Monitoring the Damage of Exterior Renders Caused by the Environment

Monitoring the Damage of Exterior Renders Caused by the Environment

Monika Čáchová Jaroslava Koťátková Dana Koňáková Eva Vejmelková Martin Keppert Pavel Reiterman Jaromír Žumár Robert Černý

Department of Materials Engineering and Chemistry, Faculty of Civil Engineering, Czech Technical University in Prague, Czech Republic

Experimental Center, Faculty of Civil Engineering, Czech Technical University in Prague, Czech Republic

1 February 2017
| Citation



Three renders commonly used in the Czech Republic on the exterior side of building envelopes are exposed for 2 years to the environmental conditions of the city of Prague. The effect of external environment on their possible damage is monitored using the measurement of a variety of material properties in selected time intervals. The experimental results do not show any significant deterioration of most parameters during the 2-year investigation period. The open porosity is found to decrease with time due to the continuing hardening processes. The mechanical properties are thus improved after 1 year of exposition and only little worsened after the second year. The changes in the pore structure also result in deceleration of water- and water-vapor transport and a slight increase of thermal conductivity. The obtained results will serve as reference data for finding a correlation between the accelerated laboratory tests and the behavior of analyzed materials in real building structures.


basic physical properties, environmental effects, exterior plasters, liquid water transport, strength, thermal properties, water vapor transport


[1] Rovnaníková, P., Omítky, Chemické a technologické vlastnosti. STOP, Praha, 2002.

[2] Cabrera, J. & Rojas, M.F., Mechanism of hydration of the metakaolin–lime–water system. Cement and Concrete Research, 31, pp. 177–182, 2001.

[3] Shvarzman, A., Kovler, K., Grader, G.S. & Shter, G.E., The effect of dehydroxylation/amorphization degree on pozzolanic activity of kaolinite. Cement and Concrete Research, 33, pp. 405–416, 2003.

[4] Černý, R., Kunca, A., Tydlitát, V., Drchalová, J. & Rovnaníková, P., Effect of pozzolanic admixtures on mechanical, thermal and hygric properties of lime plasters. Construction and Building Materials, 20, pp. 849–857, 2006.

[5] Pernicová, R., Pavlíková, M. & Černý, R., Effect of metakaolin on chloride binding in lime-based composites. Proceedings of Computational Methods and Experimental Measurements XIII, pp. 357–365, 2007.

[6] Pavlík, Z., Vejmelková, E., Fiala, L. & Černý, R., Effect of moisture on thermal conductivity of lime-based composites. International Journal of Thermophysics, 30, pp. 1999–2014, 2009.

[7] Kočí, J., Maděra, J., Rovnaníková, P. & Černý, R., Hygrothermal performance of innovative renovation renders used for different types of historical masonry. WIT Transactions on the Built Environment, 118, pp. 683–693, 2011.

[8] Kočí, V., Maděra, J. & Černý, R., Exterior thermal insulation systems for AAC building envelopes: computational analysis aimed at increasing service life. Energy & Buildings, 47, pp. 84–90, 2012.

[9] Pavlíková, M., Pavlík, Z., Keppert, M. & Černý, R., Salt transport and storage parameters of renovation plasters and their possible effects on restored buildings’ walls. Construction and Building Materials, 25, pp. 1205–1212, 2011.

[10] Park, S., Kwon, S. & Jung, S.H., Analysis technique for chloride penetration in cracked concrete using equivalent diffusion and permeation. Construction and Building Materials, 29, pp. 183–192, 2012.

[11] Lanzón, M. & García-Ruiz, P.A., Evaluation of capillary water absorption in rendering mortars made with powdered waterproofing additives. Construction and Building Materials, 23, pp. 3287–3291, 2009.

[12] Izaguirre, A., Lanas, J. & Álvarez, J.I., Effect of water-repellent admixtures on the behaviour of aerial lime-based mortars. Cement and Concrete Research, 39, pp. 1095– 1104, 2009.

[13] Tesárek, P., Rovnaníková, P., Kolísko, J. & Černý, R., Properties of hydrophobized FGD gypsum. Cement Wapno Beton, 10, pp. 255–264, 2005.

[14] ČSN EN 1015-3: Methods of test for mortar for masonry - Part 3: determination of consistence of fresh mortar (by flow table), Prague, 2007.

[15] ČSN EN 1015-10: Methods of test for mortar for masonry - Part 10: determination of dry bulk density of hardened mortar, Prague, 2000.

[16] ČSN EN 1015-11: Methods of test for mortar for masonry - Part 11: determination of flexural and compressive strength of hardened mortar, Prague, 2007.

[17] ČSN 72 2452: Testing of frost resistance of mortar, Prague, 2005.

[18] ČSN 1015-19: Methods of test for mortar for masonry - Part 19: determination of water vapour permeability of hardened rendering and plastering mortars, Prague, 2005.

[19] Kumaran, M.K., Moisture diffusivity of building materials from water absorption measurements. IEA annex 24 report T3-CA-94/01, Ottawa, 1994.

[20] ČSN EN 1015-18: Methods of test for mortar for masonry - Part 18: determination of water absorption coefficient due to capillarity action of hardened mortar, Prague, 2003.

[21] Roels, S., Carmeliet, J., Hens, H., Adan, O., Brocken, H., Černý, R., Pavlík, Z., Hall, C., Kumaran, K., Pel, L. & Plagge, R., Interlaboratory comparison of hygric properties of porous building materials. Journal of Thermal Envelope and Building Science, 27, pp. 307–325, 2004.

[22] Applied Precision – ISOMET, [User manual], Bratislava, 1999