How to Properly Anchor a Shed: The Only Guide You Need

Batten down the hatches, it’s going to blow! We’ve all seen pictures of sheds tumbling in the wind or floating down the street. If you’re lucky, it’s not yours. How do you protect your belongings and keep your shed where you put it? How do you properly anchor your shed?

That snow blower or 4-wheeler should be heavy enough to keep it there or maybe some bricks? Nope, won’t work. If the wind can roll a double wide trailer and water float a house, then we need a better solution. After the last major wind blew a garden shed across the road ahead of me, I started looking.

The best way to anchor a shed, in my opinion, is with concrete piers. They’re inexpensive and not too difficult to put in:

• Drill or dig the holes, tamp some gravel into the bottom
• Slide a sonotube in to form it up
• Level it to the needed height, and fill it with concrete
• Set a galvanized anchor bracket in before the concrete sets
• Align and level the brackets and you’re all set to secure your shed

There are other methods you can use too. In this article, I’ll show you other ways to tie down your storage shed and also discuss some of the reasons your outbuilding should be anchored. Hopefully this article catches you before the wind catches your shed.

What are Shed Tie Downs and Why Do You Need Them?

Shed tie downs are a way to secure a shed to the ground to prevent it from being moved or lifted by wind or water.

There are cables, metal straps, galvanized connectors, twist in anchors and concrete tie down options. The size and material of the shed determine the minimum type or size of tie down needed.

There has been an increase in windstorms and flooding rains across North America in recent years. It has brought damage to many areas that haven’t experienced it in many years.

National Building Codes and local ordinances are modified to reflect the change and should be reviewed. Better safe than sorry.

Meet Local Regulations

With each new disaster come recommendations to help reduce the potential for future damage. To encourage compliance, local codes are amended to reflect the trend and needs.

Some local ordinances are very helpful and logical. They identify what the minimum requirement is for different shed sizes and materials.

Some areas have seen it as a cash grab and added new zoning permits for sheds under specific square footage. Fines tend to be larger than the cost of the permit, so better to comply and tie down rather than tear down.

Here’are some examples:

Add Strength and Stability

Securing your storage shed to the ground adds strength to the structure and stability. Smaller sheds are lighter, especially if made of plastic or light steel.

They rattle and vibrate when you open the door, when you cough, or with each passing breeze. Running a cable from one side to the other at both ends and secured to the ground adds strength and stability to the structure. It ensures your shed should be where you put it when the next big wind blows.

Safety

Thunderstorms can have gusts strong enough to snap trees or tumble trailers, hurricane tie downs are to protect your property and others too. If you have electrical power to your shed and the wind carries it away, you have an added danger.

Anything that prevents a shed from cartwheeling across the neighborhood keeps others safe. Like the belt holding your pants where they belong, the tie down keeps your shed where it belongs.

Protect Against Wind Damage

Did you know there are wind maps which show wind ratings for every part of the continent? Your local government often uses the wind maps to determine requirements to secure sheds and other buildings.

You want to protect your shed contents, so protecting your shed from wind damage is important. By securing your shed you’re also protecting others too.

Before buying or building a shed, determine how to secure it from the wind.

Insurance Reasons

With rising property damage costs due to the wind, comes a rise in insurance costs.

Many insurance companies have a rider that requires sheds and outbuildings to be properly secured. It covers damage to your property, and also the general public. If tied down properly, you save on your insurance.

Types of Shed Anchoring Systems

There are many types and styles of shed anchors. Your local government may have set minimum requirements so it’s a good idea to check their documentation.

Concrete Expansion Anchors Concrete expansion anchors are bolts to secure a structure to existing concrete. A good solution for an existing shed on a concrete pad.
Anchor Bolts Anchor bolts are usually for new construction and are inserted into concrete before it fully cures. After putting them into the concrete, jig it up and down to reset the concrete around it. Make sure it is aligned and level to your shed requirements.
Foundation Anchor Plates and Straps Anchor plates and straps are used to secure a shed to a foundation. The shed may already rest on the foundation, or be a prefab being placed on a concrete or wooden foundation. They are a good way to secure a temporary or permanent shed to a foundation.
Auger Style Shed Anchors Auger style anchors are a rod with a wide helix or screw disc at the base. It is screwed into the ground; which can be difficult. A cable or strap is attached to the ring top to secure the shed. A solution for existing sheds. Another similar product has a bracket welded to the top for attaching the outbuilding foundation directly to it. It’s more practical for new construction. The advantage of both these products is they don’t disturb the ground.

