What is a connector? How to I protect my home from earthquakes and high winds? How do I inspect my deck? The following Q&A provides easy to understand explanations that answer these questions and more.
Barclay Simpson, founder of the company, made his first connecter – a joist hanger – in 1956. Today, Simpson Strong-Tie manufactures thousands of structural connectors, including joist hangers, hurricane ties, straps and holdowns. In addition to structural connectors, the company offers fasteners, anchor systems, shearwalls, multistory tiedown systems, and fastening tools. These products help improve the strength and safety of homes and buildings.
Structural connectors are made out of steel, and are engineered to connect and strengthen the frame of a home. Reinforcing the frame of a home with structural connectors helps the home resist damage caused by earthquakes, high winds and hurricanes. Framing materials secured with connectors are much stronger than if secured only with nails (called toe-nailing).
Connectors come in all shapes and sizes, and have a variety of names, such as joist hangers, holdowns and hurricane ties. Homeowners don't typically see connectors in their homes because they are covered up behind the walls.
Fasteners typically refer to nails, screws, bolts or anchors. Fasteners are used with connectors to attach framing materials together, such as wood, masonry and concrete.
Shearwalls are reinforced walls within a home that have been engineered to help resist the shear (racking) forces that are caused by high winds or lateral forces that are caused by earthquakes. Shearwalls are typically constructed by attaching wood sheathing and holdown connectors to a section of the wood framing along a wall. Pre-manufactured shearwalls, such as Wood and Steel Strong-Wall® shearwalls, are frequently used in homes as they come pre-assembled and ready for installation.
A continuous load path is a method of construction that uses a system of wood, metal connectors, fasteners (like nails and screws) and shearwalls to connect the structural frame of the house together. It ties the house together from the roof to the foundation. A continuous load path is important because it helps redistribute outside pressures or forces caused by earthquakes and high winds, transferring these external forces from the frame to the foundation, which is securely anchored into the ground. A home with a continuous load path is much better equipped to withstand the strong forces caused by high winds, tornadoes, hurricanes and earthquakes.
To learn more, visit Build with a Continuous Load Path.
Framing materials held together with structural connectors can withstand much stronger forces than if held together with nails. Connectors have what is called a higher load capacity than nails (see example below). In a high wind storm, for example, nails are much more likely to pull apart or pop out than a metal connector. A connection made with a metal connector can be pulled apart, but it takes much greater force to separate it than a simple toe-nailed connection. A home built with connectors is better able to resist forces from high winds and earthquakes.
According to Federal Emergency Management Agency (FEMA), 41 states are at moderate to very high risk of having an earthquake. The National Oceanic and Atmospheric Association, which tracks weather events, reports that all 48 continental U.S. states have had tornadoes. And while hurricanes typically affect coastal regions, all states are subject to high wind storms. Making sure your home is built with connectors and a continuous load path can help protect your home and your family when an unexpected weather event happens.
Depending on the size of your home, adding connectors can cost anywhere between a few hundred dollars to a couple thousand dollars. It really depends on the house and what needs to be retrofitted. Adding connectors and bracing to secure your foundation, for example, is a relatively low-cost project.
A skilled homeowner can tackle some types of retrofit projects, such as retrofitting your foundation if you have a basement or crawl space. However, in most cases, Simpson Strong-Tie highly recommends working with a qualified, professional structural engineer to perform a structural evaluation and then a licensed contractor to do the work for you. When hiring a design professional, you want to make sure they are licensed and have a good reputation. You should ask for references and check with the Better Business Bureau. It's also a good idea to understand the work that is to be done and get involved in the process, so that you can make sure the project is done right. Some good resources to review include our Seismic Retrofit Guide and the web pages Retrofitting Your Home for Earthquakes and Retrofitting Your Home for High Winds and Hurricanes.
Note: If you do plan to take on a retrofit project yourself, you'll need to first check with your local building department to find out the requirements you must follow. Often times you will need a building permit.
Building codes refer to a set of standards or regulations established and enforced by the local government that describe the minimum design and structural requirements for homes and buildings. If you're interested in knowing more about the building codes in your area, including whether building with a continuous path is required, contact your local building department.
- Uplift – wind flows over the roof of the home, creating a lifting effect.
- Racking – wind exerts horizontal pressure which can cause the home to tilt.
- Sliding – wind exerts horizontal pressure which can cause the home to slide off its foundation.
- Overturning – when the home is unable to rack or slide, wind can cause the walls to rotate off the foundation.
To learn more, visit How Wind Affects Your Home.
