CertainTeed Underlayment & Deck Repair Nationwide

CertainTeed Underlayment & Deck Repair: The Orlando Owner’s Guide

If your CertainTeed roof is leaking or showing signs of deck rot, the problem usually lives in one of two places: the underlayment layer has failed, or the plywood decking beneath it has started to rot. In Orlando, a typical CertainTeed underlayment replacement runs $350 – $850 per roofing square (100 sq ft), and decking repair adds $2.50 – $4.50 per square foot of rotted wood replaced. Most Orlando homeowners discover the failure the hard way – a brown stain on the ceiling after a heavy afternoon thunderstorm, or granules from worn shingles piling up in the gutters after a windy week. By the time you see the stain inside, water has already traveled through the shingle layer, past the underlayment, and into the decking.

Call (850) 303-7235

Key Takeaways

• We stock CertainTeed RoofRunner and DiamondDeck underlayment on our Orlando trucks, so most deck repair jobs are completed the same day we start.
• Installed underlayment replacement in Orlando typically costs $350 – $850 per square; rotted deck replacement adds $2.50 – $4.50 per square foot.
• We’re the local independent Kingswell family company for CertainTeed owners – we are not a CertainTeed corporate entity, but we install and repair their full accessory line daily.
• Every repair comes with a written price before work starts and a written guarantee before the crew leaves the property.

Which CertainTeed Models This Applies To

CertainTeed manufactures two main underlayment lines that Orlando roofers install beneath asphalt shingles: RoofRunner (a synthetic, lightweight underlayment) and DiamondDeck (a reinforced synthetic with a slip-resistant surface). Both are compatible with the full CertainTeed shingle families – XT 25, Landmark, Landmark Pro, and Presidential Shake. The part that fails most often is not the underlayment itself, but the seam where it meets a roof penetration: a pipe boot, a skylight curb, or a valley where two roof planes meet. If you have the original roof paperwork, look for “CertainTeed” printed on the product label inside the attic or on the edge of an exposed underlayment flap near the eave. If you don’t, our Orlando crew can identify the layer by measurement – CertainTeed RoofRunner runs 48 inches wide and about 5.2 mils thick, while DiamondDeck is 48 inches wide and roughly 12 mils thick. We carry both in our local stock, plus quality aftermarket equivalents from GAF and Owens Corning that meet the same ASTM D226 Type II standard. For a CertainTeed warranty to stay intact, the replacement underlayment must meet or exceed that standard – and we’ll say plainly which option does before you spend a dollar.

Signs Your CertainTeed Underlayment & Deck Repair Is Failing

• Ceiling stains or blistering paint inside the home. Water has already saturated the underlayment and is now soaking into the decking. The longer it sits, the more plywood you’ll be replacing.
• Soft spots or visible sagging when you look across the roof plane. Rotted decking loses its structural integrity. In Orlando’s summer humidity, once wood starts to rot it accelerates fast – mold grows in as little as 48 hours on a wet deck board.
• Granules in the gutter that look like dark sand. As shingles age and shed mineral granules, the underlayment takes on more UV and water exposure than it was designed for. If you’re seeing heavy granule loss, the underlayment below may already be brittle.
• Musty odor in the attic after rain. Trapped moisture in the decking creates a damp, earthy smell. This often appears in Orlando older homes where attic ventilation is already poor, especially during the late summer thunderstorms.
• Visible underlayment tears near the eaves or rake edge. Wind-driven rain can work under the shingle edge and tear the underlayment flap. Left unrepaired, the next storm pushes water directly onto the decking.

Replacement Cost & What’s Included

In Orlando, most CertainTeed underlayment replacements run $350 – $850 per square (100 square feet of roof area). The range is driven by roof pitch – a steep second story adds labor and safety equipment – and whether the old underlayment is mechanically fastened or adhered. Rotted decking runs $2.50 – $4.50 per square foot to cut out and replace with new CDX plywood. For a 2,000-square-foot roof with about 60 square feet of deck rot, a typical Orlando owner should expect to invest $2,700 – $5,000. Every quote from Tilehurst Roofing Orlando includes the CertainTeed underlayment, the decking plywood, all fasteners and drip edge, the labor to tear off the affected area, haul-away, and a written guarantee on the repair. We give you the price before we touch the roof – and we mean it.

DIY or Call Us?

An owner can safely inspect a few things from the ground or from an attic ladder: look for the stains, the soft spots, the granule pileup. What an owner should not do is pull up shingles on a hot Orlando afternoon to peek at the underlayment. That shingle layer is sealed – once you break the seal, you’ve compromised the very layer that was keeping water out. If you’re not experienced walking on a roof, you’re also risking a fall that costs far more than the repair. Deck replacement involves cutting out rotted wood with a circular saw while standing on the roof framing – that’s professional work, no way around it. Greg Holloway has walked thousands of Orlando roofs and finds the same thing time and again: small leaks turn into big deck replacements because someone waited. Call (850) 303-7235 and we’ll come out, walk the roof, and tell you exactly what’s failed and what it costs to fix. No charge for the estimate.

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