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RoofCostLab

2026 project cost

Replace Roof Underlayment Cost

$1,374 to $2,024 for 1,000 sq ft, or about $1.37–$2.02 per sq ft. That covers 5 material line items and about 8 labor hours.

Estimate your replace roof underlayment project

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sq ft

Estimated total

$1,374 – $2,024

materials + labor

Materials
Labor
Per sq ft

What the materials cost

Quantities for 1,000 sq ft, including a 12% waste allowance.

Material Qty Cost
2-in x 10-ft Black Galvanized steel Drip Edge 112.01 EA $573 – $809
Synthetic Roof Underlayment 1120 SF $202 – $392
2-in Smooth Shank Electro-galvanized Roofing Nails 3817 -Per Box 1.13 BOX $45 – $64
Roofing Sealant 2.25 TUBE $18 – $34
Single Bead Butyl Tape Sealant 50-Feet Roof Seam Tape 1.13 EA $6 – $8

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How long it takes

  1. 1

    Remove Old Roofing Materials 4-6 hours

    Carefully strip away shingles and existing underlayment from the roof in your area, disposing of debris according to local guidelines. Inspect decking for damage.

  2. 2

    Inspect and Repair Roof Deck 2-3 hours

    Examine the exposed roof deck for rot or damage. Replace or repair any compromised sections to ensure a solid base for new underlayment in your area.

  3. 3

    Install New Underlayment 4-6 hours

    Roll out and secure new underlayment across the roof surface, overlapping seams and fastening according to manufacturer instructions for your area weather conditions.

  4. 4

    Reinstall Roofing Materials 6-8 hours

    Install new shingles or roofing material over the underlayment, ensuring proper alignment and secure attachment to meet your area building codes.

Frequently asked questions

Do I need a permit to replace roof underlayment in your area?

In most of your area, replace roof underlayment is treated as maintenance rather than structural work, so no building permit is required. A permit does become necessary if the job expands into replacing the roof covering or the decking beneath it. Confirm with your local building department in your area before work starts.

Is replace roof underlayment covered by a home warranty or insurance?

Routine work like this is normally treated as owner maintenance, so home warranties and insurance policies rarely cover it. Insurance generally applies only when the damage comes from a sudden covered event such as a storm. Check your policy terms for your area before assuming coverage.

What is roof underlayment and why is it important?

Roof underlayment is a protective layer installed between the roof deck and the shingles. It acts as a barrier against moisture, providing an extra layer of protection for your home in your area.

How long does it take to replace roof underlayment in your area?

Replacing roof underlayment in your area typically takes a few days, depending on the size and complexity of the roof. Weather conditions and the availability of materials can also affect the timeline.

Can I replace roof underlayment myself or should I hire a professional?

While it is possible to replace roof underlayment yourself, hiring a professional in your area is recommended. Professionals have the expertise to ensure the job is done correctly and in compliance with local building codes.

Calculators for this project