Q. Kvod Harav. Thank you so much for all your divrai torah and yard hospitality. It is so good to be able to be back davening betzibur.
I was listening to a shiur today by Rav Shachter shlita and he called into question a practice that is done in backyard minyanim.
According to what he said all ten of a minyan should be in the same room in order for kaddish, kedusha, and kriyas hatorah.
He said that even a mechitza of ten tefachim ( which does exist between two backyards or from a deck to the yard below )is enough to consider it a separate room and create problems. He said if ten are gathered in one space those on the outside can answer amen but ten need to be together. 
 I am recent to backyard minyanim and maybe this has already been discussed but I was wondering if yourself or if R. Shlomo Miller shlita discussed the matter and if there is sufficient reason to be makpid on this matter?
A. On question 2610 the first of several regarding backyard minyonim, although there are fences between the properties, we wrote “Horav Shlomo Miller’s Shlit’a opinion is that although there are dissenting opinions, in times of need even if the fence is tall and one can only see the other participants when standing on his porch, and watching over a wooden fence, he can still be part of the minyan.
A person in quarantine can also join by watching from his property, as Horav Pam Shlit’a commented, “he is not in nidui (excommunicated).”
However, they may accept or even offer to recite kaddish for those unable to come to a minyan.
(See also questions 2629, 2630. 2638, and others)
Rabbi A. Bartfeld as advised by Horav Shlomo Miller Shlit’a