All of our Storm Shelters and Safe Rooms are installed by anchoring the base structure to an existing concrete slab/floor. If you do not have an existing concrete slab/floor, we have a Licensed Professional Engineers concrete specifications recommended for each one of our Storm Shelter and Safe Room models. We recommend Hilti Anchor System with HIT-HY 200-R Injectable Mortar with HIT-Z rod 1/2″ anchor bolts with over 5,000 lbs. pull out strength per anchor. The HILTI HIT-HY 200-R Adhesive Anchors SafeSet System is the only anchor system we recommend. Your Storm Shelter/Safe Room is complete with its own HILTI Install Kit.