There are three basic methods walls control water intrusion: moisture storage, drained cladding, or face-sealed cladding.Committee on Damp Indoor Spaces and Health, Board on Health Promotion and Disease Prevention. Damp indoor spaces and health. Institute of Medicine, (U. S.). National Academies Press. Washington, D. C.. 2004. 34-35. Print. Moisture storage is typical of stone and brick mass-wall buildings where moisture is absorbed and released by the walls of the structure itself. Drained cladding also known as screened wallsStraube, J. F.and Burnett, E. F. P., "Driving Rain and Masonry Veneer". Water Leakage through Building Facades, ASTM STP 1314. R. J. Kudder and J. L. Erdly, Eds. American Society for Testing and Materials (ASTM), 1998. 75. Print. acknowledges moisture will penetrate the cladding so a moisture barrier such as housewrap or felt paper inside the cladding provides a second line of defense and sometimes a drainage plane or air gap allows a path for the moisture to drain down through and exit the wall. Sometimes ventilation is provided in addition to the drainage plane such as in rainscreen construction. Face-sealed also called barrier wall or perfect barrier cladding relies on maintaining a leak-free surface of the cladding. Examples of face sealed cladding are the early exterior insulation finishing systems, structural glazing, metal clad panels, and corrugated metal.
TheRE ArE ThrEe basIc meTHODS walls ContROl waTEr inTRusIOn: MoiSTure stORage, drainEd cLaddInG, or faCe-seALEd ClAddiNg.coMmITtee oN damp InDoor sPaCeS ANd Health, bOard on hEAltH PRomoTion and diSease preVeNtIOn. DAmp inDoor SpacES anD hEALTh. instItutE OF medIcine, (u. S.). NaTIOnal ACademies presS. Washington, D. c.. 2004. 34-35. print. MoIsture stOragE is TypicAL OF stone And bRick masS-wAll buildIngs WhEre MoIStUre is absoRBed anD releaSed bY the walLs oF the sTRucTURe ITSeLF. draiNeD claddiNG AlsO kNown aS scrEeNED walLSStraUbe, j. f.and burnett, e. f. p., "driviNG rAin and mASoNry veneEr". watEr leAKage tHrOuGh buIlding fAcAdes, astm sTp 1314. r. j. kuddeR aND j. L. erdLy, eds. amErICan soCIETy for Testing aNd maTeRiaLs (astM), 1998. 75. PRINT. AcknOwledGeS moiStuRE wIll peneTrAte tHE clADdinG SO A moIStuRe baRrier SuCH As hoUsEwraP or feLT PaPER inSIde the cLadDInG ProvIdes a SecOnd lIne Of defEnse And sometImes a DrAInaGE pLAne or AIr gaP AllOws a pAth fOr the moIsture To DraiN Down ThrouGh anD exIt The wall. soMeTiMes ventilaTiON is prOvIdeD iN aDdItION To The dRainaGe plane suCh as in rAinsCREEN coNsTRucTiOn. face-sEAled also cAlleD bArRiEr walL or pErfEcT BaRrIer cladding RelIes on MaiNtaining a lEak-frEe surface of The claDDing. eXAmpleS of face sealed ClADDING are tHe eArLy extERIor iNsuLatIoN fiNiShiNG systemS, struCTUral GlAziNg, mEtal claD panels, and corRuGaTed Metal.