By Type of Construction

New construction of a shed now includes how your shed will be secured to the ground. A concrete foundation or pilings are a permanent foundation and make it easy to secure a shed.

Foundations of slabs, deck blocks, gravel pads, plastic, grid, or wooden posts require alternate methods to secure your shed to the ground. Auger style anchors are one way.

Another is to dig or drill a hole and form up a concrete piling at each corner of your shed to secure a cable or strap to.

Retrofitting a shed depends on the type of foundation and material the shed is built with. It can be secured with auger style tie down spikes or to concrete pilings. If it sits on a concrete pad or concrete pilings, it can be secured with expansion anchors, bolts or plates and straps.

By Type of Shed

Wood Sheds are structurally heavier and often more stable. If made with joist and beam construction or joist construction they can be secured at the rim plate or beam to anchors in the ground.

The walls and roof are usually secure if properly constructed. Hurricane brackets can be added where the walls meet the roof if necessary.

Plastic sheds are often very light and need to be completely secured to the ground. Screws into plastic may hold in light gusts but aren’t reliable in heavy winds.

Cable or straps that go over the roof and secure to anchors will keep your shed and its contents more secure.

Metal Sheds are also lighter than wood construction, but sheet metal screws are more reliable into metal than plastic. The metal floor can be secured to the ground at the corners and will meet most needs.

In some windy areas, heavier anchors at the corners with straps or cables securing the walls and roof structure may be required.

Also, make sure and check out my article about how to build hurricane proof shed.

 

What is the Best Way to Anchor Your Shed to the Ground?

The best way to secure your storage shed to the ground is with concrete. Wood or metal anchors in contact with the ground will deteriorate over time.

Above ground cables, plates and bolts can be checked and replaced if they rust out. Concrete pilings sunk below the frost line are an easy and less expensive solution to a concrete slab and work as a new and retrofit solution.

Concrete lasts a long time and will help your shed last a long time too. It costs more, but what you have sitting on it is probably worth it.

 

How to Anchor a Shed to Concrete Slab

New Construction

Build Frame Directly on the Slab

When planning a new shed, a concrete slab is a great foundation and a great way to anchor your wood shed to the ground. It provides a solid floor and ground level access to your shed for heavy or wheeled equipment.

The slab is the same size as the perimeter of your outbuilding.

The perimeter of the slab is thicker (up to 8”) and acts as a footing to better support the weight of the walls and roof.

1. Install ½ x 6 galvanized anchor bolts, sometimes called J or L bolts, into the perimeter of the concrete before it cures. Make sure enough of the bolt is above the concrete to go through the plate and have room for the washer and nut. They must be 12 inches or less from the corner (you need space for double or triple studs at corner), and no more than 6 feet apart on the bottom or sill plate. Once the concrete has cured, the anchors are permanent.

2. Lay out your bottom or sill plate, marking where to drill the holes for the bolts.

3. Before securing the plate to the slab, put down sill gasket, rubber or plastic to protect the wood from direct contact with the concrete. It will minimize water damage and the chance of rot. Alternatively, you can run a bead or two of polyurethane caulking around the perimeter before securing the plate, or use pressure treated lumber. I’ve known builders to combine all three methods.

4. Place washers and nuts and tighten down the nuts with a socket wrench.

Don’t forget to install an additional anchor if you plan storing your bicycle in the shed.

Once you have the stud walls built, the sheathing should overlap the concrete by 2 inches and have 3 inches of clearance from the ground. Make sure the ground is sloped away from the foundation to prevent water damage and rot.

Advanced options

If you live in a high wind zone (Zone 1 or 2), or experience storm cells or just want added piece of mind, then you want to consider additional anchor support.

Most frame sheds are constructed with nails or screws connecting the bottom of the studs to the anchored sill or bottom plate.

The sheathing is attached and provides some lateral anchoring. Repeated buffeting by strong winds can weaken those connections.

Heavy galvanized hold down anchors are available that attach to the anchor bolts and then use heavy lag screws to attach to the stud. They hold the plate down and provide extra security against lift forces, similar to hurricane brackets on rafters or trusses.

