8 Mistakes to Avoid When Building an Outdoor Deck
When building an outdoor deck, everyone makes mistakes. If you search the internet for “deck building mistakes” you will find many interesting and not-so-interesting articles and videos of deck crashes. These can be directly linked to mistakes in the building. While it’s easy to build an outdoor deck on a home improvement show, installing a deck is a big job. There are many things to consider in terms of planning and safety, and things to avoid during the process. This article shows you how to avoid making some of the most common mistakes when building a deck.
Table of Contents
Mistake 1: Putting a sill plate on the house
Most of the time, half of the weight of the deck is supported by a sill plate attached to the side of the house. The sill plate becomes a beam, and this single board can hold thousands of pounds of weight. This weight must be placed on the supporting part of the house, not on the exterior siding or the outer skin of the house. In addition, the sill plate needs to be attached to the house so it does not come apart and cause problems or cause the house to collapse.
Here are some of the most common mistakes people make when attaching deck ledger boards:
- Putting ledger boards on the house
- Using bolts with square heads to hold the ledger board in place
- Using fasteners that won’t stand up to rust and corrosion
Nails are not a good choice for fasteners because they are not strong enough to hold all the weight. In addition, they are usually easy to remove. If a group of people starts dancing on a flimsy deck, the deck could fall off the house. This sudden occurrence can cause serious injuries to people on the deck.
People often think that square-headed nuts are a good way to attach sill plates. However, this is not a good idea. Because you can’t see what’s behind the siding or bricks of the house, how do you know if they’re biting into the solid wood behind the exterior skin of the house? Also, if the person putting in the square head bolts is too rough and twists them too much, they can damage the wood and make the square head bolts much less useful.
Copper is used to treating a lot of new wood. Copper prevents the wood from rotting. Copper and iron are both types of metal, but they are not the same. On outdoor decks, all bolts and structural links are made of iron or steel. When water is added to copper and iron, an electrochemical process occurs. Steel or iron will rust and decompose as a result.
To prevent this corrosive chemical mixture, all fasteners, especially those used for sill plates, must be made of stainless steel, or have a very thick layer of hot-dipped double galvanizing. When you build a deck near the ocean, salt spray can get into the deck. The salt in the ocean water can also make rusting worse, so fasteners made of stainless steel must be used.
The best way to secure ledger boards in a house is to use bolts. These fasteners go all the way through the ledge boards on the outside of the house and then through the horizontal joists or band plates on the inside. Place a washer and nut on the machine thread at the end of the through bolt. The sill plate will not come loose and fall to the floor until the inside structural joists or band plates are pulled together.
The best way to attach the sill plates is with special anchors that attach to the sides of the deck joists. Each joist in the house has a similar anchor bolted to its side. These anchors fit into these anchors. A galvanized threaded rod runs through the sill plate to connect these two supports. Structural engineers recommend that you use this method to ensure that the sill plate does not come off the house or come loose.
Mistake 2: Attaching the crossbeam to the support post in the wrong way
You can build an outdoor deck without posts, using only joists secured to beams of concrete. This is by far the safest deck. However, most outdoor decks are at least four feet off the ground. On most decks, the joist rests on a beam at the end away from the house. This beam must then be supported by posts that extend all the way to the ground. Think of these posts as the legs of a table or chair. If the beam is not properly attached to the posts, it will turn and fall. This error can cause the deck to collapse.
You can stop the beam from moving away from the post in two ways. Most beams are made of two 2×10 or 2×12. The end of the beam is about 3 and 1/4 inches wide. You can use a 6×6 post and cut an L-shaped notch in it. The beam sits on this sill for solid support, with 2-inch posts going all the way to the top of the beam. Then, use through bolts to connect the transom to this long wooden tongue. This is a tried and true method.
The second method is to purchase structural metal frame connectors. These connectors have been tested to create a strong connection between the post and beam as allowed. You can choose from many different styles and patterns. Make sure that the connectors you will use are made for the dimensions of the wood you will be using. Since metal connections are subject to moisture, make sure they are corrosion-resistant.
Mistake 3: Using the wrong deck fasteners
Problems can easily occur if you use the wrong deck fasteners. You’ve probably seen workers using nail guns to shoot nails through the wood veneer. Using a nail gun isn’t a bad idea, but it depends on the corrosion resistance of the nails. However, if you decide to secure your deck, make sure you use deck fasteners that won’t rust.
First, you must decide if nails are the best choice. Over time, nails begin to loosen from the joists. Most of the time, screws work better than nails, and they don’t come loose as often.
Before you choose which fasteners to use, ask the company that makes your flooring what they think is best. Most likely, you will need some sort of nail or screw. Keep in mind that if you use the wrong fasteners, the warranty on the decking material may no longer be valid.
You should also know that most nails that fit into a nail gun have a thin layer of coated metal on the outside. These nails will begin to rust in a very short period of time. In this way, galvanized nails tend to break down quickly.
The best material for nuts and bolts is stainless steel. Next, you should choose screws that have been galvanized twice and then heated.
It is also a good idea to cover the top of the deck joists with special joist tape. This makes it more difficult for water to get through the holes in the bolts. This tape is easy to use and will help hold the wood tightly to the joists and protect them.
Mistake 4: Spacing deck joists incorrectly
There is a lot more space between decks than you think. This is especially true if your outdoor deck is constructed of composite decking material. the distance between composite decking joists is important because it keeps the deck from sinking over time.
Before you start building your outdoor deck, read the installation instructions provided by the deck manufacturer. If you want to put the deck on a diagonal, you may be surprised to find that the space between the joists needs to be 12 inches in the middle. This is because when you measure perpendicular to the joists, the distance is shorter than when you measure horizontally.
