Roof Redecking: Homeowner's Guide 2026
- Teresa
- Jun 6
- 8 min read
Roof replacements are common after 20-30 years, but it’s important to not overlook replacing your decking as well.
In this comprehensive homeowner’s guide to roof redecking, we will review:
What Is A Roof Deck
What Is Redecking
Common Roof Deck Replacement Signs
Minnesota Building Codes
Replacement Cost
Insurance Coverage
The Replacement Process
For a quick overview, check out the FAQs and the glossary here.
If you are considering replacing your Minnesota roof, connect with PEI today to schedule a free inspection.
What Is Roof Decking?
The decking on your roof, also known as sheathing, is generally a flat layer of wood directly attached to your roof rafters or trusses. This flat surface serves as the foundation for all other roofing materials, like your shingle of choice.
What Is Redecking?
Redecking your roof is the process of repairing or overlaying the old decking with sheet decking, either plywood or oriented strand board (OSB). OSB is most commonly used to stay more budget-friendly, but plywood is known for its durability and moisture resistance.
What Are The Common Signs Your Roof Decking Needs Replacement?
Wood decking, although durable, cannot always withstand all weather conditions and damage. Over time, the decking needs to be replaced along with the new shingles, providing the best nailable surface, strength, and durability.
Water Damage
Prolonged moisture exposure causes the wood fibers to break down. The decking feels soft or spongy, losing structural strength to be a nailable surface. We can determine this damage by meticulously walking across the roof and feeling for soft spots and gaining attic access to see the backside of the decking.
Perforated Decking
Perforated decking is caused by too many nails driven into the decking after multiple roof replacements and can be another reason the decking is no longer suitable.
Sagging Roof
A sagging roof can occur from long-term water damage, heavy snow, or prolonged heat exposure that sags the decking or rafters. The decking should be replaced, along with any other areas of structural damage.
Building Code
Your state might have updated their building codes since the last time your roof was completed, voiding the current installation. Because of this, your contractor will update the decking in order to meet regulatory requirements.
Extensive Storm or Pest Damage
Extensive storm or pest damage can shatter decking and cause severe structural damage.
These signs can happen to older or newer roofs, depending on the area’s weather conditions or installation techniques. Normally, we expect to verify all roofs, especially before the 1960s, but we’ve redecked a new home originally with OSB because of water damage, poor attic ventilation, or ice dams in the winter.
It’s important to schedule an inspection and consider potential replacement of the roof and its decking after 20-30 years or after any significant damage.
What is the Minnesota Building Code For Redecking My Roof?
When you hire a contractor to replace your roof, they must comply with your state’s building codes to pass home inspection. If they fail, your contractor is liable.
In Minnesota, reroofing guidelines are followed in Section R905 of the Minnesota Residential Code.
A Summary Of The Minnesota Residential Code For Reroofing
R905.2.1 Sheathing Requirements
Asphalt shingles shall be fastened to solidly sheathed decks or 1-inch thick nominal wood boards
Building codes require existing decking to be a maximum of ⅛” spacing at the ends and sides and no spaces or gaps between the deck boards greater than ¼”. Any gaps or holes greater than code require a redeck.
Redecking is often necessary for homes built before 1960 because of plank decking. If there is more than ⅛” of space between your planks, the roof decking must be brought up to code per the shingle manufacturer’s installation instructions. Shingle manufacturers updated their shingle warranties over the years to require a smooth, continuous surface.
How Much Does A Roof Redeck Cost?
For a standard, normal condition roof decking replacement, the cost may range between $5,000-10,000 based on the size of the roof, the steepness, accessibility, flashing, and current labor cost.
Will Insurance Cover The Cost To Redeck My Roof?
If you are starting a home insurance claim because of damage, like hail, wind, water, or tree damage, your insurance will determine if the decking is caused by any of these sudden, accidental events. It’s recommended to be prepared to pay the cost of a redeck if your insurance does not cover it. However, you should expect your contractor to address the situation with the insurance company, by providing photos and explanation for the necessity of redecking.
Can You Tell The Insurance Company I Need A Redeck Before You Start My Roof Replacement?
Yes. If we have access to the attic and roof, we can often determine if your decking needs to be replaced. However, prior to roof tear off, your insurance company might not provide confirmation the redeck is covered until the entire decking is visible.
If I Can’t Afford A Redeck, Can I Skip It?
No. If your contractor determines that your house does not meet building code because of rotten or damaged wood, a sagging roof, or ⅛” or greater spacing between plank decking, you cannot skip a redeck.
Skipping A Redeck Will Cause The Following:
Void Warranties
Shingle manufacturers will not honor product warranties if shingles are installed on degraded or improperly spaced decking.
Unsecured Shingles
Shingles need to be secured to the decking. If the decking is rotted or has holes and gaps, the shingles cannot be properly secured. This may lead to shingles blowing off.