The best way to protect your home from high winds is to make sure it is built with a continuous load path. Many new homes are built with a continuous load path, but some are not, so it's best to have your home inspected by a professional home inspector or structural engineer who can help make that determination and recommend retrofit solutions if needed. For more information, see Retrofitting Your Home.
A continuous load path ties your house together from the roof to the foundation using a system of framing materials, metal connectors, fasteners (like nails and screws) and shearwalls. This system, which connects the roof, walls, floors and foundation together, strengthens the structural frame of the house. If your home is built with a continuous load path, it will be better equipped to resist the forces of high winds by redistributing the pressure of the wind from the exterior of your house to the frame, and then to the foundation. It's also important in high-wind areas to protect windows and other openings by installing such products as storm shutters or impact-resistant windows and wind-resistant garage doors.
- Sliding – earthquake forces can shake the house and weaken its frame, causing it to slide off the foundation.
- Racking – earthquake forces can cause the home to move or tilt from side to side.
- Overturning – earthquake forces can cause the walls of the home to lift or rotate off the foundation.
To learn more, visit How Earthquake Forces Affect a Home.
In order to resist forces from earthquakes and high winds, the frame of the house must be properly connected and secured to the foundation, which is the strongest part of the home. The walls, floors and roof also must be securely attached to the frame of the house. When all these key connections are made throughout the home, a continuous load path is created.
The best way to protect your home from an earthquake is to first make sure the frame of your home is properly attached to the foundation. If you have a basement or a crawl space underneath your home, you can see how you home is attached and determine whether you need additional connectors, anchor bolts and bracing. For more information, see our Seismic Retrofit Guide.
If possible, you also want to make sure your home has a continuous load path, which means all parts of the house – roof, walls, floors and foundation – are properly attached using metal connectors. This is a little more difficult to determine because you need to see what's behind your walls. However, a home built with a continuous load path is more likely to withstand an earthquake and stay intact because the home is better able to redistribute the earthquake forces from the frame to the foundation, which is securely anchored into the ground. If you are unsure whether your home was built with a continuous load path, you'll want to have your home inspected by a professional home inspector or structural engineer who can help make that determination and recommend retrofit solutions if needed.
Today, quality builders use structural connectors, fasteners and shearwalls when building a home. Depending on where you live in the U.S., local building codes often require the use of these products when building a home. However, for peace of mind, it's best to know for sure how your house was built even if you live in a newer home.
Simpson Strong-Tie recommends working with a licensed, qualified professional, such as a contractor, home inspector or structural engineer to evaluate your home and determine if additional reinforcement is needed. If you're buying a new home, don't be afraid to ask your builder what types of structural products are being using to reinforce your home. You'll want to make sure your home is being built with a continuous load path. (see Homeowner Checklist, What to Look for When Buying Home and Finding a Quality Builder).
- Loose connections – your deck should be sturdy; look for wobbly railings or loose stair steps
- Missing connections – your deck should be built with the proper hardware; you'll want to go underneath your deck and make sure the correct hardware (connectors) are used and check to see how your deck is connected to the side of the house – it should be bolted, not nailed
- Corrosion – hardware can corrode over time; look for signs of red rust on nails and metal connectors
- Rot – wood can rot and weaken your deck; take a hammer and tap on the wood framing of your deck, if the wood is soft (leaves an indent), it may be rotted
- Cracks – cracked wood can also weaken your deck; look for large or excessive cracking, particularly in posts and other structural framing
If you see any of these warning signs, you'll want to have your deck repaired or retrofitted immediately. In some cases, especially older decks, rebuilding your deck may be necessary. If you're not comfortable inspecting your deck yourself, hire a licensed, qualified home inspector, structural engineer or deck contractor.
Note: The most common deck failures are when the deck is not properly attached to the house and when railings are loose and give way.
To learn more, visit The 5 Warning Signs of an Unsafe Deck.
Simpson Strong-Tie recommends inspecting your deck at least once a year. A good time to do this is the beginning of spring before you and your family start using your deck regularly.
Well-built decks made out of wood should last 10-15 years with proper inspection and maintenance.
A skilled homeowner can tackle most deck repair projects. However, if you're not handy in construction, Simpson Strong-Tie highly recommends working with a qualified, professional home inspector or structural engineer to perform a structural evaluation and then a licensed contractor to do the work for you. When hiring a design professional, you want to make sure they are licensed and have a good reputation. You should ask for references and check with the Better Business Bureau. It's also a good idea to understand the work that is to be done and get involved in the process, so that you can make sure the project is done right. A good resource to review is our Deck Framing Connection Guide.
More questions? Feel free to submit your questions to Ask Simpson Strong-Tie.