Mobile homes are lighter than site-built houses. Thus, according to studies that have assessed housing damage during hurricanes, mobile or manufactured homes are highly vulnerable to flipping over and blowing away in high winds unless they’re anchored to the ground.
The US Department of Housing and Urban Development (HUD) requires manufactured homes to be secured with hurricane tie-downs. Protecting your house from high winds is essential, especially if you live in a hurricane zone. Tie-downs give you that extra protection and peace of mind.
Many do-it-yourself enthusiasts want to construct their mobile homes. While installing hurricane tie-downs isn’t particularly challenging, it’s crucial to use the appropriate tie-down components and adhere to the installation guidelines specified by the HUD.
This article will explain what mobile home hurricane tie-downs are and the various types, how to install them, and how to make them more effective.
What Are Mobile Home Tie-Downs?
Mobile home hurricane tie-downs secure a home to the ground. They are made up of straps and anchors designed to stabilize a home and prevent it from overturning and blowing away in high winds. Besides securing the floor frame to the ground, some tie-downs offer protection for the roof of older and lightweight homes.
There are two types of tie-downs: over-the-top tie-downs and frame anchors.
Over-the-top tie-down straps are positioned over the siding and roof and connect to anchors on either side of the house. They may be exposed or concealed. These tie-downs are usually installed in older mobile homes.
In the case of frame anchors, the anchoring straps set into the ground are attached to the building’s floor frame or steel rails. Frame anchors are installed in newer mobile homes that are structurally superior to older models.
Do Mobile Home Hurricane Tie-Downs Work?
Mobile home hurricane tie-downs work only if installed appropriately and adhere to the latest building code requirements. Over-the-top tie-downs work best for lightweight, single-wide homes, while frame anchors are adequate for newer and heavier double-wide homes.
Below are some tips on how to make mobile home tie-downs work most effectively:
Adhere to the Manufacturer’s Installation Specifications
All mobile homes must be anchored according to the installation guidelines prescribed by the manufacturer.
If the manufacturer’s guidelines aren’t available, the building must be anchored following the guidelines specified by the authority responsible for issuing permits and carrying out on-site inspections.
In many areas, the authority having jurisdiction is the city or county building department.
Install the Appropriate Type of Tie-Down
Single-wide homes require diagonal and vertical tie-downs. Double-wide homes typically require diagonal tie-downs. Older manufactured homes require over-the-top tie-downs, while frame anchors suffice for newer homes.
However, the type of tie-downs required also depends on several other factors, including:
The Wind Zone the Home Is Designed For
Your mobile home is designed to be located in a specific wind zone. The home’s data plate contains this information. The specifications include:
- Mobile homes designed for wind zone 1 usually require diagonal tie-downs.
- Homes intended for wind zones 2 and 3 require diagonal and vertical tie-downs.
- Homes with a ‘D-sticker’ designed to be located within 1,500 feet (457.2 m) of a coastline in wind zone 3 must comply with additional tie-down installation requirements.
The Year the Home Was Constructed In
HUD has guidelines for spacing tie-downs. These guidelines are updated regularly to ensure mobile homes are wind-resistant.
You’ll need to know when your house was constructed to ensure it adheres to the current guidelines. To find out when your home was constructed, consult the deed or your local housing authority.
Schedule Regular Inspections
The Federal Emergency Management Agency (FEMA) recommends that you check your home’s tie-downs every two years if you live in a coastal region and every five years if your home is located inland. An inland region is more than 3,000 feet (914.4 m) from the coast.
How To Anchor a Mobile Home With Tie-Downs
While anchoring a mobile home with tie-downs isn’t highly complicated for experienced do-it-yourselfers, it’s always best to seek professional advice and help if you’re a newbie.
Some challenging aspects of the installation process are choosing the appropriate type of tie-down for your home and ensuring it has the correct dimensions, selecting an anchor based on the type of soil your house will be located on, fixing the tie-downs to the anchor, and securing the anchor.
The following are the steps for anchoring mobile homes with hurricane tie-downs.
1.) Ensure the House Is Level
Ensure your home is standing on level ground before installing the tie-downs. Here’s how to check the level:
- First, position a level in the center of the beam.
- Check the bubble.
- Move the level to the next support beam and check the bubble.
- Continue moving the level and checking the bubble till you reach the end of the main support pier.
- Go to the other side of the home.
- Position the level in the center of the beam and check the bubble.
- Repeat till you reach the end of the support beam.
2.) Check the Installation Guidelines
Check the mobile home installation guidelines specified by the manufacturer. Additionally, you’ll need to find out the wind zone the manufacturer designed your home for.
