Cedar Shake Roofing: The Pacific Northwest Classic That Requires Commitment

Everything you need to know about installing and maintaining cedar roofs in Washington's climate

---

Cedar Shakes and the Pacific Northwest

Nothing says "Pacific Northwest home" quite like a cedar shake roof. The warm, natural tones complement our evergreen landscape, and the material comes from trees that grow right here. For generations, cedar has been the premier roofing choice in Washington, Oregon, and British Columbia.

But cedar shakes demand more than other roofing materials. In our wet climate, they require consistent maintenance, fire treatment, and realistic expectations about lifespan. A well-maintained cedar roof is beautiful and can last 40+ years. A neglected one deteriorates rapidly and can become a liability.

This guide helps you decide if cedar is right for you—and how to care for it properly if you choose it.

---

Cedar Roofing Costs in Washington (2024)

Installation Pricing

Cedar Type	Cost Per Sq Ft	2,000 Sq Ft Roof	Expected Lifespan
Cedar shingles (machine-cut)	$8–$14	$16,000–$28,000	25–35 years
Cedar shakes (hand-split)	$10–$18	$20,000–$36,000	30–40 years
Premium/heavy shakes	$14–$22	$28,000–$44,000	35–45 years
Treated cedar (fire-resistant)	+$2–$4/sq ft	+$4,000–$8,000	Similar

Ongoing Maintenance Costs

Service	Frequency	Cost
Cleaning and debris removal	Annual	$200–$400
Moss treatment	Annual–biannual	$200–$400
Preservative treatment	Every 3–5 years	$500–$1,200
Fire retardant reapplication	Every 5–7 years	$600–$1,500
Spot repairs	As needed	$300–$800

True Cost of Ownership

Expense	30-Year Cost
Initial installation	$25,000 average
Maintenance (30 years)	$15,000–$25,000
Major repairs	$3,000–$8,000
Total	$43,000–$58,000

💡 Commitment Check: Cedar roofs require $500-$1,500 annually in maintenance to last. If you're not prepared for this ongoing commitment, consider composite shakes or other materials that mimic cedar's look without the upkeep.

---

Cedar Shakes vs. Cedar Shingles

Cedar Shakes — Rustic Character

What they are: Thick, hand-split pieces with rough, textured surface. Traditional craftsman look.

Characteristics:

• Thickness: 1/2" to 1-1/4"
• Rough texture on one or both sides
• Irregular, rustic appearance
• Better insulation value
• Higher cost

Cedar Shingles — Uniform Appearance

What they are: Machine-cut pieces with smooth surface. More uniform, refined look.

Characteristics:

• Thickness: 3/8" to 1/2"
• Smooth, tapered profile
• Consistent appearance
• Lower cost than shakes
• Slightly less durable

Which to Choose?

Factor	Shakes	Shingles
Aesthetic	Rustic, textured	Clean, uniform
Durability	Higher	Good
Cost	Higher	Lower
Traditional PNW look	Classic	Also appropriate
Maintenance	Similar	Similar

---

Cedar Performance in Washington Climate

The Good

Natural weather resistance:

• Cedar contains natural oils (thujaplicin) that resist rot and insects
• Dimensional stability—less warping than other woods
• Handles moisture well when maintained
• Breathes with humidity changes

Climate adaptation:

• Made FROM Pacific Northwest trees
• Proven performance in our climate for 100+ years
• Natural insulating properties

The Challenges

Moss growth — Primary concern:

• Our climate is perfect for moss
• Cedar's texture holds moisture and debris
• Moss accelerates deterioration
• Requires consistent treatment

Fire risk:

• Untreated cedar is highly flammable
• Washington Wildland-Urban Interface zones require treatment
• Insurance may require or incentivize fire treatment
• Ember resistance critical during wildfire season

Maintenance intensity:

• More demanding than composition or metal
• Neglect shortens lifespan dramatically
• Cleaning, treating, and inspecting required regularly

---

Fire Treatment Requirements

Washington Fire Code

Many Washington jurisdictions require Class A or Class B fire ratings for roofing in Wildland-Urban Interface (WUI) zones. Untreated cedar typically rates Class C (unacceptable in many areas).

Class A or B treatment required in:

• Most of Eastern Washington
• Foothill communities (Issaquah, North Bend, etc.)
• Many island communities
• Near state and national forests

Fire Treatment Options

Factory-Treated Cedar (Recommended):

• Pressure-treated with fire retardant
• Carries certification documentation
• Most insurance-acceptable option
• 10-20% cost premium over untreated
• Treatment lasts life of shake

Topical Fire Retardant:

• Applied after installation
• Must be reapplied every 5-7 years
• Less effective than pressure treatment
• May not satisfy all code requirements
• Maintenance burden

Insurance Implications

• Some insurers won't cover untreated cedar roofs
• Others require proof of fire treatment
• Premium discounts available for treated cedar
• Non-compliance may void coverage in fire loss

💡 Check Before Buying: Contact your insurance agent AND local building department BEFORE choosing cedar roofing. Understand treatment requirements upfront.