If planning to use hold down anchors you’ll need to place your anchor bolts into the concrete to align with corner and mid-wall stud locations, and use longer anchor bolts for the added material.

Build Shed Floor Frame on Elevated Post Bases

If you’re planning to build your shed on an elevated base or foundation, it can still be well secured against wind forces. An elevated foundation can provide extra ventilation, keep wood away from ground moisture, provide access to plumbing should you convert your shed to a tiny home or office, and it may be the only way to level the ground.

Concrete pilings sunk below the frost line provide a solid foundation and a great way to anchor your shed.

1. Before the concrete sets, insert post base anchors or elevated post base anchors. Elevated post base anchors add clearance to keep wood away from standing water.

2. Align and level for beam or joist placement.

3. Once the concrete sets, you’re ready to build. Your outbuilding will be anchored to the ground and more secure from wind damage.

How to Secure Shed to an Existing Concrete Slab

If you’re building a new shed on an existing slab that has no anchors, it is fairly easy to install concrete expansion anchors to secure your shed to the pad. The anchors should be placed within 12 inches of the corners and no more than 6 feet apart on the wall plate.

The placement of holes at the corners is determined by the type of anchor you’re using. If it is only a concrete expansion anchor you need to leave space for a double or triple stud corner, but be no more than 12 inches from the outside corner.

If you plan to use hold downs with the anchors, then you need the holes to be closer to the corner studs. Also, adjust the depth of the hole to have enough bolt above the bottom plate to go through the hold down and for the washer and nut.

1. Mark on the concrete where the ½” X 7” concrete expansion anchors will go.

2. Use a hammer drill with a ½” concrete bit to make a hole the same size as the anchor bolt diameter. Set the drill guide for the hole depth or put tape on the bit as a depth guide – about 4 ½” to 5” deep if not using a holdown.

Keep your drill perpendicular to the concrete, you don’t want the anchor on an angle.The hole should be the depth of the anchor shaft less the thickness of the material being anchored, plus the nut and washer (and hold down if applicable).

3. Once the holes are drilled, clean them out using a vacuum or hole brush or compressed air.

4. Thread the nut to the top of the anchor to protect the threads and tap it with a hammer into the hole until it hits bottom.

5. Before placing the plate and wall on the anchors, roll out sill gasket, rubber or plastic to keep the wood from sitting on the concrete. It protects the wood from water damage.

You could run a bead or two of polyurethane caulking to go under the plate instead or use pressure treated lumber. Some builders use all three methods.

6. Drill matching spaced holes in the plate, and then stand the wall onto the anchors.

7. Place the washer and nut and use a wrench to tighten. As you tighten the nut to hold the plate down, it expands the bottom of the bolt in the concrete and grips to hold the shed secure.

 

Retrofit

If your shed is already built on a concrete pad, which is also its floor, but has no anchors holding it to the concrete, you can install ½” x 7” concrete expansion anchors.

If the bottom plate is still exposed, the process is the same as if it were a new construction on an existing pad, with one additional step.

Image courtesy of Oregonstate.edu

1. For a ½” x 7” concrete expansion anchor would be to use a 5/8” wood bit to drill the holes in the plate. Set a guide or tape the bit so you leave 1/32” of wood before the concrete. Concrete will dull the wood bit.

2. Use a ½” concrete bit in a hammer drill to bore the holes 4½” into the concrete.

3. Clean out the holes.

5. Tap in the concrete expansion anchors through the wood into the concrete.

5. Tighten the nuts using a socket wrench.

Anchor Shed Built on Skids to Slab

There are several ways to anchor a shed on skids to an existing concrete pad. The same methods will work for a shed with a joist or joist and beam floor on the slab.

The anchor plates or T-straps are attached to the rim joist or beam instead of the skid.

Option 1 – Foundation Anchor Plate

To anchor a shed built on skids you can use No products found.. These plates are heavy-duty 7 gauge galvanized steel and weigh about 4 pounds each.

1. At the side of both ends of each outside skid expose the edge of the concrete pad.

2. Place the plate with the large holes down against the concrete and skid side. The large holes should be at least 3” below the top of the concrete. Mark the holes on the concrete and skid.

3. Use a hammer drill with the appropriate sized bit for the concrete expansion anchor to drill the holes in the concrete. Clean the holes of dust and debris.

