External wall insulation systems can effectively reduce energy consumption and carbon emissions during the operation phase of buildings. The design of waterproofing and moisture-proofing during the design phase is essential to ensure the durability and energy efficiency of building external wall insulation systems. Current mandatory general codes outline separate design methodologies for waterproofing (against liquid water) and moisture-proofing (against water vapor). Nevertheless, there exists a certain difference in objectives and control directions of these methodologies. To facilitate coordinated design and control of both waterproofing and moisture-proofing in external wall insulation systems, this study investigates moisture-proofing approaches grounded in energy efficiency criteria while maintaining effective waterproofing. The study outlines the primary requirements for moisture-proofing and waterproofing design in external wall insulation systems as stipulated in current key standards. It applies four exterior wall moisture resistance evaluation methods, including inner surface condensation, internal condensation, moisture accumulation and drying characteristics, to calculate and analyze the water vapor permeation resistance of waterproof layers in external insulation engineering. Furthermore, the study proposes moisture-proofing recommendations for waterproof layers, thereby establishing a technical foundation for the coordinated design of waterproofing and moisture-proofing in external wall insulation system.
HENSH S. Building physics-heat, air and moisture: fundamentals and engineering methods with examples and exercises[M]. England: John Wiley & Sons, 2017.
[2]
BAZLIM, HEITZMANNM, VILLACORTA HERNANDEZB. Durability of fibre-reinforced polymer-wood composite members: An overview[J]. Composite Structures, 2022, 295: 115827.
[3]
FENGC, ROELSS, JANSSENH. Towards a more representative assessment of frost damage to porous building materials[J]. Build Environ, 2019, 164: 106343.
SUNLixin, YANZengfeng, ZHOUHui. Research on system bonding strength of stone wool ETICS under the impact of long-term HAM effect[J]. Architecture & Culture, 2017 (6): 124-125.
[6]
SILVAC, BRANCOJ M, CAMõESA, et al. Dimensional variation of three softwood due to hygroscopic behavior[J]. Construction and Building Materials, 2014, 59: 25-31.
[7]
YANB, ZHANGW, YIW. Multi-scale study on the mechanical properties of concrete based on crack propagation under hygrothermal coupling[J]. Journal of Building Engineering, 2024, 91: 109680.
[8]
ZHOUZ, XUEQ. Investigation of cracking behavior of fine-grained clays exposed to different humidity environments and engineering implications based on X-ray computed tomography[J]. Construction and Building Materials, 2024, 450: 138643.
SHIYing, SUNLixin, JIANGZhaocai. Safety and key construction layer design of external thermal insulation system under hygrothermal performance[J]. Journal of BEE, 2022, 50(4): 15-19.
[11]
RIMAA, ABAHRIK, BENNAIF, et al. Microscopic estimation of swelling and shrinkage of hemp concrete in response to relative humidity variations[J]. Journal of Building Engineering, 2021, 43: 102929.
ZHANGYue, WANGChengaonan, WANGYansong. Study on thermal-humidity environment characteristics and disease relevance of Huayang rock and Yinxian rock in Wudang mountains[J]. Xi'an Univ. of Arch. & Tech. (Natural Science Edition), 2024, 56(6): 808-818.
[14]
BAHRAQA A, OBOTI B, AL-OSTAM A, et al. Molecular-level investigation on the effect of surface moisture on the bonding behavior of cement-epoxy interface[J]. Journal of Building Engineering, 2022, 61: 105299.
LUODaiwei, LIUJiaping. The influence of thermal and moisture property parameters of masonry structure materials on thermal calculation in hot and humid climate[J].J. Xi'an Univ. of Arch. & Tech. (Natural Science Edition), 2022, 54(6): 930-939.
[17]
JINH Q, YAOX L, FANL W, et al. Experimental determination and fractal modeling of the effective thermal conductivity of autoclaved aerated concrete: Effects of moisture content[J]. International Journal of Heat and Mass Transfer, 2016, 92: 589-602.
