How to Install Lap Siding Guide for Eastern Washington Homeowners & Contractors

Essential Tools and Materials for Eastern Washington Installations

Before starting any lap siding project in Eastern Washington, assembling the right tools and materials prevents costly delays and ensures professional results. Our extreme climate demands specific equipment and materials that might not be necessary in milder regions.

Required Tools for Professional Results

Cutting and Measuring Equipment:

Circular saw with carbide-tipped blade (minimum 40 teeth for smooth cuts)
Miter saw for precise angle cuts and butt joints
Jigsaw for curved cuts around fixtures
4-foot and 8-foot levels for maintaining straight courses
Chalk line for layout work
Speed square and framing square for accurate measurements
Tape measures (25-foot minimum)

Installation Tools:

Pneumatic nailer (15-gauge finish nailer or siding nailer)
Air compressor with minimum 6-gallon tank
Hammer for hand-nailing and adjustments
Nail sets for countersinking finish nails
Caulk gun for sealing gaps
Utility knife with extra blades

Safety Equipment (Critical in Eastern Washington’s Conditions):

Safety glasses and dust masks (essential when cutting fiber-cement)
Work gloves with good grip for handling materials in cold weather
Sturdy ladder or scaffolding system rated for wind conditions
Fall protection harness for two-story installations
First aid kit accessible on job site

Safety Warning: Wind conditions around Spokane Valley and elevated areas near Kettle Falls can change rapidly. Never work on ladders or scaffolding when sustained winds exceed 15 mph or gusts reach 25 mph. Eastern Washington’s sudden weather changes make continuous monitoring essential.

Climate-Specific Material Requirements

Fasteners for Temperature Extremes:

6d galvanized ring shank nails (2-inch minimum length)
Stainless steel nails for coastal exposure areas or high-humidity microclimates
Never use aluminum or standard galvanized nails—they fail in our temperature swings
Corrosion-resistant screws for trim attachment (2.5-inch minimum)

Weather Protection Materials:

High-quality housewrap (minimum 10 perms) like Tyvek CommercialWrap
Drainage mat systems for enhanced moisture protection
Self-adhering membrane for window and door openings
Kick-out flashing and step flashing (minimum 0.019-inch aluminum)
Quality acrylic-latex caulk rated for temperature extremes (-40°F to 180°F)

Material Selection for Eastern Washington Climate

Choosing the right siding material for Eastern Washington’s extreme conditions requires balancing initial cost, long-term maintenance, fire resistance, and thermal performance. Each material responds differently to our temperature swings, low humidity, and occasional severe weather.

Fiber-Cement Siding: The Regional Favorite

Performance in Eastern Washington:
James Hardie and similar fiber-cement products excel in our climate extremes. These materials handle temperature swings from -20°F to 105°F without the expansion and contraction issues common with other materials. The low moisture content (typically 6-8%) matches our regional humidity levels.

Specifications for Our Region:

Maximum board width: 12 inches (narrower widths perform better in temperature extremes)
Minimum overlap: 1-1/4 inches (increase to 1-1/2 inches in high-wind areas)
Expansion gaps: 1/8 inch at butt joints, 3/16 inch at trim
Meets ASTM C1186 standards and ICC-ES reports
Class A fire rating crucial for Eastern Washington wildfire zones

Cost Analysis:
Expect $4.50-6.50 per square foot for materials, with premium textures reaching $7.50. Professional installation adds $3-5 per square foot. While initially expensive, 30-50 year warranties and minimal maintenance make this cost-effective long-term.

Maintenance Schedule:

Annual inspection for caulk and paint condition
Repainting every 12-15 years (Eastern Washington’s intense UV requires quality paint)
Caulk touch-ups every 5-7 years at expansion joints
Power washing every 2-3 years to remove dust and pollen

Engineered Wood: Balanced Performance

LP SmartSide Performance:
Engineered wood products offer excellent durability when properly installed. The SmartGuard process provides moisture and insect resistance important in our region. These products handle both horizontal and vertical installations, though horizontal remains standard.

Installation Requirements:

Specific spacer systems required for expansion gaps
Strict nailing schedules every 16 inches on center maximum
All field cuts must be primed within 4 hours (critical in our dry air)
Minimum 6-inch clearance from grade (8 inches in snow-prone areas)

Cost Considerations:
Material costs range $3.50-5.00 per square foot. Installation runs $2.50-4.00 per square foot professionally. Factor in annual maintenance costs of $0.15-0.25 per square foot for optimal performance.

