360:, sometimes called a k-value or lambda-value (lowercase λ). The thermal conductivity (k-value) is the ability of a material to conduct heat; hence, the lower the k-value, the better the material is for insulation. Expanded polystyrene (EPS) has a k-value of around 0.033 W/mK. For comparison, phenolic foam insulation has a k-value of around 0.018 W/mK, while wood varies anywhere from 0.15 to 0.75 W/mK, and steel has a k-value of approximately 50.0 W/mK. These figures vary from product to product, so the UK and EU have established a 90/90 standard which means that 90% of the product will conform to the stated k-value with a 90% confidence level so long as the figure quoted is stated as the 90/90 lambda-value.
38:
27:
889:
288:. This comes at a price, however: R-values that include non-conductive processes may no longer be additive and may have significant temperature dependence. In particular, for a loose or porous material, the R-value per inch generally depends on the thickness, almost always so that it decreases with increasing thickness (
1131:
550:
practice to describe the thermal resistance of insulation products, layers, and most other parts of the building enclosure (walls, floors, roofs). Other areas of the world more commonly use U-value/U-factor for elements of the entire building enclosure including windows, doors, walls, roof, and ground slabs.
352:
is better at reducing heat transfer). It is expressed in watts per meter squared kelvin (W/m²K). This means that the higher the U-value the worse the thermal performance of the building envelope. A low U-value usually indicates high levels of insulation. They are useful as it is a way of predicting
343:
that describes how well a building element conducts heat or the rate of transfer of heat (in watts) through one square metre of a structure divided by the difference in temperature across the structure. The elements are commonly assemblies of many layers of components such as those that make up
549:
Note that the term "U-factor" (which redirects here) is usually used in the U.S. and Canada to express the heat flow through entire assemblies (such as roofs, walls, and windows). For example, energy codes such as ASHRAE 90.1 and the IECC prescribe U-values. However, R-value is widely used in
1173:
286:
65:
properties of the object. R-values are used in describing effectiveness of insulation and in analysis of heat flow across assemblies (such as walls, roofs, and windows) under steady-state conditions. Heat flow through an object is driven by temperature difference (e.g.
1243:
1097:
165:
per hour). Moreover, as long as the materials involved are dense solids in direct mutual contact, R-values are additive; for examle, the total R-value of an object composed of several layers of material is the sum of the R-values of the individual
301:
may be R-14 at -12° C (10° F) and R-12 at +43° C (110° F). Nevertheless, in construction it is common to treat R-values as independent of temperature. Note that an R-value never accounts for radiative or convective processes at the material's
789:
247:) significantly contribute to heat transfer within the material. In such cases, it is useful to introduce an ″apparent thermal conductivity″, which captures the effects of all three kinds of processes, and to define the R-value in general as
827:
758:
627:
Because the units are usually not explicitly stated, one must decide from context which units are being used. In this regard, it helps to keep in mind that I-P R-values are 5.68 times larger than the corresponding SI R-values.
453:
344:
walls/floors/roofs etc. It measures the rate of heat transfer through a building element over a given area under standardised conditions. The usual standard is at a temperature gradient of 24 °C (75.2 °F), at 50%
317:) of a material or assembly. The U.S. construction industry preferes to use R-values, however, because they are additive and because bigger values mean better insulation, neither of which is true for U-factors.
858:
296:
with thickness). For similar reasons, the R-value per inch also depends on the temperature of the material, usually increasing with decreasing temperature (polyso again being an exception); a nominally R-13
617:
R-values expressed in I-P units are approximately 5.68 times as large as R-values expressed in SI units. For example, a window that is R-2 in the I-P system is about RSI 0.35, since 2/5.68 ≈ 0.35.
600:
213:
983:
250:
197:
foam), or for an assembly of materials (e.g. a wall or a window). In the case of materials, it is often expressed in terms of R-value per unit length (e.g. per inch of thickness). The latter can be
1021:
1055:
201:
in the case of low-density building thermal insulations, for which R-values are not additive: their R-value per inch is not constant as the material gets thicker, but rather usually decreases.
228:″this window has an R-value of 2″; ″this is a window with R=2″ (and similarly with RSI-values, which also include the possibility ″this window provides RSI 0.35 of resistance to heat flow″).
698:
1274:
925:
33:
is an extremely good thermal insulator, which at a presure of one-tenth of an atmosphere has an R-value of R-20 per inch of thickness, compared to R-3.5/inch for a fiberglass blanket.
