כה אמר ה' השמים כסאי והארץ הדם רגלי ... (ישעי' סו-א)
The Haftorah of Shabbos Rosh Chodesh discusses the grandeur of Hashem, and while we may read this Haftorah on any other Shabbos of the year, being that it now falls out on Parshas Noacha connection must be there.
Yeshaya HaNavi’s opening words describe how Hashem declares heaven His throne and earth a “footstool” wondering where a house could be built for Him on earth that could withstand the awe-inspiring power and holiness of the shechina. The question begs to be asked; if Hashem does not believe that the world could withstand his holiness, then why have Klal Yisroel attempt to build a house for Him altogether?
Chazal note that it took well over 400 years from the time Klal Yisroel came into Eretz Yisroel until Shlomo HaMelech actually completed the construction of the Bais HaMikdash, partly because the world was meant to observe and see Klal Yisroel busying themselves with its construction in the hopes that they will recognize the true mastery of Hashem.
Furthermore, Rashi tells us that even though Hashem could have saved Noach in many other ways, Hashem burdened him with constructing the Ark for 120 years so that he could help the people around him repent and avoid the flood.
Perhaps, the two are linked. Klal Yisroel is meant to be a light unto the nations and a shining example of what a human being is meant to be. We are supposed to put our heads down and do the work Hashem wishes from us, and through our seemingly mundane actions, the world will become a better place.