Free written scope consultation - allowances, timeline, and change-order rules on paper before a single trade is scheduled
Tamko Home Additions & ADU: The Dallas Owner’s Guide
If you’re planning a home addition or ADU in Dallas and want Tamko roofing and waterproofing products specified into the build, we can help. A full addition or ADU project in Dallas typically runs $45,000 – $130,000 for the addition itself, and $90,000 – $220,000 for a detached ADU, depending on square footage, foundation work, and finish level. Most owners reach out to us after realizing their existing structure’s envelope, the roof deck, flashing, and underlayment, wasn’t done right the first time and now the new space needs to tie into something that holds.
The most common way this conversation starts: a homeowner has a patio cover, garage, or bonus room that’s leaking at the transition where old roof meets new, or they’re about to pull permits on an ADU and want the roof system specified correctly before the first truss goes up. The fix is rarely one part. It’s a system decision, and getting the Tamko-compatible underlayment, flashing, and shingle spec right on the front end saves a re-roof on the back end.
Key Takeaways
- Tamko products are a specified material choice on additions and ADUs, not a standalone “part” like a spring or valve
- Dallas additions run $45,000 – $130,000; ADUs run $90,000 – $220,000
- The failure point is almost always the transition: old envelope meeting new envelope
- Bradford Remodeling Co Dallas writes a fixed price before work starts, and the 365-Day Done Right Promise covers the completed project in writing for a full year
Which Tamko Models This Applies To
Tamko makes a range of roofing and waterproofing products that matter on additions and ADUs: Heritage and Elite shingle lines, Titan XT underlayment, TW-60 self-adhered membrane, and their metal flashing and ridge accessories. On a Dallas addition, the specific Tamko product you’re dealing with depends on your roof pitch, the age of the existing roof, and what your local code requires for ice and water shield on the eaves and valleys.
One compatibility gotcha we see in Dallas: if your existing home was roofed 12 to 15 years ago with a discontinued or reformulated shingle line, you can’t always match the exact Tamko color and profile on the new addition. That’s not a defect. It’s a fade and production-run reality. We’ll tell you before we write the scope whether we can match it close, or whether the cleanest solution is to re-roof the main structure and the addition in one pass so the whole envelope matches, both in appearance and in warranty coverage.
Styles & brands we work with
Signs Your Tamko Home Additions & ADU Is Failing
- Leaking at the transition seam. The point where the addition’s roof ties into the original house is the weak link. Poor step flashing or missing peel-and-stick membrane at that junction lets water run inside the wall cavity. In a Dallas downpour, that leak can show up 10 feet from the actual opening.
- Shingle granule loss on the new roof within the first three years. Some granule loss is normal, but heavy, localized loss usually means the shingles were installed in cold weather or nailed outside the strike zone. That shortens the roof’s life and voids the manufacturer’s wind warranty.
- Rust or corrosion at flashing points. If the crew used plain galvanized flashing against a treated lumber roof deck on the addition, the chemical reaction eats through in three to five years. Tamko’s accessory line includes corrosion-resistant options, but only if they’re specified.
- Sagging or soft spots at the addition’s roof edge. This is almost always a substrate problem: OSB that got wet during framing and was closed in before it dried. The shingles can’t fix that. The decking has to come off and go back on dry.
- Water staining on the ceiling of the new space after a hard wind-driven rain. Dallas gets those. If water is getting in during wind events but not calm rain, the issue is usually at the ridge or the sidewall flashing on the addition, not the field of shingles.
See the difference
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After
Before
After
Before
AfterReplacement Cost & What’s Included
The numbers for a Dallas addition involving Tamko-specified roofing and waterproofing break down like this:
| Scope | Typical Dallas Price Range |
|---|---|
| Full home addition (wet space, foundation, roof tie-in) | $45,000 – $130,000 |
| Detached ADU (full build) | $90,000 – $220,000 |
| Garage conversion | $30,000 – $80,000 |
| Roof replacement tied into an addition | $8,000 – $20,000 |
What drives the range on additions: foundation conditions in your Dallas neighborhood, whether the existing home’s framing is still square or if the 1950s-era plaster is going to fight us at the tie-in, and what your city requires for setbacks and drainage on an ADU. Every scope we write has the Tamko products named by product line, the substrate and flashing method called out, and a line-item price. Nothing moves at the door. The 365-Day Done Right Promise covers the completed project for a full year, and if the roof tie-in fails inside that window, we come back and correct it at no charge.
Call (903) 326-8963 for a written estimate on your addition or ADU. The number you get is the number you’ll pay.
DIY or Call Us?
If you’re not doing the structural work yourself, then the roofing and waterproofing decision is a specification question, not a DIY question. You can safely verify a few things without getting on a ladder: check the soffit and fascia on your existing home where the addition will tie in, make sure the plans call out roof pitch and drainage, and confirm the jurisdiction is Dallas proper so the permit path is clear. Those are the things a homeowner can do on paper.
What you shouldn’t do is let a crew hand you a verbal “we’ll match the roof” promise. Roofing an addition involves step flashing, ice and water shield at the eaves in Dallas’s code environment, and a Tamko-rated underlayment under the shingles. If that assembly is wrong, you won’t know until the first north Texas thunderstorm. Our technicians are on site, the scope is written, and the warranty is signed. Straight number, real scope, no surprises on delivery day. Call (903) 326-8963.
FAQs
A properly installed Tamko shingle system on a new addition should hold for 25 to 30 years in Dallas weather, assuming the flashing details and underlayment are done to manufacturer spec. The first failure on a bad install usually shows up at the transition seam within three to five years, well before the Tamko material itself ever fails. Call (903) 326-8963 if you want us to look at an existing tie-in that’s already leaking.
If the failure is isolated, a repair at the flashing or a single valley is often enough. But when the underlayment or decking is compromised along the tie-in, a repair becomes a band-aid on a structural problem. We’ll tell you which one you have after a site walk, and the written estimate will show exactly what’s repairable and what isn’t. Estimates are free, call (903) 326-8963.
For a typical Dallas addition, the roof and waterproofing work is done in two to four days once the framing is set and the inspection on the decking passes. The full addition, including rough-in, finishes, and closeout, runs six to fourteen weeks depending on scope. Your written schedule comes with the written price, so you’ll know the sequence before we start.
We can source Tamko Heritage, Elite, Titan XT, and related flashing from our Dallas suppliers on a project basis, and we coordinate delivery so material isn’t sitting on your lot getting rained on before the decking is ready. We also work with KraftMaid, Cambria, and Silestone on the interior finish side, so the whole addition is specified from one documented roster of brands.
No. The price we write for your Dallas addition or ADU is the price you pay, unless you change the scope. If we open a wall and find something that has to be addressed, we stop, show you what we found, and put the change order in writing before we touch it. That’s the Garrison Standard, and it’s been the rule here since 2004. Call (903) 326-8963 to schedule a free estimate and get your number in writing.
Written by Curtis Lane, Owner, Bradford Remodeling Co Dallas at Bradford Remodeling Co Dallas, serving Dallas and nearby areas.
