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CertainTeed Underlayment & Deck Repair: The Jacksonville Owner’s Guide
CertainTeed underlayment and roof deck repair in Jacksonville typically runs between $450 and $1,800 installed, with underlayment replacement on a standard 3-tab or architectural shingle roof falling between $1.10 and $2.40 per square foot including tear-off of the old layer. We stock CertainTeed-compatible underlayment rolls and decking materials on our trucks, and most underlayment-only jobs are completed the same day we start. The way Jacksonville homeowners usually find out they need this repair is a ceiling stain after a hard afternoon downpour, or a roofer’s note during a routine inspection that the decking feels soft underfoot.
Key Takeaways
- CertainTeed warranties often require a specific underlayment type to stay valid, so matching matters.
- Florida heat and June-to-September humidity shorten underlayment life compared to northern climates.
- We write the price before work starts and it does not change unless we uncover hidden deck rot, which we’ll show you in photos before proceeding.
- We’re an independent Jacksonville roofing company, not affiliated with CertainTeed, but we install and repair their systems daily.
Styles & brands we work with






Which CertainTeed Models This Applies To
CertainTeed’s underlayment lineup splits into two families: synthetic and felt. The synthetic rolls, sold under names like RoofRunner and DiamondDeck, come in widths of 36, 42, and 48 inches and are what most Jacksonville homes built after 2010 have under their shingles. The felt products, like CertainTeed’s 15 lb. and 30 lb. base sheets, are the older standard. Your roofer’s invoice or the permit from Duval County will usually list which one was installed. The compatibility gotcha few people know: CertainTeed’s shingle warranties for lines like Landmark and XT 25 require a synthetic underlayment for the full warranty term. Bury a 15 lb. felt under those shingles and the warranty paperwork quietly expires. We’ll match the original spec, or we’ll upgrade you to a synthetic if your current deck repair means we’re already pulling the old layer up anyway.
Signs Your CertainTeed Underlayment & Deck Repair Is Failing
- Water stains on ceilings or walls after a storm. Underlayment is the waterproof layer under shingles. If it’s torn, cracked, or was installed with exposed fasteners, water finds the seam. In Jacksonville’s summer thunderstorms, a pinhole leak shows up fast.
- Shingles lifting or flapping in certain spots. Nails backed out of soft decking and the underlayment underneath is now exposed to UV. That section degrades within months.
- Soft spots or a spongy feel when walked on. That’s decking failure. In Florida’s humidity, OSB decking swells and loses strength. We see this most on older Riverside and Murray Hill homes where attic ventilation was never upgraded.
- Visible daylight through the attic boards. Underlayment has worn through and decking has gaps. This is a deck repair, not just an underlayment swap.
- Granules in gutters plus damp insulation. The shingles are shedding and the underlayment is doing all the waterproofing work. In Jacksonville, that’s a countdown clock, not a maybe-fix.
See the difference
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After
Before
After
Before
AfterReplacement Cost & What’s Included
In Jacksonville, a straight forward underlayment replacement on a 2,000 square foot roof runs between $2,200 and $4,800. A partial repair covering one roof slope is usually $450 to $1,200. Decking repair adds $75 to $110 per 4×8 sheet replaced, depending on whether it’s OSB or plywood match. Every quote from Birchbark Roofing Jacksonville includes the tear-off of the old underlayment, the new CertainTeed-compatible roll or sheet, the decking replacement if needed, all fasteners, and full clean-up. You’ll get one written price before we pull a single shingle. Erik Lindgren and our crew will walk the roof with you first, point out what we’re seeing, and put the number in your hand. The 365-Day Done Right Promise covers the work from ridge to eave.
DIY or Call Us?
You can safely check your own attic for daylight through the boards, and you can inspect your ceilings after a storm. That’s where DIY should stop. Underlayment and deck repair means pulling shingles off in the Florida sun, walking on a roof that may have soft decking underneath, and sometimes working with a nail gun at height. If the decking is compromised, the risk isn’t the underlayment, it’s you standing on it. We use fall protection, we’ve done this on hundreds of Jacksonville roofs, and we’ll bring the materials with us. If you want to see the damage before deciding, call (904) 604-7914 and we’ll come look with you. You’ll have the price in writing before we touch a shingle.
FAQs
CertainTeed synthetic underlayment typically lasts 18 to 25 years in Jacksonville’s climate, while felt underlayment lasts 12 to 18 years. Florida’s UV exposure and high attic heat are the two big killers. If your roof is 15 years old and got a felt install, you’re near the end. Call (904) 604-7914 and we’ll inspect it for free.
Yes, small sections of torn or cracked underlayment can be patched and re-secured if the surrounding area is sound. That’s typically a $450 to $900 repair on one slope. If the tear is larger than a few feet or decking is soft beneath it, replacement is more cost-effective. We’ll tell you which one you actually need, not which one makes us more money.
Most underlayment-only replacements are done in one day. If we’re replacing decking sheets too, plan for one to two days depending on how many sheets are compromised and how steep the roof sections are. We’ll give you a schedule before we start and stick to it.
We stock CertainTeed-compatible synthetic rolls and felt in the most common widths on our trucks, along with OSB and plywood decking sheets. If your job calls for a specialty CertainTeed product we don’t have on board, we order it and schedule you within the week. We also work with GAF and Owens Corning underlayments when that’s the better match for your existing roof system.
Call Birchbark Roofing Jacksonville for Your CertainTeed Underlayment & Deck Repair
If your ceiling is staining, your attic is showing daylight, or a roofer already told you the decking needs attention, call (904) 604-7914 for a free estimate. We’ll walk the roof with you, show you what we’re seeing, and give you one written number before any work starts. We’re a Jacksonville roofing company first, not a sales team in another city. Erik and the crew live here, work here, and we clean up like it’s our own home before we leave.
Written by Erik Lindgren, Owner, Birchbark Roofing Jacksonville at Birchbark Roofing Jacksonville, serving Jacksonville and nearby areas.