[18]
KHOUKHIM. The combined effect of heat and moisture transfer dependent thermal conductivity of polystyrene insulation material: Impact on building energy performance[J]. Energy and Buildings, 2018, 169: 228-235.
[19]
LAIQ, FUT, HUANGD, et al. Mold severity and fungal communities in university dormitories: The role of building characteristics and living habits[J]. Build Environ, 2025, 280: 113176.
[20]
LOTZW A. Moisture problems in buildings in hot humid climates[J]. ASHRAE Journal, 1989, 31(4): 26-27.
[21]
AYERSTG. The effects of moisture and temperature on growth and spore germination in some fungi[J]. Journal of Stored Products Research, 1969, 5(2): 127-141.
[22]
GLASERH. Graphical method for investigation of diffusional processes[J]. Kaltetechnik, 1959, 11: 345-349.
[23]
PHILIPJ, DE VRIESD. Moisture movement in porous materials under temperature gradients[J]. Eos, Transactions American Geophysical Union, 1957, 38(2): 222-232.
[24]
LUIKOVA V. Heat and Mass Transfer in Capillary-Porous Bodies[M]. Advances in Heat Transfer. Amsterdam:Elsevier, 1964: 123-184.
[25]
SHENX, LIL, CUIW, et al. Coupled heat and moisture transfer in building material with freezing and thawing process[J]. Journal of Building Engineering, 2018, 20: 609-615.
WANGJiacai, CHENXiafei, ZHUYanhua, et al. Heat and moisture transfer characteristics of salt-containing autoclaved aerated concrete under extreme heat and humidity climate[J]. Journal of BEE, 2024, 52(6): 104-108.
ZHOUMengli, FANGJinzhong, CHENXianghui, et al. Simulation study on the influence of reduced air pressure on vapor permeability coefficient and the hygrothermal performance of building exterior walls[J]. Building science, 2025, 41(2): 167-174.
[30]
MolendaC H A, CrausseP, LemarchandD. The influence of capillary hysteresis effects on the humidity and heat coupled transfer in a non-saturated porous medium[J]. International Journal of Heat and Mass Transfer, 1992, 35(6): 1385-1396.
Ministry of Housing and Urban-Rural Development of the People's Republic of China. General code for building environment: GB 55016—2021 [S]. Beijing: China Architecture & Building Press, 2021.
Ministry of Housing and Urban-Rural Development of the People's Republic of China. General code for waterproofing of building and municipal engineering: GB 55030—2022 [S]. Beijing: China Architecture & Building Press, 2022.
[35]
张勇. 全文强制防水通用规范引领行业技术发展[J]. 中国建筑防水, 2023 (1): 1-5.
[36]
ZHANGYong. Technical development driven by mandatory general code for waterproofing[J]. China Building Waterproofing, 2023 (1): 1-5.
Ministry of Housing and Urban-Rural Development of the People's Republic of China. Code for thermal design of civil building: GB 50176—2016 [S]. Beijing: China Architecture & Building Press, 2016.
Ministry of Housing and Urban-Rural Development of the People's Republic of China. Technical standard for engineering of external thermal insulation composite system based on rock wool: JGJ/T 480—2019 [S]. Beijing: China Architecture & Building Press, 2019.
Ministry of Housing and Urban-Rural Development of the People's Republic of China. Technical specification for waterproofing of exterior wall of building: JGJ/T 235—2011 [S]. Beijing: China Architecture & Building Press, 2011.
[43]
International Standardization Organization. Hygrothermal performance of building components and building elements -Internal surface temperature to avoid critical surface humidity and interstitial condensation-Calculation methods: ISO 13788: 2012 [S]. Switzerland: International Standardization Organization, 2012.
[44]
European Committee for Standardization. Hygrothermal performance of building components and building elements. Assessment of moisture transfer by numerical simulation: EN 15026: 2023 [S]. Belgium: European Committee for Standardization, 2023.
[45]
ASTM. Criteria for Moisture-Control Design Analysis in Buildings: A SHRAE 160-2021 [S]. USA: ASTM International, 2021.