Stage 6 – Filling the 4-inch PVC pipes (columns) and the 2-inch PVC arches
Stage 6 includes filling in the 4-inch and the 2-inch PVC pipes with mortar, which in the case of the 2-inch pipes (arches) is made of sand, gravel, and cement (Photo 70), as suggested: six 18-liter cans, plus six 18-liter cans of gravel or gravel powder, plus 50 kilos of cement. The mortar should not be too thick to facilitate its pouring into the pipes (Photos 71 and 72). The 2-inch PVC pipes should be filled from both sides so that the mortar fills in the entire inner space to make the pipe more resilient and durable (Photo 73).
The same procedure should be used in filling in the 4-inch PVC pipes, with the mortar being poured from the top of the column and occupying the inside space that previously received the iron bar/trellis (Photos 74, 75 and 76). Next, it is necessary to use a coupler to reduce 4 inches to 2 inches (Photo 77). The coupler is to be placed at the top of the columns (Photos 78, 79 and 80). These couplers should also be filled in with mortar (Photos 81 and 82). This process requires, firstly, correct positioning of the 4 to 2-inch pipe reducing coupler (Photo 83) on both sides of the greenhouse to ensure the arches will connect properly; and secondly, that the reduction coupler be filled in with mortar only up to the point where it goes from 4 to 2 inches (Photos 83, 84, and 85). It is advisable to allow three or four days for the mortar to dry up before proceeding with the construction of the agricultural greenhouse with alternative materials.