Gut Moed R' Wasserman, Is it possible to say that Rav Shlomo Zalman's psak is for eretz yisroel? In America, each floor of a residential home and the top floor, as well as right under the roof is made out of wooden joists. While they sit vertically, perhaps the psak of the Shulchan Aruch remains for those residing in the US. From my limited time in E"Y, it seems that wood is rarely used for construction there.

Gut Moed R' Wasserman, Is it possible to say that Rav Shlomo Zalman's psak is for eretz yisroel? In America, each floor of a residential home and the top floor, as well as right under the roof is made out of wooden joists. While they sit vertically, perhaps the psak of the Shulchan Aruch remains for those residing in the US. From my limited time in E"Y, it seems that wood is rarely used for construction there.