MOISTURE-TECHNOLOGICAL INVESTIGATIONS IN CONNECTION WITH PAINTS ON EXTERNAL RENDERINGS

VALUES FOR THE WATER VAPOR PERMEABILITY ARE OBTAINED FOR COMMERCIAL EMULSION PAINTS BY TAKING ACCOUNT OF THE USUAL PAINT THICKNESSES (APPROX. 0.15 MM), WHICH ARE OF THE ORDER OF MAGNITUDE OF 2CM THICK EXTERNAL RENDERINGS. CLOSED PAINT FILMS OF EMULSION PAINTS HAVE A RELATIVELY HIGH WATER- REPELLENT ACTION. UNDER EXTREME EXPOSURE CONDITIONS (EXPOSED SIDES OF BUILDINGS), HOWEVER, THE WATER-REPELLENT ACTION OF THE COATINGS DIMINISHES, THIS BEING DUE TO FLAWS IN THE PAINT FILM WHICH BECOME LARGER IN COURSE OF TIME, AND ALSO TO THE FORMATION OF FINE CRACKS IN THE PAINT WHICH MAY GIVE RISE TO DETACHMENT OF THE FILM FROM ITS BASE. EMULSION PAINTS SIGNIFICANTLY HINDER THE HARDENING OF PURE WHITE LIME RENDERINGS. WHEN SUCH PAINTS ARE USED, ONE SHOULD MADE IT A RULE TO EMPLOY RENDERING MORTARS CONTAINING A PROPORTION OF HYDRAULICALLY HARDENING BINDING AGENT (HYDRAULIC OR EMINENTLY HYDRAULIC LIME MORTAR, LIME-CEMENT MORTAR, WHITE LIME MORTAR WITH ADDED CEMENT). BECAUSE OF THE DIFFUSION-INHIBITING ACTION OF EMULSION PAINTS, A CERTAIN ACCUMULATION OF MOISTURE MAY OCCUR IN THE EXTERNAL WALLS OF RESIDENTIAL BUILDINGS IN THE COURSE OF A WINTER. WITH THE USUAL KINDS OF WALL CONSTRUCTION AND UNDER AVERAGE CONDITIONS THE MOISTURE ACCUMULATIONS THAT CAN BE EXPECTED TO OCCUR ARE, HOWEVER, NOT SO GREAT THAT THEY CAN BE REGARDED AS A CAUSE OF DAMAGE TO THE PAINTWORK OR RENDERING. DAMAGE TO THE PAINTWORK IS, INSTEAD, DUE TO THE ACTION OF MOISTURE WHICH HAS PENETRATED FROM OUTSIDE THROUGH DEFECTIVE AREAS IN THE PAINT COATING.

• Supplemental Notes:
  • Vol 19, No 1, PP 17-29
• Authors:
  • Kunzel, H
• Publication Date: 1966-1

Media Info

• Serial:
  • Zement-Kalk-Gips

Subject/Index Terms

• TRT Terms: Calcium oxide; Concrete hardening; Cracking; Emulsions; Hardness; Lime cement; Mortar; Paint; Permeability; Thickness; Water repellents; Water vapor
• Old TRIS Terms: Commercial
• Subject Areas: Geotechnology; Highways; Materials;

Filing Info

• Accession Number: 00216225
• Record Type: Publication
• Files: TRIS
• Created Date: Feb 20 1994 12:00AM