Siman 359
Presented here for study, not as a practical ruling. The Shulchan Aruch rules by Sephardi custom, the Rema's glosses by Ashkenazi custom, and the Kitzur follows Ashkenazi custom. For a practical question, ask your rabbi.
א רְחָבָה שֶׁאֲחוֹרֵי הַבָּתִּים יְתֵרָה עַל בֵּית סְאָתַיִם וְלֹא הֻקְּפָה לַדִּירָה, אֵין מְטַלְטְלִין בָּהּ אֶלָּא בְּד' אַמּוֹת. וְאִם פֶּתַח לָהּ פֶּתַח מִבֵּיתוֹ וְאַחַר כָּךְ הִקִּיפָהּ, אֲפִלּוּ אִם יֵשׁ גֹּרֶן בֵּינָהּ לַבַּיִת, הָוֵי הֶקֵּף לַדִּירָה. הַגָּה: וּמַה שֶׁאֵין אָנוּ נִזְהָרִין לְטַלְטֵל בַּחֲצֵרוֹת שֶׁאֲחוֹרֵי הַבָּתִּים, מִשּׁוּם דְּבַזְּמַן הַזֶּה סְתָמָן מֻקָּפִין לַדִּירָה כְּמוֹ שֶׁנִּתְבָּאֵר לְעֵיל גַּבֵּי קַרְפָּף (דִּבְרֵי עַצְמוֹ).
1 The Law of an Open Area Behind the House: If an open area behind the house is bigger than two seahs and is not enclosed for dwelling, we only carry in it within four amot. If he made an opening from his house and afterwards surrounded the area [with walls], even if there is a threshingfloor between the area and the house it is considered enclosed for dwelling. Rema: We are not careful regarding carrying in the yards behind houses because in this time, generic areas are enclosed for dwelling, as was explained above regarding enclosed spaces (his opinion).