Does a deck need a foundation?

Decks are supported by foundations, which transfer loads to the soil. The system comprises concrete footings, deck posts, anchors and post caps. Footings are concrete pads that typically rest at least 12 inches below the ground. In some areas, they extend deeper based on frost lines or when working on a steep grade.

Can you build a deck without a foundation?

Building your dream deck without footings

Instead of using footings, adding a level of gravel will give you the drainage aspect you are looking for. You can then add a frame of wood that anchors in concrete blocks that sit in the gravel, creating your new deck.

Can a deck be built without footings?

You can also build a deck without footings. A deck without footings might be appropriate if it is a low deck platform. Deck blocks, made of concrete or heavy-duty plastic, are strong enough to hold these kinds of deck platforms. Low decks don't need footings because they are close to the ground.

Can a deck be built directly on the ground?

Yes, you can build a deck directly on the ground, but with some conditions. A deck on the ground must be built with ground-contact wood, and the substructure needs to be adapted for minimal height. Even though technically a ground level deck is elevated up to 24”, here we will discuss decks built less than 8” high.

Is deck considered a foundation?

Whether you call them deck piers, caissons, footings, or something else, as far as the International Building Code is concerned they are all essentially the same: isolated foundation systems that have to transfer loads imposed from above to the earth below.

What Type of Post Base Connection Should I Use While Building a Deck?

Do freestanding decks need footings?

According to the main code provision for footings, the only requirement for building a deck that is freestanding is that it must have a minimum footing depth of 12 inches below the undisturbed ground surface. There is no need to extend a footing below the frost line, as is required for standard decks.

When building a deck What are the requirements?

Can I use deck pier blocks instead of footings?

Pier blocks can be used instead of footings for a ground-level deck not requiring permits. Piers blocks can also be used if the frost level depth is less then the height of the pier block. Allowing you to set the pier block below the frost level on stable ground.

How do you prepare the ground under a deck?

A layer of crushed gravel, with or without plastic or weed barrier cloth, is the best choice for using under a deck. It sheds moisture instead of absorbing it, keeps the area under the deck drier, and won't decay.

How low to the ground can a deck be?

There is no standard height for a “grade-level” deck—the maximum measurement from grade to the deck surface could be 6 inches, 12 inches, 24 inches, or more. But generally speaking, I apply the term to decks that are up to 30 inches above grade, since guardrails are required for any decks that are higher than that.

Can you build a deck without putting posts in the ground?

Yes. It's possible to build a deck without digging holes. This type of deck is called a floating deck, and it sits right on top of the ground without any posts or support areas that you'd dig down into the ground [to secure].

Do deck blocks need to be buried?

Simply placing them on the ground or on a poured concrete pad a few inches deep usually isn't enough to comply with codes — they must be set at least 12 inches deep in undisturbed soil. However, concrete deck blocks can be used without restriction for a freestanding deck that's not attached to your house.

Will deck blocks sink?

The deck blocks can sink if the soil under them erodes for some reason or the weight is unevenly distributed. That's why it's a good idea to use more than less.

What is a floating deck?

A floating deck is a deck that isn't attached to a building and they “float” above the ground. Generally, floating decks are low to the ground and don't require handrails or even staircases. They are sometimes called “grade-level” or “freestanding” decks because they're built just above the ground level, or grade.

Does decking need drainage?

A deck allows you to relax and entertain outside, but without proper drainage, it's possible for water to pool underneath. This can create a breeding ground for mosquitoes, mold and bacteria. If you have water standing under your deck after the rain, choose a drainage system that works for you.

Should I put concrete under deck?

Adding a patio under a deck with pavers or natural stone is an optimal solution to just pouring a concrete pad. It's going to make your space that much more usable while also being much more aesthetically appealing. Patio pavers with a drainage solution are also ideal for keeping water away from your home.

What do you put under deck blocks?

Sand or gravel under the blocks works best because these materials don't change with seasonal freeze-and-thaw cycles. They allow water to seep away in the fall, eliminating frost-related heaving in the winter. Heavy clay soils, on the other hand, can rise and fall substantially because they hold so much moisture.

How deep should a deck footing be?

By code, the bottom of a footing must be at least 12 inches deep and below the local frostline—whichever is deeper—and bear on stable, undisturbed soil that is free of organic matter. And the code requires a minimum compressive strength of 2,500 psi for the concrete.

How much does it cost to build a 20x20 deck?

The average homeowner spends $2,200 to build a 10x10 foot deck, $6,160 to build a 14x20 deck, and $8,800 to build a 20x20 deck. The cost to build a deck with pressure-treated wood, hardwood, or composite is about $25 per square foot, for both materials and installation.