The 18-Inch Rule

Principle: Maintain a clear, dry zone 12-18 inches wide around your foundation.

This zone should be:

• Free of mulch, plants, and organic debris
• Sloped away from foundation (minimum 6 inches drop over 10 feet)
• Visible for easy inspection
• Well-drained with no standing water

Acceptable materials for this zone:

• Gravel or crushed rock (3+ inches deep)
• Concrete or paver walkways
• Bare, compacted soil
• Landscape fabric under gravel

Wood Mulch Risks

Why problematic:

• Retains moisture against foundation
• Provides food source for termites
• Hides termite activity and mud tubes
• Creates ideal termite habitat

If using wood mulch:

• Keep 12-18 inches away from foundation
• Limit depth to 2-3 inches maximum
• Use larger bark chunks (decompose slower)
• Refresh annually, remove old mulch
• Monitor regularly for termite signs

Termite-Resistant Mulch Alternatives

Inorganic options (best):

• Gravel or crushed stone: No food value, good drainage, long-lasting
• Lava rock: Lightweight, decorative, excellent drainage
• Rubber mulch: Recycled tires, no food value, retains color
• Pea gravel: Attractive, affordable, easy to work with

Lower-risk organic options:

• Cedar mulch: Natural oils deter termites (temporary)
• Cypress mulch: More resistant than pine/hardwood
• Pine needles: Less attractive to termites, good drainage

Note: All organic mulches eventually decompose and can attract termites. Inorganic options are safer near foundations.

Safe Planting Distances

Minimum distances from foundation:

• Shrubs: 2-3 feet minimum
• Small trees: 5-10 feet
• Large trees: 15-20 feet
• Vines: Avoid planting against house

Why spacing matters:

• Allows air circulation (reduces moisture)
• Prevents root damage to foundation
• Maintains inspection access
• Reduces shade and dampness
• Prevents plants from touching siding

Plant Characteristics to Avoid

High-risk plants near foundation:

• Dense, moisture-loving plants: Create humid microclimates
• Plants requiring frequent watering: Increase soil moisture
• Aggressive root systems: Can crack foundations
• Vines (ivy, wisteria): Hide termite signs, trap moisture
• Bamboo: Invasive roots, moisture retention

Better Plant Choices

Characteristics to seek:

• Drought-tolerant once established
• Open, airy growth habit
• Shallow, non-invasive roots
• Native to your region (adapted to local rainfall)
• Low maintenance requirements

Examples (verify suitability for your climate):

• Ornamental grasses
• Lavender
• Rosemary
• Succulents and cacti (dry climates)
• Native wildflowers

Proper Grading

Goal: Direct water away from foundation

Requirements:

• Slope away from house: minimum 6 inches drop over first 10 feet
• No low spots or depressions near foundation
• Smooth, consistent grade
• Maintain slope even after landscaping

Check grading after:

• Heavy rain (look for pooling)
• Landscaping changes
• Soil settling (first 1-2 years after construction)
• Tree removal (roots decompose, soil settles)

Gutter & Downspout Management

Critical for termite prevention:

• Clean gutters: At least twice yearly (spring and fall)
• Extend downspouts: 4-6 feet minimum from foundation
• Use splash blocks: Direct water away from house
• Install gutter guards: Reduce debris buildup
• Check for leaks: Repair immediately

Downspout discharge options:

• Underground drain pipes to daylight
• Pop-up emitters in yard
• Rain gardens (away from foundation)
• Dry creek beds for drainage

Irrigation Best Practices

Avoid:

• Sprinklers that spray against house
• Overwatering near foundation
• Leaking irrigation lines
• Watering in evening (promotes moisture retention)

Better approaches:

• Drip irrigation (targeted watering)
• Soaker hoses (low, slow watering)
• Water in morning (allows drying)
• Direct water away from foundation
• Use timers to avoid overwatering

Living Trees

Maintenance:

• Trim branches away from house (3-5 feet clearance)
• Remove dead or dying trees promptly
• Monitor for termite activity in trees
• Keep tree bases clear of debris

Risk factors:

• Trees touching house provide termite highways
• Dead trees attract termites, then colonies spread
• Roots near foundation can create moisture issues

Stumps & Dead Wood

High priority removal:

• Tree stumps: Major termite attractants, remove or treat
• Dead roots: Can harbor colonies near foundation
• Buried wood: Old construction debris, landscape timbers
• Firewood: Store 20+ feet from house, elevated off ground

Stump removal options:

• Professional grinding (best for near-house stumps)
• Chemical stump remover (slow but effective)
• Complete excavation (expensive but thorough)
• If keeping: treat with borate, monitor regularly

Patios, Walkways & Retaining Walls

Design tips:

• Slope away from foundation
• Use concrete, pavers, or stone (not wood)
• Seal gaps where hardscape meets foundation
• Ensure proper drainage underneath
• Avoid wood landscape timbers near house

Retaining wall materials:

• Best: Concrete blocks, natural stone, poured concrete
• Acceptable: Pressure-treated timbers (if properly installed)
• Avoid: Untreated wood, railroad ties near foundation