212:
is about 5.68 times larger than when expressed in SI units, so that, for example, a window that is R-2 in I-P units has an RSI of 0.35 (since 2/5.68=0.35). For R-values there is
1204:
1604:
1643:
494:
144:
104:
521:
1661:
621:
In countries where the SI system is generally in use, the R-values will also normally be given in SI units. This includes the U.K., Australia, and New
Zealand.
947:
American
Society of Heating, Refrigerating and Air-Conditioning Engineers (2013). "Heat, air, and moisture control in building assemblies—Fundamentals".
378:
729:
1618:
1587:
1503:
1187:
1111:
997:
963:
903:
872:
712:
1296:
1226:
1153:
1077:
208:) are usually not explicitly stated, and so it is important to decide from context which units are being used: an R-value expressed in
1257:
841:
803:
772:
1610:
1462:
1337:
1035:
281:{\displaystyle R={\frac {\scriptstyle {\text{thickness of the specimen}}}{\scriptstyle {\text{apparent thermal conductivity}}}}}
235:, the lower its R-value. On the other hand, the thicker the material, the higher its R-value. Sometimes heat transfer processes
604:
298:
217:
209:
42:
224:. As far as how R-values are reported, all of the following mean the same thing: ″this is an R-2 window″; ″this is an R2
989:
1533:
624:
I-P values are commonly given in the U.S. and Canada, though in Canada normally both I-P and RSI values are listed.
788:
Rabl, Ari; Curtiss, Peter (2005). "9.6 Principles of Load
Calculations". In Kreith, Frank; Goswami, D. Yogi (eds.).
731:
Faced fiberglass batt insulation can be stapled to the stud faces or slightly inset, but avoid compressing the batts
353:
the composite behavior of an entire building element rather than relying on the properties of individual materials.
1249:
757:
Ellis, Wayne (1988). "Appendix: Terminology update: Symbols mean specific terms". In
Strehlow, Richard Alan (ed.).
1439:
826:
Kośny, Jan; Yarbrough, David W. (2017). "4.10 Thermal
Bridges in Building Structures". In Chhabra, Ray P. (ed.).
340:
106:) between two sides of the object, and the R-value quantifies how effectively the object resists this drive:
1384:
1027:
1571:
American
Society of Heating, Refrigerating and Air-Conditioning Engineers (2013). "Units and Conversions".
37:
326:
310:
674:
1495:
1276:
A Handbook on Low-Energy
Buildings and District-Energy Systems: Fundamentals, Techniques and Examples
1206:
A Handbook on Low-Energy
Buildings and District-Energy Systems: Fundamentals, Techniques and Examples
1179:
1133:
A Handbook on Low-Energy
Buildings and District-Energy Systems: Fundamentals, Techniques and Examples
1103:
1057:
A Handbook on Low-Energy
Buildings and District-Energy Systems: Fundamentals, Techniques and Examples
895:
704:
592:
357:
314:
232:
205:
198:
162:
463:
1288:
1218:
1145:
1069:
1428:
764:
356:
In most countries the properties of specific materials (such as insulation) are indicated by the
244:
175:
109:
69:
62:
58:
1361:
1614:
1583:
1499:
1398:
1292:
1253:
1222:
1183:
1149:
1107:
1073:
1031:
993:
959:
899:
868:
837:
799:
768:
708:
584:
503:
289:
1574:
1411:
950:
61:
flow of heat: the greater the R-value, the greater the resistance, and so the better the
1657:
1635:
608:
221:
1548:
562:
194:
171:
50:
448:{\displaystyle U={\frac {1}{R}}={\frac {{\dot {Q}}_{A}}{\Delta T}}={\frac {k}{L}}}
580:
1519:
539:
240:
26:
17:
1284:
1280:
1214:
1210:
1141:
1137:
1065:
1061:
864:
833:
795:
542:
or Thermal Overall Grade (where 1 tog = 0.1 m·K/W), used for
497:
1125:
1123:
231:
The more a material is intrinsically able to conduct heat, as given by its
57:
is a measure of how well an object, per unit of its exposed area, resists
345:
1450:
30:
1313:
1579:
1175:
Heating, Cooling, Lighting: Sustainable Design Methods for Architects
1099:
Heating, Cooling, Lighting: Sustainable Design Methods for Architects
955:
700:
Heating, Cooling, Lighting: Sustainable Design Methods for Architects
565:
1049:
1047:
1490:
McQuiston, Faye C.; Parker, Jerald D.; Spitler, Jeffrey D. (2005).