Natural Cedar: Traditional Choice with Higher Maintenance

Western Red Cedar Considerations:
Cedar provides unmatched natural beauty but requires commitment to maintenance in Eastern Washington’s dry climate. Proper installation techniques become critical for longevity.

Climate-Specific Requirements:

1/8-inch expansion gaps minimum (increase to 3/16 inch for boards over 8 inches wide)
Back-priming all boards recommended to prevent cupping
Stainless steel or hot-dipped galvanized fasteners only
Annual treatment with water-repellent preservative

Wildfire Considerations:
Natural cedar doesn’t meet Class A fire ratings required in some Eastern Washington areas. Check local fire marshal requirements before specifying cedar siding. Consider fire-retardant treatments where required, though these add $1-2 per square foot to costs.

Composite Siding: Modern Performance

Everlast and Similar Products:
Composite materials like Everlast Composite Siding offer excellent weather resistance but typically limit installation to horizontal orientation only. These products work well in our climate but require specific installation techniques.

Installation Specifications:

1/4-inch gaps at all trim pieces and corners
Nailing patterns every 8 inches with specific nail placement
Starter strips positioned 3-1/2 inches minimum above grade
Cannot be installed vertically per manufacturer specifications

Performance Data:
Composite siding typically carries 25-30 year warranties with minimal maintenance requirements. Costs range $5.50-7.50 per square foot for materials, with installation adding $3-4 per square foot.

Material	Cost/Sq Ft (Installed)	Fire Rating	Warranty	Maintenance Level	Best For Eastern WA
Fiber-Cement	$7.50-11.50	Class A	30-50 years	Low	All areas, especially fire-prone zones
Engineered Wood	$6.00-9.00	Class B	5-30 years	Medium	Suburban areas with regular maintenance
Cedar	$8.00-12.00	Class C	None typically	High	Custom homes, areas without fire restrictions
Composite	$8.50-11.50	Class A	25-30 years	Low	Modern homes, low-maintenance applications

Pre-Installation Preparation: Foundation for Success

Proper preparation determines whether your siding installation will last decades or require costly repairs within years. Eastern Washington’s challenging environment makes thorough prep work non-negotiable.

Structural Assessment and Preparation

Sheathing Requirements:
Your walls need solid structural backing before siding installation begins. OSB or plywood sheathing provides necessary fastener penetration and creates the flat surface essential for professional results.

Minimum sheathing thickness: 7/16 inch for 16-inch on-center framing, 19/32 inch for 24-inch on-center framing. In Eastern Washington’s wind conditions, especially around elevated areas near Colville and Kettle Falls, consider upgrading to 5/8-inch sheathing for enhanced structural performance.

Wall Flatness Correction:
Older Eastern Washington homes often have wall irregularities requiring correction. Use a 4-foot level to check wall flatness—variations exceeding 1/4 inch over 4 feet require furring strip correction.

Install 1×3 furring strips vertically over studs, shimming as needed to create a flat plane. This step is critical for professional appearance and weather protection. Budget an additional $0.75-1.25 per square foot for furring strip installation.

Weather-Resistive Barrier Installation

WRB Selection for Eastern Washington:
While we receive less rainfall than western Washington, when moisture events occur—from snowmelt or summer storms—they can be intense. Install high-quality housewrap or advanced drainage mat systems even in our dry climate.

Critical Clearances for Regional Conditions

Grade and Foundation Clearances:
Eastern Washington’s alkaline soils and occasional heavy snow require specific clearance planning. Maintain minimum 6 inches between siding and soil or landscaping—increase to 8 inches in areas with regular snow accumulation like higher elevations around Kettle Falls.

Foundation clearance: 1 inch minimum above foundation walls, 2 inches preferred. This prevents splash-back during rare heavy rains and allows inspection access for pest control—carpenter ants remain a concern in our region’s wooded areas.

Roof Clearances and Flashing:
Maintain 2-inch minimum clearance from roof planes with proper step flashing installation. Install kick-out flashing wherever rooflines meet siding—this detail becomes critical during rapid snowmelt when large volumes of water must be directed away from walls.

Window and Door Preparation

Flashing Installation:
Proper window flashing prevents the moisture intrusion problems we see in Eastern Washington homes, especially during spring snowmelt periods.

Installation sequence:

Install sill flashing extending 6 inches beyond window frame each side
Install side flashing up sides of window frame
Install head flashing over window frame and over side flashing
Seal all flashing joints with appropriate sealants
Install WRB over head flashing but not over sill flashing

Trim Preparation:
Use minimum 1-inch thick trim materials like TruWood products for substantial appearance and durability. Pre-prime all trim pieces before installation, paying special attention to end cuts which absorb moisture rapidly in our dry climate.

