the roof of my home

I was looking at the internal structure of a roof, at the metal beams that held it in place. Although I was not familiar with the house underneath, I knew it to be my home. The metal beams formed a pyramid shape: a square around the bottom with four beams reaching up and in from each of the corners, meeting in the middle point at the top. Each length of beam was actually made up of smaller beam sections, interlocking, so that the structure was, theoretically, quite sturdy. I was up inside the structure, looking around, and, from this vantage, I could see that there were three pieces of the beams missing, all from different parts of the structure and each a different length. I knew that without these three pieces, the roof was both incomplete and unstable. I climbed down and searched the house for the missing pieces. I found all three in different rooms of the house. The longest piece I found last, tucked away behind the door of the bedroom cupboard. I then set about putting each beam piece in place, the two shorter pieces first and then, most challengingly, the longest beam.