Document RabLgY7GKO4OVygRX0vBd9ZVv

10 Thermal Test Coefficients ofAluminum Insulation for Buildings, by G. B. Wilkes,' F. G. Hechler and E. R. Queer (A.S.H.V.E. Transactions, Vol. 46, 1940, p. 109). fj* 11 Effect of Studs and Joists on Heat Flow Through Frame Walls and Ceilings, by g Paul D. Close (Heating, Piping and Air Conditioning, October, 1943, p. 529). 11 A.S.H.V.E. Research Report No. 1213--Heat Loss Through Basement Walls and Floors, by.F, C. Houghten, S. I. Taimuty, Carl Gutberlet and C. J. Brown ' (A.S.H.V.E. Transactions, Vol. 48, 1942, p. 369). ** Measurements of Heat Losses from Slab Floors, by R. S. Dill, Wm. C. Robinson and H. E. Robinson (National Bureau of Standards, Building Materials and Structures Report BMS 1(H). 14 See pp. 130-132 of Reference 7. 11 Heat Transmission through Glass, by G. V. Parmelee (A.S.H.V.E. Research Bulletin No. 1, July 1947). bibliography A.S.NHo..V.E85.2--ReEsffeeacrtschofRAeiproVretslo:cities on Surface Coefficients, by F. B. Rowley, A. B. Algren and J. L, Blackshaw (A.S.H.V.E. Transactions, Vol. 36,1930, p. 123). No. 895--Wind Velocity Gradients Near a Surface and Their Effect on Film Conductance, by F. C. Houghten and Paul McDermott (A.S.H.V.E. Transactions, Vol. 37, 1931, i>. 301). No. 914--Surface Coefficients as Affected by Direction of Wind, by F. B. Rowley and W. A. Eckley (A.S.H.V.E. Transactions, Vol; 38,1932, p. 33). No. 915--Conductivity of Concrete, by F. C. Houghten and Carl Gutberlet (A.S.H.V.E. Transac-'. No. 954--tTihoensH, eVaoti.C3o8,nd19u3c2t,ivpi.ty47o).f Wood at Climatic Temperature Differences, by F. B. Rowley ` (A.S.H.V.E. Transactions, Vol. 39, 1933, p. 329). No. 996--Insulating Value of Bright Metallic Surfaces, by F. B. Rowley (A.S.H.V.E. Transactions, No. 1026--VThoel.r4m0a, l1P93r4o,ppe.rt4ie1s3)o. f Concrete Construction, by F. B. Rowley, A. B. Algren and Clifford- Carlson (A.S.H.V.E. Transactions, Vol. 42,1936, p. 33). No. 1048--Thermal Properties of Concrete Construction, by F. B. Rowley, A. B. Algren and Robert Lander (A.S.H.V.E. Transactions, Vol. 43, 1937, p. 33). No. 1351--Overall Coefficients for Flat Glass Determined under Natural Weather Conditions, by G. VS , Parmelee.and W. W. Aubele (A.S.H.V.E. Transactions, Vol. 55, 1949, p. 39). Radiation and Convection Across Air Spaces in Frame Construction, by G. B. Wilkes and C. M. F. Peter sonIn(Asu.Sla.Htin.Vg.EE.ffTecrtanosfaScutciocnesss, iVveolA. 4ir3, S1p9a37c,epB. o35u1n).ded;by-Bright Metallic Surfaces, by L. W. Sehad (A.STh.He.rVm.aEl.CTornadnusacctivtiiotynos,f VWoolo. d3,7b,1y93J1., Dp.. 2M8a5)c.Lean (A.S.H.V.E. Transactions, Vol. 47,.1941, p. 32S).The Specific Heat of Thermal Insulating Materials, by G. B. Wilkes and C. O. Wood (A.S.H.V.E. Trans actiHoena'st, LVoossl. S4t8u,di1e9s42in, pF.o4u9r3I)d.entical Buildings to Determine the Effect of Insulation, by D. B. Anderson (A.SE.fHfe.cVt.Eof. CTerialinnsgaIcntsiuolnast,ioVnolu.p4o8n, 1S94u2m, pm.e4r7C1)o..mfort, by T. D. Phillips {National Bureau of Standard*, RepTohret rBmMaSl 5In2s, uJlualtyion1, M19a4d0e).of Wood-Base Materials, Its Application and Use in Houses, by L. V. Teesdik (U. S. Forest Products Laboratory Report No. R1740, October 1949). T Heat Transmission Through Building Materials, by F. B. Rowley and A- B. Algren {University of Minne sota, Engineering Experiment Station Bulletin No. 8). Building Insulation, by P. D. Close (American Technical Society, Chicago, 1945). . 4 IT 7 ,A T .a CHAPTER 10 MOISTURE IN BUILDING CONSTRUCTION Properties of Water in Air; Water in Building Materials; Movement of Moisture in Materials; Vapor Transmission; Permeance and Testing; Visible Condensation; Concealed Condensation in Heated Buildings; Control of Concealed Condensation; Condensation in Cooled Structures . THE behavior of moisture is too often overlooked or given scant at tention in the design and construction of buildings. It is present as a vapor in all air and as adsorbed moisture in most building materials. may be present also at times in the free liquid state or as ice, in the solid state, within the range of temperatures encountered in many buildings. Problems involving moisture may arise from changes in moisture content, from the presence of excessive moisture, or from effects associated with its changes in state. Of particular interest here is the change from the vapor to the liquid or solid state, known as condensation. This may be associated with a re duction of temperature with time, or may occur as a result of migration of water vapor to regions of lower temperature. Moisture problems involv ing condensation are therefore most likely to occur in buildings in any climate in which there is a source of water vapor at temperatures above normal, or in cooled structures, and in buildings in cold climates. Moisture problems in residences occur in winter and become increasingly important as homes are built smaller and tighter. Water vapor originates from such necessary living requirements as cooking, laundering, bathing, and the breathing and perspiration of people. In a typical family of four, the average daily production of water vapor from these sources may be as much as 25 lb, and may be much greater where such appliances as humidifiers, automatic washers, and dryers are used.1 Another large source of water vapor is sometimes the bare earth in a crawl space or basement. All this water vapor must escape from the dwelling. It PROPERTIES OF WATER VAPOR IN AIR Water vapor in air is a gas which occupies all the space, along with the air Present. In many ways, the water vapor can act independently of the a!r> since in general its properties do not depend on the presence of the a!r- It exerts its own vapor pressure, and can move about through air in a space, or move through materials under differences in its own vapor swufUre' independently of the air. However, when the air is moved suddenly or is heated or cooled, the water vapor present is similarly ected, so that it is usually necessary to consider it as a part of an airvaPor mixture. kn^16 ProPert*es of mixtures of air and water vapor are relatively well in tlT1 an<^ are dealt with fully in Chapter 3, Thermodynamics. Changes the vj6 ProPert'ies w'th heating and cooling can be followed readily with a!<4 of a psychrometric chart, shown in outline in Fig. 1. The satura te