4. Use a drill with the smaller diameter wood bit than the lag screw being used to drill pilot holes.

5. Tap the concrete expansion anchors into the holes, mount the anchor plate, put on the washer and nut and tighten with a socket wrench.

6. Use a socket wrench to drive the lag screws into the skids. Your woodshed on skids is anchored to the concrete pad but is still movable by removing the anchors.

Option 2 – T-Strap

T-straps are another way to anchor a shed built on skids to a concrete pad. 6”x5” T-straps are light 14 gauge galvanized steel and weigh about 4 ounces each.

1. Expose the concrete at both ends of each skid.

2. Place the T-strap upside down, so the two holes are at least 1½” below the top of the concrete slab. Mark the holes on the concrete and skid.

3. Use a hammer drill and appropriate sized bit to drill the holes in the concrete. You could use concrete expansion anchors or Tapcon hex-head screws. Clean the holes when finished.

4. Use a drill with a wood bit to drill a pilot hole in the skid.

5. Tap in the concrete expansion anchors and secure the T-strap with the washer and nut. If using Tapcon screws, align the T-strap with the holes, place a washer on the Tapcon and use a socket or ratchet drill to tighten.

6. Attach the T-strap to the skid with a lag screw or a Tapcon or nails. The shed on skids is now secured to the concrete.

Option 3 – Tapcon Screws

Tapcon screws are available in different lengths and diameters. It is best to use ¼” Tapcon hex-head screws with a washer added when securing anchor plates to concrete.

Tapcon screws can be used instead of concrete expansion anchors to secure the base plate of a shed built directly on a concrete pad.

Use ¼” Tapcons that are at least 3” long every 16” between the studs. The bottom plate is 1½” thick, so the 3” Tapcon the same distance into the concrete.

1. Using a hammer drill with an appropriate diameter and length concrete bit to drill through the bottom plate into the concrete. Tapcon screws often come with a bit. Clean the holes as best as you can.

2. Use a socket wrench or drill with a hex-head driver, to drive the Tapcon screws through the bottom plate into the concrete. Don’t over tighten as that can strip the thread in the concrete or snap the screw.

Sheds secured with anchor plates or T-straps and attached with Tapcon screws or concrete expansion anchors should withstand most wind forces.

However, if a tornado strolls through your backyard, the concrete pad may be all that’s left.

 

Tie Down Shed Lifted off the Concrete Slab with Concrete Blocks

A shed that sits on concrete blocks, which rest on a concrete pad, can be anchored to the concrete pad. If it is a shed on skids, or beam and joist, or a simple joist floor, the process to connect the shed to the pad is the same.

You’ll need ½” concrete expansion anchors or bolt wedge anchor, galvanized steel straps, and ½” structural-connector screws to connect each corner to the pad.

1. Use a hammer drill with a ½” concrete bit to make the holes for the concrete expansion bolts. Clean out the holes.The holes should line up with what you plan to connect to on the shed.

The joist next to the rim joist is best, but the rim joist will work if you cannot reach the other. The inside joist is protected from weather more and will hold the beam or skids to tie down the shed.

2. Thread the nut onto the top of the anchor bolt to protect the threads and hammer it into the hole. Ensure there is enough thread exposed for the strap and the washer and nut.

3. Bend the strap 1” from the hole for the anchor. Cut the strap to length if too long; it should go up the side of the joist to the floor.

Predrill holes for the structural-connector screws spaced as needed. One screw is good, two is better.

4. Remove the nut, place the strap on the anchor bolt, then the washer and thread the nut back on. Tighten the nut to the concrete using a wrench.

5. Use a socket wrench to drive the ½” structural-connector screws and attach the strap to the joist. You may want to drill a pilot hole if you can.

 

How to Anchor a Plastic Shed to a Concrete Pad

Plastic sheds are light and often held together with ½” sheet metal screws. To anchor them to a concrete pad you need ½” concrete expansion or wedge-bolt at each corner.

A galvanized or plastic coated cable or strap long enough to go over the shed from one anchor to another. Plus a way to connect the cable to the anchor bolts; a loop or ring nut for a ½” bolt would work.

1. Use a hammer drill with a ½” concrete bit to drill a hole in the pad at each corner. Clean out the holes and tap the bolts in with a hammer.

