Use an old door frame, an metal dining table base from the 70's and some re-claimed wood for the seating...very possible! Some shop time and a bit of dowel creativity, and bingo...a contemporary yard bench.:
product designer Kana Nakanishi‘s wonderful W1200xD380xH480 Finnish birch wood bench. Named simply after its dimensions, the seat’s U-shaped back rest doubles as its legs, sitting diagonally through the base.