1318:, The Polyisocyanurate Insulation Manufacturers Association (PIMA)
1312:
The Polyisocyanurate Insulation Manufacturers Association (PIMA),
760:
Standardization of Technical Terminology: Principles and Practices
543:
36:
25:
1424:
1091:
1089:
1638:
with the name "DOE" has been invoked, but is not defined in the
588:
569:
158:
1492:
Heating, Ventilating, and Air Conditioning: Analysis and Design
1451:
European phenolic foam association: Properties of phenolic foam
614:
Some sources use ″RSI″ when referring to R-values in SI units.
1167:
1165:
1606:
Scientific Unit Conversion: A Practical Guide to Metrication
187:
527:
is the material's coefficient of thermal conductivity and
370:
with SI units of W/(mK) and U.S. units of BTU/(hr °F ft);
306:, which may be an important factor for some applications.
676:
Aerogel Research at LBL: From the Lab to the Marketplace
1547:
Canada Mortgage and Housing Corporation (CMHC) (2018),
1463:"Indicators of Insulation Quality: U-value and R-value"
860:
Heating and Cooling of Buildings: Design for Efficiency
857:
Kreider, Jan F.; Curtiss, Peter S.; Rabl, Ari (2010).
269:
262:
1578:. Vol. Fundamentals (SI ed.). Atlanta, GA:
1339:
Big News: The R-Value of Insulation Is Not a Constant
1015:
1013:
1011:
1009:
954:. Vol. Fundamentals (SI ed.). Atlanta, GA:
506:
466:
381:
253:
112:
72:
153:by the surface area of the object's side gives the
523:is the tempreture difference across the material,
515:
488:
447:
280:
193:An R-value can be given for a material (e.g. for
138:
98:
752:
750:
748:
1553:, Canada Mortgage and Housing Corporation (CMHC)
1360:Building Science Corporation (23 January 2013),
292:(″polyso″) being an exception; its R-value/inch
8:
1023:A Dictionary of Weights, Measures, and Units
821:
819:
817:
815:
535:is referred to as unit surface conductance.
926:"The Promise of Energy-Efficient Buildings"
919:
917:
915:
863:(Revised Second ed.). Boca Raton, FL:
174:term for what is in other contexts called ″
977:
975:
155:total rate of heat flow through the object
45:insulation with its R-value visible (R-21)
611:, so the same I-P unit is used in both.
505:
480:
469:
468:
465:
435:
416:
405:
404:
401:
388:
380:
270:
263:
260:
252:
130:
117:
111:
90:
77:
71:
679:, Lawrence Berkeley National Laboratory
665:
554:Units: metric (SI) vs. inch-pound (I-P)
1407:
1396:
791:CRC Handbook of Mechanical Engineering
763:. Vol. Second. Philadelphia, PA:
576:whereas the I-P (inch-pound) unit is
894:(Illustrated ed.). Hoboken, NJ:
309:The R-value is the reciprocal of the
7:
930:Oak Ridge National Laboratory Review
558:The SI (metric) unit of R-value is
531:is its thickness. In some contexts,
1652:
1630:
1363:RR-0002: The Thermal Metric Project
1248:(2010 ed.). Washington, D.C.:
1242:International Code Council (2010).
982:Rathore, M. M.; Kapuno, R. (2011).
832:(Second ed.). Boca Raton, FL:
829:CRC Handbook of Thermal Engineering
794:(Second ed.). Boca Raton, FL:
1406:Cite has empty unknown parameter:
1245:Residential Code of New York State
507:
423:
24:
1520:"Efficient Windows Collaborative"
1336:Bailes, Allison (24 April 2013),
341:overall heat transfer coefficient
1385:"U-Value Measurement Case Study"
1611:Springer Science+Business Media
1609:(Second ed.). London, UK:
1494:(Sixth ed.). Hoboken, NJ:
924:Krause, Carolyn (Summer 1980).
1366:, Building Science Corporation
489:{\displaystyle {\dot {Q}}_{A}}
1:
1603:Cardarelli, François (1999).
1178:(4th ed.). Hoboken, NJ:
1102:(4th ed.). Hoboken, NJ:
990:Jones & Bartlett Learning
988:(2nd ed.). Sudbury, MA:
703:(4th ed.). Hoboken, NJ:
272:apparent thermal conductivity
204:The units of an R-value (see
170:Note that the R-value is the
1470:U-value and building physics
1273:Harvey, L. D. Danny (2006).