2. Use a wrench to tighten the nut against the concrete or a temporary block of wood to expand the anchor into the concrete. Thread the loop or ring nut on if using a cable, or attach one end of the strap and rethread the washer and nut.

3. Some plastic shed roofs are designed for a cable or tie down straps and have a built-in channel for them. If they don’t, then you need to go over the roof.

4. The metal strap connects to the anchors with the nuts. A cable connects to the loop or ring by threading through the ring and connecting to itself with wire rope fittings. The cable or strap should be pulled tight to prevent the shed from moving.

 

How to Secure a Metal Shed to Concrete

Metal sheds can be secured to a concrete pad at each corner from within, or from outside. A metal strap or cable can be run up the wall, between the roof metal and the metal rafters, and back down the opposite wall to secure the shed and roof to the concrete pad.

1. Use a hammer drill and ½” concrete bit to drill a hole at each corner. If anchoring inside, use a steel bit to make a 5/8” hole in the corner of the steel floor, and drill into the concrete.

Clean out the 4 holes and tap in the concrete expansion or wedge bolts. Use the nuts to tighten the bolts so they expand and grip the concrete.

2. Connect the strap or cable to an anchor and thread it through the roof structure and down to the other anchor. Pull tight and secure. The shed is tied down to the concrete.

 

How to Anchor a Shed to Pavers

When a shed is attached to a solid concrete pad, the tonnage of the concrete is the anchor. A concrete paver weighs between 50 and 100 pounds, so anchoring your shed to one is a waste of time and effort. If you can lift it, so can the wind.

If you don’t want a permanent anchor, then use an auger or corkscrew style ground or earth anchor. You can buy shed ground anchor kit at most building stores.

For the best location for the anchors, measure in about 12” on the long sides from each corner and close to the wall. If the ground is dry or hard, use water to soften it.

1. Hammer the point of the auger anchor as far into the ground as you can so it will dig in as you turn it.

2. Use a pipe or wrench through the eye of the auger to twist it into the ground. The farther it is in the ground, the better an anchor it is. Ideally, you want just the eye above the ground.

3. Connect the shed to the auger anchors using cable and cable connectors.

Recommended products:

• 4-Piece Earth Anchor Kit with 4 Clamp-on Wire Tie-downs
• Liberty Outdoor Folding Ring Spiral Ground Anchor

 

Anchoring Sheds Built on Other Types of Foundations

Solid Concrete Blocks, Deck Blocks, Gravel Pad and Timber Frame, Skid Foundations

To anchor an existing shed that doesn’t sit on a concrete pad, you can use ground or earth anchors, the more permanent concrete pier anchor, or mobile home tie-downs.

The most permanent anchor after a concrete pad is the concrete pier. They should be located a foot in from the corners on the long sides and as close to the walls as possible; under the shed is good too. For longer sheds add one in the middle between the corners.

1. Dig or drill 12” holes to below the frost line.

2. Form with a sonotube and fill with concrete. Insert anchor bolts before the concrete sets. The top of the anchor can be above ground, below ground, or at ground level.

3. Use a loop or ring nut if using cables to secure your shed to the anchors. If using a plate or a strap instead of cable, then use a washer and nut to connect to the anchor bolt.

Mobile home tie-downs are a cross between the ground anchor and the concrete pier. They are designed to go over the top of a single-wide trailer and underneath a double-wide.

You could use one per side on a small shed, or 2 or 3 per side on a larger shed. They could be used to anchor almost any shed.

1. Dig a 12” diameter hole about a foot deep near the end most pier at each corner, as close to the wall as possible; underneath if there’s space. If it is a large shed, you’ll want another set of holes midway along the long wall.

2. Screw the auger anchor into the middle of the hole so the top is above the top of the hole.

3. Once all shed anchors are in place, mix and pour concrete into the holes and let set.

4. Connect the ratchet top to the auger anchor shaft. Thread the metal strap between the skid, beam or joist and the shed. It can thread through to the other corner ratchet, or back to itself. Cut off the excess and tighten the ratchets.

Recommended products:

• Tie Down Engineering 59090N Iron Root Double Head Anchor
• Tie Down Engineering 59155 Certified Galvanized Strapping - 37'
• Tie down MRA59110 Cross Drive Anchor

 

How to Tie Down Shed to Concrete Piers

When building a new shed on concrete piers lay out the pier plan based on the shed design. The holes for the concrete piers should be centered under the posts, beams, or skids used to support the shed floor.

