Outdoor-space glossary

Plain-language definitions for common planning and construction terms.

Attached deck

A deck structurally connected to a building, commonly through a ledger or other designed connection.

Base course

Compacted material beneath a patio surface that distributes load and supports drainage.

Beam

A structural member supporting joists or other loads.

Cantilever

A portion extending beyond its support within approved limits.

Control joint

A planned line intended to manage where concrete cracking occurs.

Flashing

Material arranged to direct water away from vulnerable joints and assemblies.

Guard

A barrier intended to reduce falls at an elevated edge.

Handrail

A graspable rail intended to support users on stairs or ramps.

Ledger

A structural board used to connect an attached deck to building framing.

Permeable paving

A surface system designed to let water pass through openings into a prepared base.

Subgrade

The prepared soil supporting a pavement or slab system.

Wet-service condition

A structural design condition accounting for wood exposed to elevated moisture.