How Much It Costs to Replace Rotted Roof Wood

Replacing rotted wood on a roof is a common repair that protects structure, prevents leaks, and extends roof life. This article explains typical costs, factors that drive pricing, repair options, and guidance for budgeting and hiring professionals. Readers will learn how to estimate expenses and choose the right repair approach based on the extent of rot and local market conditions.

Repair Type	Typical Cost Range	Typical Scope
Spot Plywood Replacement	$150 – $600	Small patches, 1–3 sheets
Partial Deck Replacement	$600 – $2,500	Multiple rafters/sections
Full Deck Replacement	$2,500 – $7,000+	Entire roof deck, large homes
Structural Joist/Rafter Repair	$500 – $5,000+	Damaged framing or ledger repairs

Contractors inspect by walking the roof, probing suspect areas with a screwdriver, and checking the attic for stains, mold, or soft spots. Moisture meters, infrared cameras, and exploratory roof cuts are used for accurate assessment when rot is concealed.

Cost Factors That Affect Replacement Price

Several variables determine how much to replace rotted wood on roof. These factors explain why estimates vary widely and help homeowners interpret bids.

• Extent Of Damage: Spot repairs cost far less than full deck replacement.
• Type Of Wood And Decking: Plywood, OSB, or plank decking have different prices and labor needs.
• Structural Repairs: Replacing rafters or joists increases costs significantly.
• Roof Pitch And Accessibility: Steeper or multi-level roofs are pricier to work on.
• Roof Size And Complexity: Multiple valleys, dormers, or penetrations add labor time.
• Material And Labor Rates: Local labor costs and material availability affect final price.
• Permit And Disposal Fees: Municipal permits or dumpster rental may add to the bill.

Typical Cost Breakdown

This breakdown helps translate scope into dollars so homeowners can plan realistically. Prices shown are national averages and will vary by region and season.

Item	Unit Cost Range
Plywood/OSB Sheathing (per sheet)	$15 – $45
Rafter Repair/Replacement (labor + materials)	$150 – $1,200 per member
Shingle Replacement (per square)	$100 – $300 per square
Flashing Replacement	$50 – $500
Labor (roofing contractor)	$45 – $90 per hour
Debris Disposal / Dumpster	$200 – $600

Repair Options And When To Use Them

Repair choice depends on rot severity. Homeowners should evaluate short-term fixes versus long-term solutions to avoid repeated repairs.

Spot Plywood Patch

Best for small sections of rot localized to a few sheets. This involves cutting out damaged areas and replacing with new plywood, then re-shingling. Labor is relatively quick and low cost.

Partial Deck Replacement

Used when multiple areas show damage or when sheathing has widespread delamination. Contractors remove sections of deck and install new sheathing, addressing any underlying vent or flashing problems.

Full Deck Replacement

Recommended when the deck is extensively compromised or old OSB/plywood is failing across the roof. This is most cost-effective when combined with a roof replacement since shingles are already removed.

Structural Framing Repair

When rafters, trusses, or joists rot, they require reinforcement or replacement. Structural repairs are specialized and often require engineered bracing or sistering to restore load capacity.

How To Estimate Replacement Costs For Your Roof

A simple process helps produce a ballpark estimate: measure roof area, inspect damage, choose repair type, and apply local cost multipliers. Homeowners can use square footage and sheet counts to convert scope into likely costs.

1. Measure roof area in square feet and convert to squares (1 square = 100 sq ft).
2. Count how many 4×8 sheathing sheets are affected (1 sheet ≈ 32 sq ft).
3. Multiply sheet count by material cost per sheet and add labor per sheet estimate ($50–$150 depending on complexity).
4. Add flashing, shingles, and disposal fees, then factor in structural repair allowances if needed.

Examples: Cost Scenarios

These scenarios illustrate typical ranges so homeowners can compare to contractor quotes. Prices assume average regional labor and common asphalt shingle materials.

• Small Spot Repair: One or two sheets replaced, minor flashing work, re-shingling: $150–$600.
• Moderate Partial Deck Repair: 5–20 sheets replaced, small structural fixes, new underlayment: $600–$2,500.
• Major Deck Replacement: Entire deck removed and re-sheathed on a 1,500–2,500 sq ft roof: $2,500–$7,000+.
• Framing Repair With Deck Work: Rafter replacement plus deck patches: $1,000–$5,000+ depending on structural complexity.

When To Repair Versus Replace The Roof

Decisions balance cost, roof age, and future plans. Spot and partial repairs are reasonable for newer roofs with limited rot, while older roofs near end-of-life or with widespread decay usually warrant a full roof replacement.

DIY Considerations And Risks

DIY plywood patching is feasible for experienced homeowners with safe roof access. However, structural repairs, working at heights, and warranty implications make professional work advisable in many cases. Improper repairs can lead to ongoing leaks and higher costs later.

How To Hire A Contractor And Compare Bids

Select licensed, insured roofing contractors with local references and written estimates. Compare line-item bids that separate materials, labor, structural work, and disposal so apples-to-apples comparisons are possible.

• Ask for photos of the damage and a clear scope of work.
• Verify contractor insurance and licensing where required.
• Request warranty details for both labor and materials.
• Get multiple bids and check online reviews and Better Business Bureau ratings.

Ways To Reduce Costs

Smart choices can lower replacement costs without compromising longevity. Scheduling repairs in shoulder seasons, consolidating work, and addressing ventilation or flashing issues proactively can prevent future rot and save money.

• Fix gutters and ventilation before replacing decking.
• Bundle deck work with roof replacement when shingles are due for replacement.
• Obtain multiple bids and negotiate material sourcing.
• Consider higher-quality underlayment to reduce future leaks.

Signs To Watch For After Repairs

Post-repair monitoring ensures the problem is resolved. Homeowners should watch for return of stains, soft spots in the attic, new shingle damage, or recurring mold growth. Prompt follow-up with the contractor is essential if symptoms recur.

Key Takeaways For Budgeting

Budget realistically by assuming some level of hidden damage when rot is visible. Set aside a contingency of 10–30% above the contractor estimate to cover unexpected structural repairs discovered during work.

Action	Suggested Budget Approach
Spot Repair	Estimate low-to-mid range and add 10% contingency
Partial Deck	Use mid-range prices with 15% contingency
Full Deck/Structural	Plan for higher-end estimates and 20–30% contingency

Resources And Next Steps

Homeowners should schedule a professional inspection when any attic stains, soft spots, or roof leaks appear. Getting at least three detailed bids and documenting damage with photos helps ensure fair pricing and a durable repair outcome.

For further guidance, consult local building codes, review manufacturer warranty documents for shingles and underlayment, and contact trusted local roofing professionals for in-person assessments.