If you have a wooden deck, it is incredibly important that you know its weight limit.
Knowing how much weight your deck can hold will allow you to make decisions on what you keep on it. It will also allow you to keep people safe if you have a large party with a lot of guests.
Most decks need to be built up to the local building codes, which are usually very strict.
For the most part, as long as your deck is built to code, it will be safe. However, once you start adding things like hot tubs, it’s essential that you know the deck’s limit.
Determining Your Deck’s Weight Limit: Basic Idea
There is no one answer to the question of how much weight a deck can hold. It is highly dependent on several factors, including:
- Dead load and live load
- Joist and footing spread
- Wood type
Why Should I Know How Much Weight a Wooden Deck Can Hold?
Knowing how much weight your deck can hold is essential for safety.
Many people want to put a hot tub on their deck without knowing if the deck is rated for that kind of weight. Water is tremendously heavy and it could be unsafe
Knowing your deck’s weight limit is also crucial if you plan on having a lot of people out on it.
Dead Load Vs. Live Load
When you are thinking about your deck’s weight limit, it’s important to consider dead load and live load.
The weight limit on your deck will factor in both of these kinds of loads. A combination of the two will be your total weight limit.
Usually, the live load will account for ⅘ of the total load limit of the deck. If, for example, your deck is rated for a total load of 5,000 pounds, 4,000 of this can be live load.
Spread of the Joists and Footings
The spread of the joists and footings on your deck is essential for its load limit.
Most decks will have a joist span of 12 inches. This means that the joists are 12 inches apart from one another.
However, if your deck’s joists are 16 inches apart, the load limit will go down quite a bit. This is because the weight will not be as evenly spread among the joists.
The span of your footings will also make a difference. These are the pieces of wood and concrete that are driven into the ground that hold the deck up.
In general, if your deck is properly designed, it will have a weight limit of 50 pounds per square foot. Taking the dead load off this number means it will be 40 pounds per square foot of live load.
Type of Wood
The type of wood that is used for your deck will also have a lot to do with how much it can hold.
Softwoods like cedar will have a much lower weight limit than Ponderosa pine.
Type of Weather
It is very important that you also factor in the weather when you think about a deck’s weight limit.
If you live in an area that gets a lot of rain, this could also add to the dead load.
When wood is wet, it will weigh quite a bit more than it would when it is dry. Because of these factors, it’s important that you keep your live load well below the limit.
Frequently Asked Questions
- Can you put a pool on a deck?
You can put a pool on a deck, but it is important to know the weight limit.
You will probably have the pool supported by the actual ground below the deck. However, there will still be added weight along the rim.
- Can you build a pergola on top of a deck?
Just like with a pool, you can add a pergola to the deck, but be mindful of the weight.
You should also check with your region’s local building codes and zoning laws. Some areas may not allow these types of structures.
- Are 2x4s okay for decking?
2x4s are the standard size of deck slats and will usually be strong enough.
However, it is possible to use 4x4s if you want a little extra support. If you are going to put a hot tub or pool on the deck, 4x4s could be a good option.
By knowing what your deck’s weight limit is, you can use it safely and securely. You can also be sure that any additions will be supported.
While there’s no definite answer to a deck’s weight limit, knowing how it’s determined will help you keep it safe.