Inspect the area where you will tie down the travel trailer. The anchor systems will be different for paved or unpaved areas. If you plan to install a new concrete base under your trailer, install new concrete anchors at the same time. Use screw anchors for loose or dense soil, concrete block dead-man anchors for loose soil, drive anchors for rocky or coral soils and hard rock anchors for attachment to rock.
Install two or three vertical anchors per side and four to six diagonal anchors per side for most trailers 50 feet or less in length. Manufactured home design must follow the Manufactured Home Construction and Safety Standards at 24 CFR 3280, part of the HUD Code. Included in the HUD Code are wind zone designations for areas with higher potential wind speeds. Zone I covers non-coastal areas of the continental United States, zones II and III cover the coastal areas of the eastern and southern United States and Alaska. Travel trailers not being used as permanent living spaces may not have mandated tie-down regulations. Check with your local building inspectors for requirements where you live.
Install wood or concrete piers to raise the trailer above the ground. The trailer should be level and the tires should be at least 2 inches above the ground. Use wider foundation blocks on loose soil to prevent settling.
Install vertical anchors directly under the trailer frame if you are connecting the tie-downs to the bottom of the trailer. Place diagonal anchors at a 40 to 50 degree angle out from the trailer frame. Use diagonal anchors in addition to vertical anchors to prevent the trailer from being moved sideways in high winds. A combination of vertical and diagonal tie-downs will provide adequate protection from all but the greatest storm winds.
Determine the type of tie-down you will be using. Purchase tie-downs with a minimum breaking strength of 3,150 pounds and at least 50 percent overload or 4,725 pounds. Fiber straps must be part of outdoor use. Cables or steel straps should be galvanized or stainless steel. Check with your local building inspectors for strap recommendations or restrictions.
Install the tie-down straps or cables per manufacturer's instructions. Tie-downs can run from the trailer frame directly to the ground, or you can install tie-down straps over the top of the trailer, connecting to the anchor point on the opposite side of the trailer. Align the straps with roof trusses or other strong points on the trailer roof to avoid crushing the trailer. Use corner and roof protectors for overhead straps. Use adjustable tension devices on all straps or cables to allow for adjustment of the tie-downs.
Turn the tie-down adjustments slowly on each side, using tools specified by the tie-down manufacturer to balance the tension on all tie-down points. Look for loose anchors and re-position them if they do not hold in the ground. Proper tension will secure the trailer without causing any structural strain or deforming the frame or roof.
