Tamko Underlayment & Deck Repair Nationwide

Tamko Underlayment & Deck Repair: The Dallas Owner’s Guide

We stock and install Tamko-compatible underlayment and decking for Dallas homes, and most repairs run between $450 and $1,400 installed depending on how much decking has rotted and which Tamko underlayment your roof needs. We keep TW-40 and TW-60 Tamko underlayment rolls on the truck, plus 7/16″ and 1/2″ CDX plywood for deck repair, so we can typically handle the job in one visit. Most Dallas homeowners discover the problem the same way: a leak shows up on the ceiling after a storm, or a roofer doing a shingle replacement lifts a section and finds the underlayment has torn away or the decking underneath has gone soft from years of trapped moisture in our summer heat.

Call (432) 302-5605

If your Tamko shingles are fine but water is getting through anyway, the underlayment or decking is almost always what failed first. It’s the layer nobody sees until something goes wrong, and in Dallas it takes a beating from hail, wind-driven rain, and attic heat that bakes the underside of the roof well past 130 degrees in August. We’ll walk you through exactly what goes wrong, what it costs to fix, and how we handle the repair from the first phone call to the final nail.

Key Takeaways

• Tamko underlayment and deck repair in Dallas typically runs $450 to $1,400 installed with written pricing before we start.
• We stock Tamko TW-40 and TW-60 underlayment plus CDX plywood decking, so most repairs happen in one trip.
• Every Mercer Roofing repair includes a 365-Day Done Right Promise and a written guarantee before work begins.
• You’ll know who’s coming: we send the technician’s name and photo before arrival, and they badge in with photo ID at the door.

Which Tamko Models This Applies To

Underlayment and decking aren’t tied to a single Tamko shingle line the way a starter strip or ridge cap is. If your roof carries Tamko Heritage, Titan XT, Elite Glass-Seal, or MetalWorks panels, the underlayment beneath them is installed to Tamko’s spec but it’s a field product: TW-40 (a 40-pound-class organic felt underlayment) or TW-60 (a heavier 60-pound-class felt) are the two Tamko-branded underlayments most likely under your shingles in Dallas. Some newer Tamko installs use TW Metal and Tile underlayment, a self-adhering membrane made for metal and tile profiles, and we’ve pulled that off more than a few Dallas roofs where a previous crew used the wrong thing.

The compatibility gotcha we see often: a homeowner has a premium Tamko shingle, but the original installer cheaped out and laid a generic #15 felt under it. That felt rots faster, tears along the deck seams, and shortens the whole roof system’s life. When we open a section, we match the replacement to Tamko’s underlayment recommendations for that shingle class and to Dallas’s wind and hail exposure, not just to whatever was there before. If you’re unsure what’s under your shingles, we’ll document it during the estimate and you’ll see the exact product name and spec in writing before any work starts.

For decking, the decision is simpler: rotted or delaminated sections come out, and new CDX plywood goes in, matched to the existing thickness. On Dallas homes built before the late 1990s we sometimes find 3/8″ decking that’s below current code. In that case we’ll quote the plywood replacement at the right thickness so your Tamko underlayment and shingles have a solid base that won’t flex and crack the sealant strips. We also work with GAF, Owens Corning, and CertainTeed systems, so if you ever need a different brand serviced, the same crew can handle it.

Signs Your Tamko Underlayment & Deck Repair Is Failing

• Water stains on ceilings or walls that show up after wind-driven rain. This often means the underlayment has torn at a seam or pulled away from the decking, letting water run sideways under otherwise intact shingles. It’s not always a shingle problem; we’ve fixed several Dallas homes where the shingles looked fine from the street and the leak was entirely underlayment failure at a valley or penetration.
• Soft or spongy spots when walking the roof. Decking that’s absorbed moisture over a few seasons loses its structural bite, and the nails holding your Tamko shingles start backing out. If a roofer has ever said your roof feels “bouncy,” that’s decking rot, and it only gets worse with each freeze-thaw cycle Dallas gets in January and February.
• Granule loss on Tamko shingles but no visible cracking. When the underlayment traps moisture against the shingle underside, the asphalt layer degrades faster and the granules loosen. It looks like normal aging but it’s actually the underlayment holding water where it shouldn’t.
• Visible underlayment from the eaves or rake edges. If you can see torn, curled, or flapping felt at the roof edge, the weatherproofing at the perimeter is already compromised. Dallas’s spring wind gusts, especially in older Highland Park or East Dallas neighborhoods with mature trees, peel back underlayment at the edges first.
• Attic mustiness or rust on nail points poking through the decking. When the underlayment fails, moisture moves into the decking and condenses on the nail shafts in the attic. Homeowners in Lakewood and Casa View tell us they smell it before they see it, a stale damp smell that lingers after rain.

Replacement Cost & What’s Included

For a Dallas home, replacing Tamko underlayment and repairing decking in a localized area (up to about 100 square feet) typically runs $450 to $900 installed. If the rot spreads across multiple deck panels or the underlayment needs full replacement across a roof plane, expect $900 to $1,400 installed. The range depends on three things: how many decking sheets need to come out, whether your roof pitch requires added safety equipment, and which Tamko underlayment we’re matching to your system. TW-40 is the lighter, more economical felt; TW-60 carries a higher material cost but gives you a denser barrier that holds up better in hail-prone areas like Arlington and Grand Prairie.

Every quote from Mercer Roofing is a written, line-item price you’ll have before any work starts. It includes all materials, labor, haul-off of the bad decking, new fasteners, and the underlayment replacement laid to Tamko’s overlap and fastening spec. The price on the estimate is the price on the invoice; we don’t change orders mid-job. After the work is done, you’ll have a written guarantee covering the repair for a full 365 days. If anything fails within that year, we come back on a free second visit and make it right under our 365-Day Done Right Promise.

DIY or Call Us?

What you can safely check yourself: look at your rafters from the attic on a bright day. If you see daylight poking through gaps in the decking, water staining on the wood, or rust rings around nail points, that’s worth a professional look. You can also check your roof edges from the ground with binoculars for torn or curled underlayment flapping at the eaves. Those checks cost you nothing and tell us a lot on the phone.

What we don’t recommend: pulling up shingles on a pitched Dallas roof to inspect underlayment yourself. Roof work in the summer heat turns a simple inspection into a slip hazard, and lifting shingles without warming the sealant strip can crack tabs that were fine before. The deeper issue is that underlayment and decking failures hide under materials that have to come off in the right order to keep the repair watertight. Getting the overlap, the nail pattern, and the deck seam placement wrong is how a $200 DIY patch becomes a $1,200 re-repair next spring. If you want it done once and backed in writing, call (432) 302-5605 and we’ll give you an honest read, with a written price before anything gets pulled apart.

FAQs