Failed Inspection
Most cities require a permit for roof replacements. After the roof is installed, a local building inspector will fail the roof if the decking is not following building code requirements.
You Can Avoid Redecking Because Of The Following:
Solid Decking
If your roof was built with plank decking but is in good condition, no holes or gaps, and does not exceed building code requirements for spacing, you should not need a redeck.
Plywood or OSB Sheathing
If your roof has solid plywood or OSB sheathing, with no signs of water damage and is structurally sound, you will not need a redeck.
Ask For A Cheaper Solution
If a redeck is necessary but you cannot afford it, ask your contractor about a partial redeck or financial assistance to help ease the cost.
What Is The Process To Redeck A Roof?
Generally, if you're looking to get a free estimate on the cost to replace your roof, an inspection of your roof and attic will be scheduled. Depending on your roof accessibility, we can determine if a redeck will be necessary.
Home insurance claims follow a similar process; however, the redeck will be reviewed by both the contractor and your insurance company.
Review the dropdown menu below to see the steps towards redecking your roof.
Inspection
During the initial inspection for a standard roof, we will inspect your roof and attic, home history, including any major damage, and take photos
Retail Estimate
Your retail estimate is created based on your roof size and accessories. Generally, decking replacement is not quoted unless it’s needed.
Insurance Estimate
An insurance estimate is created based on the damage found and will be supported with the photos and documentation we provide to your insurance company. Because the insurance process is more complicated, the estimate and your final cost is determined by your insurance company, deductible, and damage.
Removing Old Roofing Material
The existing shingles or tile, underlayment, and roof accessories are removed. If the original decking is severely damaged or broken, the decking is also removed completely.
Installing New Decking
Plywood or OSB is installed on top of existing decking or rafters/trusses.
Installing New Roofing Material
New underlayment, shingles, and accessories are installed
Roof Redeck FAQs
What is the purpose of redecking a roof?
The purpose of re-decking a roof is to restore the foundation for your roofing system, create a smooth, continuous surface, and abide by your city’s building codes.
Does my insurance cover redecks?
Generally speaking, homeowners insurance covers redecking if the damage is caused by a sudden, accidental event, like a severe storm, fire, or falling tree. It is also generally covered if the building codes have changed and the existing decking, while in good physical condition, does not meet the current code requirements. The claim is most commonly denied if redecking is needed to repair normal wear and tear, wood rot, or lack of maintenance. Connect with your insurance agent for specialized answers or start a free inspection with our PEI team to discuss what’s best for you.
What are the signs you need to redeck your roof?
Common signs your decking needs to be replaced can include water damage, wood rot, storm damage, gradual deterioration, or insufficient installation. You can examine the underside of the roof decking from the attic or by carefully walking across the roof to feel for soft spots. We recommend scheduling a free inspection to examine your roof.
Is there a way to tell if a deck needs to be re-roofed prior to signing a contract?
Generally speaking, yes, but not always. It’s helpful to have proper access to both the attic and the roof.
Can I get quoted what it would cost to redeck?
For standard, normal condition roof decking replacement, the cost may range between $5,000-10,000 based on the size of the roof and the current cost of labor. If your roof decking needs to be replaced, your contractor can provide a more specific estimate.
What if I can’t afford a redeck?
If you can’t afford the cost of a full redeck, you can ask your contractor about partial redecks to target the most problematic areas of your roof. Otherwise, see if your contractor offers a payment plan or financial assistance.
Can I skip a redeck if I can’t afford it?
In most cases, a redeck is mandatory in order to meet building code, pass the home inspection, and be eligible for shingle manufacturer warranty. Skipping a redeck during the initial roof replacement only creates more work and cost in the future.
What is the difference between plank and sheet decking?
Many older homes built before the 1960s used plank decking. Individual wooden boards are nailed side-by-side to the rafters or trusses. This standard decking did add more character to the attic or ceiling, with exposed beams and high durability, but it’s labor-intensive to install and costs three times more than sheet decking. While not common in new construction, you’ll still see plank decking used.
Glossary
Decking Also known as sheathing, decking is the first flat layer of wood connected to the roof trusses or rafters
Redecking The process of adding a new layer of roofing material, either plywood or OSB, on top of existing decking to provide a stronger foundation for a new roof.
Plywood Thin sheets of wood veneer glued together to make a strong, highly stable engineered wood that prevents shrinking, splitting, or warping.
Oriented Strand Board (OSB) A compressed board of glued wood strands, usually made from poplar or aspen trees, in a specific orientation to be strong and rigid.
Plank Decking Standard decking prior to the mid-20th century using wooden boards nailed side-by-side across the rafters or trusses of a roof.
Normal, Standard Roof By PEI definition, a standard roof is accessible and walkable. Attic access is available.
Ready For An Inspection?
If you’re in Minnesota, reach out to Professional Exteriors Inc. (PEI) for a free estimate.
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