1203:Harvey, L. D. Danny (2006).
1130:Harvey, L. D. Danny (2006).
1054:Harvey, L. D. Danny (2006).
572:(m·K/W or, equally, m·°C/W),
734:, U.S. Department of Energy
728:U.S. Department of Energy,
139:{\displaystyle T_{2}-T_{1}}
99:{\displaystyle T_{2}-T_{1}}
1681:
1250:International Code Council
324:
239:than conduction (namely,
1172:Lechner, Norbert (2015).
1096:Lechner, Norbert (2015).
985:Engineering Heat Transfer
697:Lechner, Norbert (2015).
265:thickness of the specimen
190:(metric) units are used.
51:building and construction
1534:"Public Codes Cyberregs"
888:Chen, C. Julian (2011).
516:{\displaystyle \Delta T}
348:with no wind (a smaller
182:It is sometimes denoted
149:by the R-value and then
1425:P2000 Insulation System
1028:Oxford University Press
891:Physics of Solar Energy
1658:list-defined reference
1636:list-defined reference
1472:. greenTEG. 2016-03-17
1440:Polystyrene insulation
1020:Fenna, Donald (2002).
958:. pp. 25.5–25.6.
673:Kahn, Jeffery (1991),
599:For R-values there is
517:
490:
449:
282:
210:I-P (inch-pound) units
140:
100:
46:
34:
1660:has no name (see the
1550:Insulating Your House
518:
491:
450:
327:Thermal transmittance
311:thermal transmittance
283:
141:
101:
40:
29:
1289:Taylor & Francis
1219:Taylor & Francis
1146:Taylor & Francis
1106:. pp. 683–685.
1070:Taylor & Francis
593:British thermal unit
504:
464:
379:
358:thermal conductivity
251:
233:thermal conductivity
110:
70:
652:× 0.1761101838
1640:<references>
642:× 5.678263337
605:US customary units
513:
486:
445:
366:is the inverse of
278:
275:
268:
218:US customary units
176:thermal resistance
136:
96:
63:thermal insulating
47:
35:
1620:978-1-4471-0805-4
1589:978-1-936504-46-6
1505:978-0-471-47015-1
1342:, Energy Vanguard
1189:978-1-118-58242-8
1113:978-1-118-58242-8
999:978-0-7637-7752-4
965:978-1-936504-46-6
905:978-0-470-64780-6
874:978-1-4398-8250-4
714:978-1-118-58242-8
646:RSI-value (in SI)
640:RSI-value (in SI)
585:degree Fahrenheit
477:
443:
430:
413:
396:
276:
273:
266:
172:building industry
1672:
1667:
1666:
1665:
1649:
1648:
1647:
1641:
1625:
1624:
1600:
1594:
1593:
1582:. p. 38.1.
1568:
1562:
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1558:
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1381:
1375:
1374:
1373:
1371:
1357:
1351:
1350:
1349:
1347:
1333:
1327:
1326:
1325:
1323:
1315:LTTR/QualityMark
1309:
1303:
1302:
1298:978-184407-243-9
1287:, an imprint of
1283:, an imprint of
1270:
1264:
1263:
1239:
1233:
1232:
1228:978-184407-243-9
1217:, an imprint of
1213:, an imprint of
1200:
1194:
1193:
1169:
1160:
1159:
1155:978-184407-243-9
1144:, an imprint of
1140:, an imprint of
1127:
1118:
1117:
1093:
1084:
1083:
1079:978-184407-243-9
1068:, an imprint of
1064:, an imprint of
1051:
1042:
1041:
1017:
1004:
1003:
979:
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969:
944:
938:
937:
921:
910:
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885:
879:
878:
854:
848:
847:
823:
810:
809:
785:
779:
778:
754:
743:
742:
741:
739:
725:
719:
718:
694:
688:
687:
686:
684:
670:
650:R-value (in I-P)
636:R-value (in I-P)
631:More percisely,
522:
520:
519:
514:
495:
493:
492:
487:
485:
484:
479:
478:
470:
454:
452:
451:
446:
444:
436:
431:
429:
421:
420:
415:
414:
406:
402:
397:
389:
321:U-factor/U-value
290:polyisocyanurate
287:
285:
284:
279:
277:
274:
271:
267:
264:
261:
227:
181:
169:
157:(as measured in
145:
143:
142:
137:
135:
134:
122:
121:
105:
103:
102:
97:
95:
94:
82:
81:
41:Installed faced
1680:
1679:
1675:
1674:
1673:
1671:
1670:
1669:
1668:
1655:
1653:
1650:
1639:
1633:
1631:
1628:
1621:
1613:. p. 308.
