Ground Preparation & Drainage

Proper ground preparation beneath a deck is critical for long-term performance, moisture management, and overall aesthetics. This page provides a comprehensive breakdown of our ground prep process, including materials, installation techniques, and best practices for a durable, low-maintenance foundation.

Weed Barrier Installation

To prevent weed growth and reduce maintenance, we install a heavy-duty plastic weed barrier beneath the deck.

Key Features:

Durable, long-lasting material that resists tearing and UV degradation
Prevents unwanted vegetation from growing through the deck footprint
Provides a clean surface for gravel or other ground coverings

Installation Details:

Barrier is laid directly on prepared soil and cut precisely around posts and footings
Overlaps and seams are secured to prevent gaps
Optional anchoring stakes are used in areas with loose soil or slope

Gravel Base: 6A Washed Stone

Once the barrier is in place, we install a gravel base using 6A washed stone, a clean, crushed gravel ranging from 3/8" to 1".

Why 6A Washed Stone?

Drainage: Coarse, free-draining material prevents standing water beneath the deck
Durability: Maintains stability and does not compact tightly like other gravels
Aesthetics: Attractive natural colors create a polished base, especially for partially visible areas
Free-Draining: “Washed” means fine particles (fines) are removed, allowing water to flow freely

Installation Notes:

Gravel depth is calculated based on deck height and site conditions
Level and slightly compacted to create a stable walking and storage surface
Stone can be paired with underlayment for extra weed control or moisture protection

Landscape Perimeter

A 4×4 timber perimeter can be installed around the gravel base to:

Contain stone and prevent shifting
Provide a defined, clean edge between the deck and surrounding landscaping
Create a finished, intentional appearance beneath the deck

Placement Considerations:

Typically included with gravel/underlayment installations
May not be required if the deck includes skirting or fascia to grade, as these naturally contain the gravel

Installation Details:

Timber perimeter is cut to precise dimensions for clean corners and level lines
Secured into grade with stakes or anchors to maintain stability
Gaps are left where necessary to allow drainage and prevent water pooling

Combined Benefits of the System

When installed together, these ground prep components provide:

Low-maintenance foundation: Limits weeds, mud, and erosion
Enhanced drainage: Water flows freely, reducing risk of rot or standing water under the deck
Durability: Supports long-term performance of both the deck frame and surface materials
Visual appeal: Creates a polished, finished look, especially for elevated or partially visible decks

Installation Notes & Considerations

Ground prep is strongly recommended for elevated decks and low-clearance decks.
The combination of weed barrier, gravel, and perimeter ensures a stable, long-lasting base.
All installations are adapted to site-specific conditions, including slope, drainage, and soil type.
Homeowners can choose to combine this with under-deck skirting, wrapped posts, or access doors for a fully finished appearance.