Abstract: In preparation of a building to have its roof structure secured to its vertical wall structure by tie-down straps, a plurality of anchors are secured to the foundation in pairs, on opposite sides of the building, and a tie-down strap guide is secured over the ridge of the building between the related anchors. The tie-down straps are connected to anchors by tensioning devices which include a ratchet and may include a connector to permit the ratchet to be disposed at a distance from the anchor. Ridge guides retain the straps above the rafters and/or gable ends. The anchors comprise eye bolts with reinforcing webs thereon. Blocks located at the eaves prevent the tie-downs from crushing the drip edge of the roof; pass-through holes in gutters permit the tie-down straps to pass through the gutters without crushing them; the pass-through holes in the gutters may have vertically extending wells associated therewith to prevent rainwater from flowing through the pass-through holes.