To support the framing, a remodeling company will often use load-bearing posts for decks and overheads, and each post must be placed in a base. A footing is typically a hole in the ground that extends below the frost line and is filled with concrete. Different building codes, climates and soil conditions may allow alternative footings, such as concrete or tamped earth piers.
The type and dimensions of the footing depends on the deck’s height, the types of materials you plan to use, how deep the ground is freezing and the soil’s load-bearing capacity.
Footings must support two types of charges inherent in any structure: dead and live charges. A deck’s dead load is the weight of all its permanent elements – posts, beams, framing, decking, planting, stairs and railings – before putting on it transient items (snow, furniture and people). Most building codes will require a deck to be built to support a dead load of 10 pounds per square foot and a 40 pounds live load per square foot. This means that footings installed by your home improvement company must be constructed to support a total weight of 50 pounds per square foot along with the other support elements.
The consistency of the soil varies and hence their capacity to support a load. Loose soils have minimal load-bearing capacity and may require more or greater bases than heavy clay or compacted soils. Local codes take into account local soil conditions, so before you start planning your deck, it is important to contact the building department. Local codes may specify different spacings or methods of construction than those shown in standard span tables.
The freezing and thawing of the soil causes it to expand and contract in cold climates, sometimes dramatically. If the posts are set incorrectly, any soil movement will be transferred to the posts and above them the deck structure, shifting or cracking portions of the deck and causing severe structural damage. It is important to make sure that your home improvement company or contractor takes note of this.
Look no further than Up and Above Contractors for your decking needs. We only use top-tier manufacturers and the finest quality materials to ensure that your project will last for years to come. Call us today at (973) 531-4225 to schedule a free consultation with New Jersey’s top roofing company.