常用(yong)(yong)的(de)中(zhong)(zhong)空(kong)玻(bo)璃間(jian)隔(ge)層(ceng)(ceng)厚(hou)(hou)(hou)度(du)為6mm，9mm, 12mm等(deng)，氣(qi)體間(jian)隔(ge)層(ceng)(ceng)的(de)厚(hou)(hou)(hou)薄與(yu)傳熱(re)阻(zu)的(de)大(da)小有著直(zhi)接的(de)聯系。在(zai)玻(bo)璃材質、密封構造相同的(de)情況下(xia)(xia)，氣(qi)體間(jian)隔(ge)層(ceng)(ceng)越(yue)大(da)，傳熱(re)阻(zu)越(yue)大(da)。但氣(qi)體層(ceng)(ceng)的(de)厚(hou)(hou)(hou)度(du)達到(dao)(dao)一定程(cheng)度(du)后(hou)，傳熱(re)阻(zu)的(de)增長率就很小了(le)。因為當(dang)氣(qi)體層(ceng)(ceng)厚(hou)(hou)(hou)度(du)增大(da)到(dao)(dao)一定程(cheng)度(du)后(hou)，氣(qi)體在(zai)玻(bo)璃之間(jian)溫差的(de)作用(yong)(yong)下(xia)(xia)就會產(chan)生(sheng)(sheng)-定的(de)對(dui)流(liu)過(guo)程(cheng)，從(cong)而減低了(le)氣(qi)體層(ceng)(ceng)增厚(hou)(hou)(hou)的(de)作用(yong)(yong)。如圖6-18所示，氣(qi)體層(ceng)(ceng)從(cong)1mm增加到(dao)(dao)9mm時(shi)(shi)(shi)，白玻(bo)中(zhong)(zhong)空(kong)充(chong)(chong)填(tian)空(kong)氣(qi)時(shi)(shi)(shi)K值下(xia)(xia)降(jiang)37%，Low-E中(zhong)(zhong)空(kong)玻(bo)璃充(chong)(chong)填(tian)空(kong)氣(qi)時(shi)(shi)(shi)K值下(xia)(xia)降(jiang)53%，充(chong)(chong)填(tian)氬氣(qi)時(shi)(shi)(shi)下(xia)(xia)降(jiang)59%。從(cong)9mm增加到(dao)(dao)13mm時(shi)(shi)(shi)，下(xia)(xia)降(jiang)速率都開始變緩，13mm以后(hou)，K值反而有輕微的(de)回升。所以，對(dui)于6mm厚(hou)(hou)(hou)度(du)玻(bo)璃中(zhong)(zhong)空(kong)組合，超過(guo)13mm的(de)氣(qi)體間(jian)隔(ge)層(ceng)(ceng)厚(hou)(hou)(hou)度(du)再增大(da)不會產(chan)生(sheng)(sheng)明顯的(de)節能效果。