Step-by-Step Installation Process

Professional lap siding installation follows a systematic approach that ensures both appearance and performance. Each step builds on the previous work, making careful attention to detail essential throughout the process.

Layout and Starting Course

Establishing Level Starting Point:
Begin by establishing a level reference line around the building perimeter. Use a water level or laser level to mark points 3-1/2 to 4 inches above foundation or grade line. In snow-prone areas like higher elevations around Colville, consider raising this to 4-1/2 inches.

Snap chalk lines connecting these points. Double-check levelness—errors compound rapidly with horizontal siding. A 1/4-inch error at the start becomes increasingly obvious as courses progress upward.

Starter Strip Installation:
Install starter strip along chalk line using 6d galvanized ring shank nails every 16 inches into framing members. The starter strip creates the proper angle for your first siding course and ensures consistent reveal throughout the installation.

Butt joints in starter strips should occur over framing members with 1/8-inch expansion gap. Seal joints with appropriate caulk after installation.

First Course Installation

Board Preparation:
Before installation, check each board for defects and pre-plan your layout to minimize waste and avoid short pieces at corners. Boards shorter than 2 feet look unprofessional and create potential moisture entry points.

Prime all field cuts immediately—Eastern Washington’s dry air causes rapid moisture loss that can lead to checking and splitting within hours of cutting.

Installation Sequence:
Start first course at the most visible corner, typically the front of the house. Position board so it rests on starter strip with proper overlap—1-1/4 inches minimum for most products.

Nail through flat portion of board approximately 1 inch above overlap line. Never nail through overlapping areas as this prevents natural expansion and contraction movement.

Continuing Course Installation

Maintaining Level and Straight Lines:
Check level every 4-5 courses rather than trying to correct major problems later. Small adjustments maintain straight sight lines while major corrections create visible irregularities.

Use a string line or chalk line to maintain straight courses, especially important on long walls where slight variations become magnified.

Staggering Butt Joints:
Plan butt joints to occur over framing members when possible, and stagger them between courses for best appearance and structural performance. Avoid aligning butt joints vertically as this creates weak spots and unsightly patterns.

Maintain 1/8-inch expansion gaps at all butt joints in standard conditions, increasing to 3/16 inch for long boards or extreme exposure areas. These gaps are essential in Eastern Washington’s temperature extremes.

Managing Complex Areas

Window and Door Installations:
Use pocketed trim pieces around openings rather than trying to cut siding for tight fits. This approach provides better weather protection and accommodates seasonal movement.

Install drip caps over window and door heads before installing siding courses above openings. Ensure proper flashing integration with WRB system.

Corner Details:
For outside corners, corner boards typically perform better than mitered siding in our climate. Install corner boards first, then butt siding pieces against them with appropriate expansion gaps.

Inside corners use corner strips or caulked butt joints depending on desired appearance. Corner strips provide more forgiving installation and better long-term performance.

Upper Course and Roofline Details

Measuring and Cutting Top Courses:
Measure each top course piece individually as rafters may not be perfectly level. Plan for minimum 1-inch clearance from soffit with appropriate trim coverage.

Install continuous soffit trim before top siding course to create clean, professional appearance and proper weather protection.

Flashing Integration:
Ensure step flashing extends at least 2 inches under siding at roof intersections. Kick-out flashing at roof ends must direct water away from siding—this detail is critical during snowmelt periods.

Pro Tip: Work during moderate temperatures when possible. Extremely hot or cold conditions affect material dimensions and make handling difficult. Early morning installation during summer months avoids thermal expansion issues that complicate fitting and gapping.

Troubleshooting Eastern Washington Installation Problems

Our region presents unique challenges that can cause installation problems if not properly addressed. Understanding these issues and their solutions prevents costly callbacks and ensures long-term performance.

Temperature-Related Issues

Thermal Expansion Problems:
Problem: Siding buckling or pushing off at corners during hot summer days, particularly common when daytime temperatures exceed 95°F in Spokane Valley and surrounding areas.

Solutions:

Increase expansion gaps to 3/16 inch at trim pieces and corners
Check that siding isn’t nailed too tightly—boards must move freely
Avoid installation during extreme temperature days (above 90°F or below 40°F)
Consider narrower board widths (6-8 inches) in high-exposure areas