You should also pay close attention to the floor standards for the load-bearing surfaces under the bottom end of each floor. On some composite decking, each floor must have 1.5 inches of the load-bearing area at each end. Only 3/4 inch of space can be left between two floors on a single board.
Mistake 5: No railing or improper railing installation
Installing railings on outdoor decks will keep people safe. Building codes specify how strong railings need to be. Most decks at ground level do not require railings, but decks that are two feet or more above ground level should have railings.
Also, deck railings are often not considered in the design of outdoor decks, which is a mistake in itself. Railings are probably one of the most visible parts of outdoor space, so it’s important to consider your options early. Railings are not only useful, but they are also a part of your home’s design, just like windows. They should look great in your home and show off your style.
Installing railings on your deck requires a lot of skill. Don’t use square-headed nuts. Remember, they become levers when you push or lean on the top of the railing or the posts that hold the railing in place. When many people push on a beam at the same time, the force can be so strong that a square-headed bolt will pull a regular nail out of the wood faster than a pry bar.
Handrails and posts can only be attached to the base of the deck with through-hole bolts. A better method is to use special holding anchors that are bolted to the sides of the deck boards and then attached to the posts with through bolts. This creates a very strong connection.
Nails should never be used to install handrails. Over time, nails will lose their strength to hold things in place. If the nails rust or lose their grip, pieces of the handrail can inadvertently fall off the post.
Pay close attention to what the building code says about deck railings. Remember, the building code is a list of things that must at least be done. You can always come up with something better than what is specified in the code. Think ahead and make a plan. Think about someone leaning on the railing you’re going to build next weekend, 20 years from now. Will the deck railing still be as strong as it was when you made it?
Mistake 6: Poor Deck Post Foundations
The deck post footing, also called the “floor foundation,” is where the weight of the deck is distributed on the ground below the deck. Keep in mind that different soils have very different strengths. Some soils are so weak that a stick will go through them. Some soils are so hard that they are almost as strong as a rock.
If you don’t know much about soil and how strong it is, you should talk to your local building inspector before you start digging a foundation for your outdoor deck. Here are some things you should ask the inspector
- How big of a hole is needed?
- What is the width or size of the hole?
- How deep should the foundation be?
- Should reinforcing steel be used to strengthen the foundation?
- Should the base protrude from the ground, and if so, how high should it be?
Remember, the bottom of the deck foundation needs to be below the frost line in your area. Frost waves are real and can cause the deck to rise at least 4 inches. The size of the bottom of the deck is something that needs to be known. You want the weight of the deck posts to be spread out on the ground as much as possible.
The bottom of most decks should be at least 8 inches thick, and posts made of cast concrete should sit on top of the bottom and be at least 6 inches in diameter. It would be nice to have 8 or 10 inches.
Steel rebar is cheap and can give a lot of strength to foundations and piers. You can be sure it will work. Don’t put deck posts made of treated wood in the ground. Treated wood posts are very susceptible to rotting or being eaten by bugs. Place the base of your outdoor deck about 6 inches above the ground so that the wooden posts are not near any wet soil or standing water.
Mistake 7: Choosing the wrong deck trim material
Once you start making plans for your outdoor deck, you’ll need to compare all the materials you can use. The deck material you choose will determine how you build it. Don’t assume that all decks are installed in the same way.
Today, there are two main types of mainstream outdoor deck materials.
- Natural heat wood
- composite decking materials
Different materials have different advantages and disadvantages. When deciding between wood and composite decking, it may be helpful to make a list of pros and cons.
In most cases, natural wood is easy to cut and splice. However, some rainforest lumber is so hard that you must drill a hole for each fastener. Decks made from wood need to be cleaned and sealed at regular intervals. Using an approved organic oxygen bleach is the best way to clean a wood deck. Never use chlorine bleach, as it breaks down the lignin that keeps the wood fibers in place. When bleach is used, the wood will also lose its original color.
Composite decking requires very little maintenance and does not require the sealing of the laminate. You may only need to lightly scrub it with mild soapy water once or twice a year to ensure its beautiful appearance.
Installing composite decking boards is very easy. It is as easy to cut as wood decking while not creating cracks or warping. The best composite decking materials have a hidden fastener system that ensures that the decking is set up correctly and will look good for a long time. Using these fasteners takes more time and work than using a nail gun, but the benefits are worth it.
Whichever type of flooring you choose, don’t forget to put safety tape on the wooden beams and joists of the substructure. With these tapes, water can’t get through the holes the fasteners make in the logs. Over time, water will cause the wood to crack and the screws holding it in place will come off.
Mistake 8: Not getting a building permit
In the United States, almost every city or town requires a permit for a deck. In some states, when you require a permit, the engineer must also stamp the building plans. Before you start making plans for your outdoor deck, you should ask the building department about this.
You need to make sure that your deck plans are safe and built according to the rules for your area. Building a home without a permit can also make it difficult to sell if a potential buyer or home inspector finds that the local building office has no record of the permit.
Obtaining a permit and following the rules for building decks in your area will help avoid accidents and other problems. For example, you may find out early on that your deck does not comply with the rules in your area. Can you imagine spending all that money and time making a new deck without a permit, only to find out you had to tear it down or make it smaller? Because you didn’t get the right permits? Every year, this happens to people who want to do it themselves. Don’t give it a chance!
Also, if you are part of a homeowners group, you need to know what their rules are. Associations can limit the types of materials you can use and allow you to use certain fencing and railing styles. Do your homework. Seek advice. Talk to friends who have already been through this situation.