholar
  7. 7.
    Defreece, E, Sherry, N, Charola, AE, “Coatings on Brick Masonry: Are They Protective or Can They Enhance Deterioration?” JAIC, 46 39–52 (2007)Google Scholar
  8. 8.
    Brito, V, “Influence of Wall Paints on Drying of the Substrate.” MSc Thesis (in Portuguese). http://www-ext.lnec.pt/LNEC/bibliografia/DM/Dissertacao_Vania_Brito.pdf. LNEC and Universidade Nova de Lisboa, Lisbon (2009)
  9. 9.
    Hern, C, Snethlage, R, “Water Vapour Permeability of Painted Stone.” Proceedings of the 7th International Congress on Deterioration and Conservation of Stone, LNEC, Lisbon, pp. 677–686, June 15–18, 1992Google Scholar
  10. 10.
    ISO, Paints and Varnishes—Determination of Water-Vapour Transmission Properties. Cup Method. ISO/DIS 7783 (2008)Google Scholar
  11. 11.
    RILEM TC 25-PEM, Test No. II.2, “Coefficient of Water Vapour Conductivity. Recommended Tests to Measure the Deterioration of Stone and to Assess the Effectiveness of Treatment Methods.” Mater. Struct., 13 197–199 (1980)Google Scholar
  12. 12.
    RILEM TC 25-PEM, Test No. II.5, “Evaporation Curve. Recommended Tests to Measure the Deterioration of Stone and to Assess the Effectiveness of Treatment Methods.” Mater. Struct., 13 204–207 (1980)Google Scholar
  13. 13.
    Stoye, D, Freitag, W (eds.), Paints, Coatings and Solvents. Wiley-VCH, Weinheim, 1998Google Scholar
  14. 14.
    Müller, B, Poth, U, Coatings Formulation: An International Textbook. Vincentz, Hannover, 2006Google Scholar
  15. 15.
    Wacker Silicones, “Silicone Resin Emulsion Paints for Facades Multiple Protection for a Long-Lasting Effect.” http://www.wacker.com/cms/media/publications/downloads/SREP_023_EN.pdf. Retrieved March 2009
  16. 16.
    Eliokem, “At Each Site the Solution” (in French). http://www.pliolite.com (2009)
  17. 17.
    Leitão, LA, Elementary Course on Construction (in Portuguese). Imprensa Nacional, Lisbon, 1896Google Scholar
  18. 18.
    Margalha, G, “The Use of Lime in Mortars in the Alentejo.” MSc Thesis (in Portuguese). Universidade de Évora, Évora (1997)Google Scholar
  19. 19.
    CEN, Methods of Testing Cement. Part 1: Determination of Strength. EN 196-1:2005Google Scholar
  20. 20.
    CEN, Methods of Test for Mortar for Masonry—Part 2: Bulk Sampling of Mortars and Preparation of Test Mortars. EN 1015-2:1998Google Scholar
  21. 21.
    CEN, Methods of Test for Mortar for Masonry—Part 2: Bulk Sampling of Mortars and Preparation of Test Mortars. EN 1015-2:1998/A1:2006Google Scholar
  22. 22.
    CEN, Methods of Test for Mortar for Masonry. Part 3: Determination of Consistence of Fresh Mortar (By Flow Table). EN 1015-3:1999Google Scholar
  23. 23.
    CEN, Methods of Test for Mortar for Masonry. Part 3: Determination of Consistence of Fresh Mortar (By Flow Table). EN 1015-3:1999/A1:2004Google Scholar
  24. 24.
    CEN, Methods of Test for Mortar for Masonry. Part 3: Determination of Consistence of Fresh Mortar (By Flow Table). EN 1015-3:1999/A2:2006Google Scholar
  25. 25.
    CEN, Methods of Test for Mortar for Masonry. Part 6: Determination of Bulk Density of Fresh Mortar. EN 1015-6:1998Google Scholar
  26. 26.
    CEN, Methods of Test for Mortar for Masonry. Part 6: Determination of Bulk Density of Fresh Mortar. EN 1015-6:1998/A1:2006Google Scholar
  27. 27.
    Teutonico, JM, A Laboratory Manual for Architectural Conservators. ICCROM, Rome, 1988Google Scholar
  28. 28.
    RILEM TC 25-PEM, Test No. II.6, “Water Absorption Coefficient (Capillarity). Recommended Tests to Measure the Deterioration of Stone and to Assess the Effectiveness of Treatment Methods.” Mater. Struct., 13 209–210 (1980)Google Scholar
  29. 29.
    Gonçalves, TD, Rodrigues, JD, Abreu, MM, Esteves, AM, Santos Silva, A, “Causes of Salt Decay and Repair of Plasters and Renders of Five Historic Buildings in Portugal.” Proceedings of the Conference Heritage, Weathering and Conservation, CSIC, Instituto de Geologia Económica, Madrid, Vol. 1, pp. 273–284, June 21–24, 2006Google Scholar
  30. 30.
    CEN, Hygrothermal Performance of Building Materials and Products. Determination of Water Vapour Transmission Properties. EN ISO 12572:2001Google Scholar
  31. 31.
    Sherwood, TK, “The Drying of Solids II.” Ind. Eng. Chem., 21 (10) 976–980 (1929)CrossRefGoogle Scholar
  32. 32.
    Hall, C, Hoff, WD, Nixon, MR, “Water Movement in Porous Building Materials—VI. Evaporation and Drying in Brick and Block Materials.” Build. Environ., 19 (1) 13–20 (1984)CrossRefGoogle Scholar
  33. 33.
    Scherer, GW, “Theory of Drying.” J. Am. Ceram. Soc., 73 3–14 (1990)CrossRefGoogle Scholar
  34. 34.
    Commissione Normal, Misura dell’indice di asciugamento (drying index). CNR/ICR, Normal 29/88, Roma (1991)Google Scholar
  35. 35.
    Gossens, E, Van der Spoel, W, Bancken, E, “Moisture Transport in Coated Plaster.” Heron, 46 (3) 217–222 (2001)Google Scholar
  36. 36.
    Tavares, M, “Conservation and Restoration of External Renderings of Old Buildings. A Methodology of Study and Repair.” PhD Thesis (in Portuguese). FA/UTL (2009)Google Scholar
  37. 37.
    Almeida, S, Souza, L, “Real State Acrylic Paints for Historic Constructions” (in Portuguese). http://www.restaurabr.org/arc/arc06pdf/11_SandraAlmeida.pdf. Rev. Bras. Arqueom. Restaur. Conserv., 1 (6) 347–348 (2007)Google Scholar
  38. 38.
    Freitas, VP, Abrantes, V, Crausse, P, “Moisture Migration in Building Walls. Analysis of the Interface Phenomena.” Build. Environ., 31 (2) 99–108 (1996)CrossRefGoogle Scholar

Copyright information

© ACA and OCCA 2011

Authors and Affiliations

  • Vânia Brito
    • 1
  • Teresa Diaz Gonçalves
    • 1
  • Paulina Faria
    • 2
  1. 1.National Laboratory for Civil EngineeringLisbonPortugal
  2. 2.Polytechnic Institute of SetubalLavradioPortugal

Personalised recommendations