The number of anchors you have to install depends on the wind zone designation of your home. If your home wasn’t designed for high winds, you’d need to take extra steps to protect it.
3.) Determine the Type of Soil
Depending on the type of soil the home sits on, you may have to install anchors five feet deep.
A building inspector can help you determine the soil type and advise how deep to install the anchors. If you already know the depth, you can install them yourself, ensuring they are deep enough to make an impact should a storm hit.
4.) Select the Appropriate Anchor
The type of soil your house sits on, and the location of the groundwater table on the site determine the kind of anchors you have to install.
For instance, auger or screw-in anchors should be used for hard or soft soil. Rock or drive anchors can be attached to a coral or rock base.
5.) Choose the Appropriate Hook-Up System
A mobile home tie-down is connected to the anchor via a hook-up system that lets you adjust the tension. The hook-up system should be weather- and corrosion-resistant and support at least 4,725 lbs (2,143.22 kilograms).
The choice of a hook-up and tension system depends on the type of tie-down you want to install.
6.) Mark the Spots Where Wires and Cables Are Installed
Before digging the ground and installing the anchor and the tie-downs, mark where electricity, gas, water, sewer, and phone cables are located.
You can do this using wooden pins in the ground. This process is essential to secure the integrity of these points since they will need adequate space.
7.) Position the Tie-Downs
Some guidelines to follow while installing over-the-top tie-downs, include:
- Position the strap or cable over a roof rafter and away from doors and windows.
- Protect the roof’s edges with a protector placed under the strap at the roof’s edge.
- Choose high-quality commercial protectors to distribute the pressure of the strap.
8.) Install the Anchor
Follow the installation instructions for specific types of anchors. Keep the following in mind when installing anchors:
- Install the anchor vertically for vertical tie-downs.
- Install the anchor at an angle of at least 40 degrees for frame or diagonal tie-downs.
- However, you can install the anchor vertically for frame tie-downs if you use a stabilization device to prevent the anchor from getting displaced sideways.
- You can stabilize an anchor by pouring a concrete collar that should be at least 18 inches (45.72 cm) deep and 10 inches (25.4 cm) in diameter.
Here’s a YouTube video by MHIposts that demonstrates how to install an anchor:
9.) Adjust the Tension
The straps shouldn’t be loose. Instead, they should have some tension to prevent the home from swaying in high winds and becoming loose.
Move alternately between the two sides of the house while checking and adjusting the tension in the straps.
Here’s a YouTube video posted by Country Roots Farm on how to install mobile home tie-downs:
If you intend to install the tie-downs yourself, have a building inspector or a trained and licensed installer check the work after you’ve completed it.
Can Hurricane Tie-Downs Secure a Mobile Home Roof?
It isn’t uncommon for mobile home owners to wonder if hurricane tie-downs can also protect the roof of their homes. Frame anchors secure the house’s frame, but are they enough to prevent the walls and the roof of the building from tearing off during a hurricane?
Hurricane tie-downs can secure a mobile home roof. Over-the-top hurricane tie-downs should be installed in single-wide mobile homes along with frame anchors. Double-wide mobile homes are more stable, so they typically don’t require over-the-top hurricane tie-downs.
A single-wide home doesn’t have the internal strength to transmit hurricane loads to its supporting steel frame. So, the walls and the roof of the structure have to bear the wind forces.
According to the National Research Council Canada, the roof of a single-wide mobile home needs the additional protection offered by over-the-top hurricane tie-downs.
Conclusion
Climate change is intensifying tropical storm wind speeds and making hurricanes stronger. More and more inland areas are being affected by hurricanes as climate change shifts these weather systems toward the poles.
In such a scenario, mobile home owners should install hurricane tie-downs not only in coastal regions and the tornado-prone Midwest but also in areas where gusty winds are expected. They must ensure that they adhere to the HUD guidelines while installing these.
It’s best to have a professional installer do the work and have a building inspector check the installation afterward.
Sources
- SIP (Super Inspection Pros): Manufactured Home Tie-Down Inspections: Why They Matter
- InterNACHI: Tie-Downs for Manufactured Homes
- How to Look At a House: How often should mobile/manufactured home foundation tie-downs be checked?
- How to Look At a House: What are the tie-down requirements for a mobile home?
- MH Villager: Mobile Home Leveling FAQs: What Homeowners Need to Know
- InspectAPedia: Manufactured Home & Mobile Home Tie-Downs & Stabilizing Systems
- NRC Publications Archive: Wind Forces on Mobile Homes