1602:
1601:
1597:
1590:
1575:ASHRAE Handbook
1570:
1569:
1565:
1556:
1554:
1546:
1545:
1541:
1532:
1531:
1527:
1518:
1517:
1513:
1506:
1489:
1488:
1484:
1475:
1473:
1465:
1461:
1460:
1456:
1449:
1445:
1438:
1434:
1429:R-value Testing
1423:
1419:
1405:
1395:
1389:
1387:
1383:
1382:
1378:
1369:
1367:
1359:
1358:
1354:
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1335:
1334:
1330:
1321:
1319:
1311:
1310:
1306:
1299:
1272:
1271:
1267:
1260:
1241:
1240:
1236:
1229:
1202:
1201:
1197:
1190:
1182:. p. 508.
1171:
1170:
1163:
1156:
1129:
1128:
1121:
1114:
1095:
1094:
1087:
1080:
1053:
1052:
1045:
1038:
1019:
1018:
1007:
1000:
981:
980:
973:
966:
951:ASHRAE Handbook
946:
945:
941:
923:
922:
913:
906:
898:. p. 276.
887:
886:
882:
875:
856:
855:
851:
844:
825:
824:
813:
806:
787:
786:
782:
775:
756:
755:
746:
737:
735:
727:
726:
722:
715:
707:. p. 676.
696:
695:
691:
682:
680:
672:
671:
667:
662:
656:
556:
502:
501:
467:
462:
461:
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403:
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329:
323:
299:fiberglass batt
249:
248:
225:
179:
167:
126:
113:
108:
107:
86:
73:
68:
67:
43:fiberglass batt
22:
21:
20:
12:
11:
5:
1678:
1676:
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1539:
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1482:
1454:
1443:
1432:
1417:
1408:|offline=
1376:
1352:
1328:
1304:
1297:
1291:. p. 51.
1279:. London, UK:
1265:
1259:978-1609830014
1258:
1234:
1227:
1221:. p. 40.
1209:. London, UK:
1195:
1188:
1161:
1154:
1148:. p. 40.
1136:. London, UK:
1119:
1112:
1085:
1078:
1072:. p. 39.
1060:. London, UK:
1043:
1036:
1026:. Oxford, UK:
1005:
998:
992:. p. 22.
971:
964:
939:
911:
904:
880:
873:
867:. p. 28.
849:
843:978-1498715270
842:
811:
804:
780:
773:
767:. p. 97.
744:
720:
713:
689:
664:
663:
661:
658:
654:
653:
643:
609:imperial units
597:
596:
595:(ft·°F·h/BTU).
574:
573:
555:
552:
512:
509:
483:
476:
473:
458:
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322:
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259:
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222:imperial units
133:
129:
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116:
93:
89:
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76:
23:
15:
14:
13:
10:
9:
6:
4:
3:
2:
1677:
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1659:
1651:
1645:
1642:tag (see the
1637:
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1471:
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1455:
1452:
1447:
1444:
1441:
1436:
1433:
1430:
1426:
1421:
1418:
1413:
1400:
1386:
1380:
1377:
1365:
1364:
1356:
1353:
1341:
1340:
1332:
1329:
1317:
1316:
1308:
1305:
1300:
1294:
1290:
1286:
1282:
1278:
1277:
1269:
1266:
1261:
1255:
1251:
1247:
1246:
1238:
1235:
1230:
1224:
1220:
1216:
1212:
1208:
1207:
1199:
1196:
1191:
1185:
1181:
1177:
1176:
1168:
1166:
1162:
1157:
1151:
1147:
1143:
1139:
1135:
1134:
1126:
1124:
1120:
1115:
1109:
1105:
1101:
1100:
1092:
1090:
1086:
1081:
1075:
1071:
1067:
1063:
1059:
1058:
1050:
1048:
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1039:
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1029:
1025:
1024:
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1014:
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991:
987:
986:
978:
976:
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967:
961:
957:
953:
952:
943:
940:
935:
931:
927:
920:
918:
916:
912:
907:
