Usually, closed topics are only found in 3 (first two and the last) forums. And usually, all opened and new topics remain on top and on the first page. And also they do not significantly count towards page loading.

And again, all topics should be in their correct place and not be mixed up in a forum for easy finding.

So it does not seems necessary to get an extra headache for moving the closed topic to a sorage forum (my opinion only).

her closed topic ka storage oos ka apna thread hai
koi bhi kisi bhi closed topic ko waha search ker sakta hai.i think yeh ziada asan hai.
baqi aap ka idea Admin tak pohanch gaya.thanx for this