When strong winds blow, manufactured homes need special protection. No matter where you live, you need tie-downs and anchors to keep your manufactured home stable and secure. Before you start the job, you should understand why this wind protection system is necessary, and know the basic requirements for tie-downs and anchors. You also need to become familiar with all the components that make up your anchoring system. It’s a good idea to consult with an experienced professional installer or building inspector if you have any questions or doubts about the installation.
Manufactured homes must have anchors and tie-downs to keep them in place during high winds. Compared to site-built homes, manufactured homes are relatively lightweight. They have flat sides and ends, and they are built on frames rather than foundations. Almost all manufactured homes are elevated, situated on top of some sort of pier or foundation system. Wind can get under the homes and lift them up. In addition, the wind passing over the top of your manufactured home can create an uplift force.
To resist wind forces, you need two different types of tie-downs. In older homes, a vertical or over-the-top tie-down is needed to compensate for the uplift force. A diagonal or frame tie-down is needed to compensate for both lateral and uplift forces. Singlewide manufactured homes need both types of tie-downs. Doublewide homes only need the diagonal ties.
Anchoring system components
Types of tie-downs. The type of tie-down you select usually depends on when your manufactured home was built. Older homes often have exposed over-the-top tie-downs. This is an effective system, but it does detract from the appearance of your house. The straps are placed over the siding and roof. Until recent years, most manufactured homes came equipped with concealed over-the-top tie-downs. These straps are located just under the exterior siding and metal roof. The end of the strap hangs out under the manufactured home. Newer model homes might not have any type of over-the-top tie-down. Because of increased structural strength of manufactured homes, these models are secured with anchoring straps attached to the home’s steel frame rails, called frame anchors. Doublewides are also secured with frame anchors.
Types of anchors.You’ll find anchors available for different types of soil conditions, including concrete slab. Auger anchors have been designed for both hard soil and soft soil. Rock anchors or drive anchors allow attachment to a rock or coral base. This type of anchor is also pinned to the ground with crossing steel stakes. If you will be pouring a concrete base, you can install a concrete anchor first.
You need to know your soil type to select the right anchor. Soil classifications usually include: rock/hard pan, heavy, sandy gravel, heavy sand, silty gravel, clayey gravel, clay, silty clay, clayey silt, uncommitted fill or peat/organic clay.
Whatever type of anchors you select, carefully follow the installation instructions. Auger anchors (screw-in anchors) can be installed manually by inserting a metal bar through the top of the anchor for added leverage or with a machine designed for this purpose. It’s important to screw this type of anchor in. Do not dig a hole to install.
Hook-up and tension device: The tie-down must be connected to the anchor with a system that allows for adjusting the tension. It must also be weather resistant and strong enough to support as much weight as the anchor and tie-down. If the tie-down is fastened to a ground anchor with a drop-forged turnbuckle, the turnbuckle should be ½ inch or larger galvanized steel. The turnbuckle should have forged or welded eyes, not hook ends.
The roof protector. If you have exposed over-the-top tie-downs, you must have some so