1. Dig or drill the piling holes below the frost line. Tamp the bottom of the holes and fill with 6”s of gravel for drainage.

2. Insert a sonotube in each hole, plumb level and secure. The top should be a minimum of 4” or 5” above the ground to be above standing water. It can be higher if using the piers to create a level foundation.

3. Fill with concrete, ensuring piers stay level. Before the concrete hardens, insert anchor bolts or brackets. Align the brackets or bolts according to the layout plan.

4. Attach the beam to the anchors and lay out the joists. Use plates or joist hangers to connect the joists to the beams, creating a continuous line securing the shed to the concrete pier anchors.

Source QUIKRETE

If a shed already sits on concrete piers but is not anchored to the pier, then concrete expansion or bolt wedge anchors can be inserted into holes drilled close to the shed base or foundation. Holdowns or anchor plates or straps could then be used to secure the shed to the pier.

Source Ask the Builder

Recommended products:

• Simpson Strong Tie Predeflected Holdown Anchor
• Simpson Strong Tie PB66 Post Base

Anchoring Shed to Post and Beam Foundation

A post and beam foundation is similar to concrete pier construction, except instead of concrete,  wooden 6”x6” or 8”x8” are used. It is set into the ground, leveled and plumbed, and then concrete poured into the hole to secure the post.

To anchor the beams to the posts, use anchor plates and straps to prevent wind lift. Using brackets and joist hangers to connect the joists to the beams will effectively connect the floor structure to the anchored posts. This is a good way to stop high winds from moving your shed.

Screw Piles

Galvanized screw piles are steel posts with a screw end. A special attachment on an excavator screws the piles into the ground to the frost line. You can use a hand-held power driver instead of the excavator.

The piles have flat U brackets that the beams sit in and bolts that attach the beams to the screw piles. It is a quick way to make a level foundation for a shed, and an effective anchor too.

 

How to Tie Down a Rubbermaid Shed

Rubbermaid sheds come in a variety of sizes. It is a heavier construction than a plastic shed and has steel ribs that the panels connect to.

The steel ribs also connect with the steel rafters that the roof panels attach to. Although heavier construction, they still need anchoring.

Shed tie-down kits are available that use auger style anchors that screw into the ground at each corner. Cables or straps go over the roof or in the rafter channel and connect to anchors on each side of the shed. If you move the shed, you just dig the anchors out of the ground and use at the next location.

Dig holes, form and pour concrete piles at each corner and the middle if a long shed. Use anchor bolts with a loop or ring top and inserted into the concrete before it hardens.

Connect a cable or strap to the ring or loop to anchor the shed. This is a permanent anchor.

Another method involves cutting holes in the bottom of the shed beside the steel ribs. Remove a couple of feet of soil, either through the hole or from outside digging under the shed.

Fill the holes with concrete and insert a metal strap bent in an L or a J at the bottom. When the concrete cures, push the strap against the steel rib and drill several holes.

Use bolts or self-tapping screws to attach the strap to the rib. Your shed is permanently tied down.

 

How to Anchor a Metal Shed

Metal sheds are available in different sizes and are usually heavier than plastic sheds. You can attach the shed to a concrete piling at each corner from outside.

A metal strap or cable run up the wall, between the roof metal and the metal rafters, and back down the opposite wall and secured to a ring or loop bolt in the concrete piling anchors the shed and roof.

Auger style tie down spikes are also a good way to secure the steel shed to the ground. Screw the auger into the ground at the 4 corners instead of the concrete pilings.

Cables or straps connect to the loop on the auger and thread up the walls and between the roof and the rafters to anchor the shed. The augers can be dug up and moved if you move your shed.

Source YouTube

 

Conclusion

If you want your shed to stay where you put it, then you’d better tie it down. You built the shed to protect your belongings; shouldn’t you protect your shed too?

There will always be wind. If you anchor your garden shed, it has a better chance of protecting everything in it.

Hope you enjoyed the article and found it informative. If you have extra information or any questions, please let us know.

Your comments are appreciated. If you know someone who worried about the wind damaging their shed, share with them if you liked it.