901:
897:
893:
892:
884:
881:
876:
870:
866:
862:
861:
853:
850:
845:
839:
835:
831:
830:
822:
820:
818:
816:
812:
807:
805:0-8493-0866-6
801:
797:
793:
792:
784:
781:
776:
774:0-8031-1183-5
770:
766:
762:
761:
753:
751:
749:
745:
733:
732:
724:
721:
716:
710:
706:
702:
701:
693:
690:
678:
677:
669:
666:
659:
657:
651:
647:
644:
641:
637:
634:
633:
632:
629:
625:
622:
619:
615:
612:
610:
606:
602:
601:no difference
594:
590:
586:
582:
579:
578:
577:
571:
567:
564:
561:
560:
559:
553:
551:
547:
545:
541:
536:
534:
530:
526:
510:
499:
481:
474:
471:
440:
437:
432:
426:
417:
410:
407:
398:
393:
390:
385:
382:
375:
374:
373:
372:
371:
369:
365:
361:
359:
354:
351:
347:
342:
338:
334:
328:
320:
318:
316:
312:
307:
305:
300:
295:
291:
257:
254:
246:
242:
238:
234:
229:
223:
219:
215:
214:no difference
211:
207:
202:
200:
196:
191:
189:
185:
177:
173:
164:
160:
156:
152:
148:
131:
127:
123:
118:
114:
91:
87:
83:
78:
74:
64:
60:
56:
52:
44:
39:
32:
28:
19:
1654:Cite error:
1632:Cite error:
1629:
1605:
1598:
1572:
1566:
1555:, retrieved
1549:
1542:
1528:
1514:
1491:
1485:
1474:. Retrieved
1469:
1457:
1446:
1435:
1420:
1388:. Retrieved
1379:
1368:, retrieved
1362:
1355:
1344:, retrieved
1338:
1331:
1320:, retrieved
1314:
1307:
1275:
1268:
1244:
1237:
1205:
1198:
1174:
1132:
1098:
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1037:019-860522-6
1022:
984:
948:
942:
933:
929:
890:
883:
859:
852:
828:
790:
783:
759:
736:, retrieved
730:
723:
699:
692:
681:, retrieved
675:
668:
655:
649:
645:
639:
635:
630:
626:
623:
620:
616:
613:
598:
575:
563:square-metre
557:
548:
537:
532:
528:
524:
459:
367:
363:
362:
355:
349:
336:
332:
330:
308:
303:
293:
236:
230:
203:
195:polyethylene
192:
183:
154:
150:
146:
54:
48:
581:square-foot
1557:5 February
1476:2016-03-17
1390:2014-10-29
1370:5 February
1346:5 February
1322:5 February
738:5 February
683:5 February
660:References
540:tog (unit)
538:See also:
325:See also:
241:convection
199:misleading
151:multiplied
59:conductive
18:User:Reuqr
1662:help page
1644:help page
1285:Routledge
1281:Earthscan
1215:Routledge
1211:Earthscan
1142:Routledge
1138:Earthscan
1066:Routledge
1062:Earthscan
865:CRC Press
834:CRC Press
796:CRC Press
508:Δ
498:heat flux
475:˙
424:Δ
411:˙
294:increases
245:radiation
184:RSI-value
178:per unit
124:−
84:−
1399:cite web
603:between
546:rating.
350:U-factor
346:humidity
333:U-factor
315:U-factor
226:window″;
216:between
936:(3): 6.
496:is the
339:is the
337:U-value
304:surface
186:if the
168:layers.
147:divided
55:R-value
31:Aerogel
1617:
1586:
1580:ASHRAE
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1295:
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840:
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771:
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566:kelvin
460:where
180:area.″
161:or in
53:, the
1573:2013
1496:Wiley
1466:(PDF)
1180:Wiley
1104:Wiley
949:2013
896:Wiley
705:Wiley
544:duvet
237:other
206:below
159:Watts
16:<
1615:ISBN
1584:ISBN
1559:2018
1500:ISBN
1412:help
1372:2018
1348:2018
1324:2018
1293:ISBN
1254:ISBN
1223:ISBN
1184:ISBN
1150:ISBN
1108:ISBN
1074:ISBN
1032:ISBN
994:ISBN
960:ISBN
900:ISBN
869:ISBN
838:ISBN
800:ISBN
769:ISBN
765:ASTM
740:2018
709:ISBN
685:2018
607:and
589:hour
570:watt
568:per
331:The
243:and
220:and
163:BTUs
335:or
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132:1
128:T
119:2
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