Can I Build a Second-Story Deck Over My Patio?

Building an Elevated Deck Over an Existing Patio

One of the most common questions we receive is whether a second-story deck can be built on top of an existing patio slab. The short answer: it depends on several factors.

Why Patio Slabs Usually Aren't Suitable

Most residential patio slabs are designed for ground-level use only:

• Thickness – Typically 4 inches, not designed for point loads
• Reinforcement – Often minimal or no rebar
• Foundation – May not extend below frost line
• Compaction – Soil preparation may be inadequate for structural loads

What's Required Instead

To build an elevated deck, you'll typically need:

1. Independent footings – New concrete piers extending below frost line
2. Structural posts – Properly sized for height and load
3. Engineering – May require stamped plans for second-story structures
4. Additional permits – Elevated decks have stricter requirements

Options for Your Property

Depending on your situation, we might recommend:

• Remove the patio and install proper footings in its place
• Cut through the patio to install new footings
• Build adjacent to the patio with a freestanding structure
• Evaluate for ground-level deck directly on the existing slab

Code Requirements for Elevated Decks

Second-story decks in Wake County require:

• Guard rails at least 36 inches high (42 inches for some jurisdictions)
• Balusters spaced no more than 4 inches apart
• Stairs with proper rise/run ratios
• Multiple inspections during construction

Let Us Evaluate Your Site

Every property is different. Our team provides free consultations to assess your existing patio, discuss options, and recommend the best approach for your elevated deck project.