---

Installation Best Practices

Proper Installation Standards

Underlayment:

• Breathable synthetic underlayment preferred
• Cedar needs to dry from beneath
• Vapor barriers NOT recommended (trap moisture)
• Ice and water shield at eaves and valleys only

Spacing:

• 1/4" to 3/8" gap between shakes/shingles
• Allows expansion and drying
• Improper spacing = premature failure

Exposure:

• Typically 7-1/2" to 10" weather exposure
• Steeper roofs allow more exposure
• Low-slope requires less exposure

Fastening:

• Stainless steel or hot-dipped galvanized nails only
• Two nails per shake minimum
• Proper nail placement critical

Washington-Specific Requirements

• Skip sheathing vs. solid deck: Skip sheathing (spaced boards) allows drying but less common now; solid deck with breathable underlayment is standard
• Ventilation: Critical in wet climate—adequate ridge and soffit venting
• Flashing: High-quality metal flashings at all penetrations

---

Permit Requirements

When Permits Are Required

• New cedar roof installation
• Full roof replacement
• Cedar in WUI zones (fire code compliance)
• Any structural modifications

Fire Code Compliance

Many jurisdictions require:

• Proof of fire-rated material (Class A or B)
• Certification documentation from manufacturer
• Inspection of completed installation
• Fire treatment records on file

---

Maintaining Cedar Roofs in Washington

Annual Maintenance Schedule

Spring (April-May):

• Remove winter debris (branches, needles, leaves)
• Inspect for damage from winter storms
• Check flashings and valleys
• Schedule moss treatment if needed

Fall (September-October):

• Clear debris before wet season
• Apply moss treatment
• Inspect condition before winter rains
• Clean gutters thoroughly

Cleaning Methods

DO:

• Use low-pressure wash (under 1,000 PSI)
• Apply cleaning solution, let sit, rinse
• Clear debris with soft broom or blower
• Work from ridge down

DON'T:

• High-pressure wash (damages wood fibers)
• Use harsh bleach solutions
• Wire brush or aggressive scrubbing
• Walk on moss-covered shakes (slippery!)

Moss Prevention and Treatment

Prevention:

• Zinc or copper strips at ridge
• Trim overhanging branches
• Improve sunlight exposure
• Annual treatment applications

Treatment:

• Potassium-based moss killers (safer for cedar)
• Apply in dry weather
• Allow rain to wash dead moss
• May need repeat applications

Preservative Treatments

Every 3-5 years, cedar benefits from oil-based preservative treatment:

• Restores natural oils
• Improves water resistance
• Extends shake lifespan
• Maintains appearance
• Cost: $500-$1,200 per application

---

Common Cedar Roof Problems

Signs of Trouble

Issue	What to Look For	Urgency
Splitting	Visible cracks along grain	Moderate
Cupping	Shakes curling upward at edges	Moderate
Rot	Soft, punky wood; dark discoloration	High
Missing shakes	Gaps in roof surface	High
Moss damage	Lifted shakes, deteriorated edges	Moderate-High
Exposed nails	Nail heads visible through surface	Moderate

When to Repair vs. Replace

Repair:

• Damage limited to small areas
• Most shakes still in good condition
• Roof under 20 years old
• Isolated storm damage

Replace:

• Widespread deterioration
• Multiple soft/rotted areas
• More than 25-30% needs work
• Roof over 30 years with poor maintenance history

---

Cedar Alternatives

Composite Shake Shingles

What they are: Engineered products designed to look like cedar without the maintenance.

Pros:

• Cedar appearance
• 40-50 year warranty
• Class A fire rated
• No moss treatment needed
• Lower maintenance

Cons:

• Higher upfront cost than cedar
• Not "real" wood
• Some look artificial
• Less character as they age

Best Brands: DaVinci, Brava, CeDUR, EcoStar

Metal Shake Panels

What they are: Metal roofing stamped to resemble cedar shakes.

Pros:

• 50+ year lifespan
• Fire resistant
• Zero moss penetration
• Very low maintenance

Cons:

• Highest cost option
• Metal appearance close-up
• Different sound in rain

---

Questions to Ask Cedar Roofing Contractors

Experience Questions

1. How many cedar roofs have you installed in Western Washington?
2. What cedar grade do you typically install?
3. Do you install factory fire-treated shakes?
4. What fasteners do you use?
5. Can you provide 5+ references for cedar specifically?

Installation Questions

6. What underlayment do you recommend?
7. How do you handle valleys and flashings?
8. What exposure do you recommend for our roof pitch?
9. Do you install zinc strips for moss prevention?
10. How do you ensure proper shake spacing?

Warranty Questions

11. What warranty do you offer on labor?
12. What does the manufacturer warranty cover?
13. What maintenance is required to keep warranties valid?
14. Do you offer maintenance service programs?

---

Red Flags with Cedar Roofing

Warning Signs

• ❌ Recommends untreated cedar in WUI zone
• ❌ No experience with cedar specifically
• ❌ Uses electro-galvanized nails (will rust)
• ❌ Installs over non-breathable underlayment
• ❌ Can't explain fire code requirements
• ❌ No maintenance program or recommendations
• ❌ Claims "cedar maintains itself"

---

Find Verified Cedar Roofing Contractors

All cedar roofing contractors in our directory are verified for:

✅ Washington L&I registration ✅ Cedar roofing specific experience ✅ Fire treatment code knowledge ✅ Quality fastener specifications ✅ Local references available

Browse Washington Cedar Roofing Contractors →

---

Related Resources

• Roof Replacement Guide
• Moss Removal for Seattle Roofs
• Metal Roofing in Washington
• Roof Inspection Guide

---

Last updated: 2024. Prices are estimates based on Washington market rates. Cedar performance varies significantly based on maintenance quality, exposure, and microclimate conditions.