Free written scope consultation - allowances, timeline, and change-order rules on paper before a single trade is scheduled
Tamko Bathroom Remodeling: The Sherman Oaks Owner’s Guide
Tamko bathroom remodeling in Sherman Oaks typically runs $9,000-$28,000 for a full replacement, with smaller refreshes starting around $5,000. We stock Tamko-compatible waterproofing membranes, underlayment, and finish materials, and we can usually get specialty items from our distributor in the San Fernando Valley within a day. Most Sherman Oaks homeowners discover their Tamko system is failing when they spot water staining on drywall below a second-story bath, or when tile starts sounding hollow after a winter rain cycle that pushed moisture through a compromised vapor barrier.
Which Tamko Models This Applies To
Tamko doesn’t sell a single branded “bathroom system” the way they sell roofing shingles. What we handle are the components Tamko manufactures that end up in bathroom assemblies: TW Metal waterproof underlayment, Heritage Series underlayment used as secondary moisture barriers, and the TAMKO Building Products waterproofing membranes specified by some regional builders in the 2015-2022 window. The compatibility gotcha is that TW Metal comes in 36-inch and 48-inch rolls, and the 48-inch was discontinued in 2021. If your original installer used the wider roll, the replacement must be seamed more frequently, which changes your labor line item.
To identify what you have, look for the Tamko lot stamp on any exposed underlayment edge in the vanity cavity or behind an access panel. The stamp includes a plant code: “W” for White City, Oregon, or “P” for Phillipsburg, Kansas. For Sherman Oaks homes built during the 2017-2019 rush, we see the “W” code most often, as West Coast distributors were pulling from Oregon then. OEM Tamko underlayment runs about 15% more than quality aftermarket equivalents like Grace Ice & Water Shield or Polyguard, but the OEM matches the original permeability rating exactly. We quote both and let the homeowner decide.
Rowan Construction Group Sherman Oaks is an independent service provider with no affiliation to Tamko Building Products, LLC.
Signs Your Tamko Bathroom Remodeling Is Failing

- Soft drywall around the tub or shower surround. This means moisture has breached the Tamko membrane or the seam tape has delaminated. In Sherman Oaks, we see this most often in homes where the original installer used staples instead of cap nails on the underlayment, creating puncture points that wick water over six to eight years.
- Grout cracking in a straight line along the shower curb. The waterproofing pan beneath has likely shifted or the Tamko membrane was cut too short at the curb transition. The substrate is moving because water has degraded the mortar bed.
- Musty odor that returns after cleaning. This points to trapped moisture behind the tile, usually where the Tamko vapor barrier meets the drywall without proper overlap. The Valley’s dry heat can mask this for months, then a humid week makes it unmistakable.
- Tile sounding hollow when tapped. The thinset has lost adhesion because moisture migrated through a failed seam in the waterproofing layer. We find this constantly in Sherman Oaks condos built during the 2016-2018 boom, where speed often won over seam inspection.
- Water stains on the ceiling below the bathroom. The secondary moisture barrier has failed entirely. If the stain spreads after rain, the problem may include roof leakage too; if it spreads after shower use, the Tamko bathroom membrane is the culprit.
Before
AfterReplacement Cost & What’s Included
For a full Tamko bathroom remodel in Sherman Oaks, our installed price ranges from $9,000 to $28,000. A small bathroom refresh runs $5,000-$12,000. Walk-in shower installations using Tamko-compatible waterproofing run $4,500-$12,000, and tub-to-shower conversions land at $3,500-$10,000.
| Component | Price Range |
|---|---|
| Full bathroom remodel (Tamko materials) | $9,000 - $28,000 |
| Small bathroom remodel | $5,000 - $12,000 |
| Walk-in shower installation | $4,500 - $12,000 |
| Tub-to-shower conversion | $3,500 - $10,000 |
| Shower replacement only | $3,000 - $8,500 |
| Bathroom vanity installation | $800 - $3,000 |
What drives the range: square footage, whether we need to replace the subfloor (common in Sherman Oaks hillside homes with original 1960s construction), and whether the homeowner upgrades to a full tile surround or keeps a fiberglass insert. Every quote is a flat written price with a written scope before work starts, under Clause 1 of the Haven Standard. No change proceeds without a signed change order. The 365-Day Done Right Promise covers all workmanship, and the documented photo record from every visit is included, not optional.
DIY or Call Us?

There’s safe homeowner inspection, and then there’s the point where you need a trained crew. You can check the lot stamp on exposed Tamko underlayment, look for obvious seam gaps behind access panels, and run a fan for 48 hours to see if a musty smell returns. What you should not do: cut into a waterproofed shower pan, remove tile to inspect the membrane, or attempt to reseam Tamko membrane with consumer-grade tape. The membrane must be surface-dry and primed to specification, and the overlap pattern matters down to the inch.
We’ve been called to Sherman Oaks jobs where a homeowner’s DIY patch trapped more water than it stopped. Measure twice, write it down, then build it. If you’re seeing any of the five symptoms above, call (213) 221-0788 and we’ll schedule a free estimate with a written price before anyone picks up a tool.
FAQs
Properly installed Tamko membrane should last 20-25 years, but we’ve seen failures at 8-10 years when the original installer missed seam overlaps or used the wrong fasteners. The Valley’s temperature swings, 40°F winter lows to 100°F summer highs, accelerate adhesive fatigue at cut edges. Call (213) 221-0788 for an exact quote on replacement - estimates are free.
Spot repairs work only if the failure is isolated to one seam and the surrounding membrane tests dry and fully adhered. In most Sherman Oaks cases we inspect, moisture has spread beyond the visible damage, and partial repair leaves a ticking problem. We test with a moisture meter before recommending either path. Call (213) 221-0788 for an exact quote - estimates are free.
Most full remodels run 10-14 business days from demolition to final fixture hookup. A shower-only replacement takes 4-6 days. Permits add 3-5 business days for inspection scheduling; we pull all permits and pass inspections as part of the flat price. Call (213) 221-0788 for an exact quote - estimates are free.
We carry standard-width TW Metal underlayment, compatible seam tape, and fasteners on every bathroom crew’s truck. Specialty widths or discontinued 48-inch rolls come from our San Fernando Valley distributor next-day. For most Sherman Oaks jobs, we’re installing within 24 hours of the signed agreement. Call (213) 221-0788 for an exact quote - estimates are free.
We also stock and install parts for KraftMaid, Cambria, and Silestone products.
Written by Grant Rowan, Owner, Rowan Construction Group Sherman Oaks at Rowan Construction Group Sherman Oaks, serving Sherman Oaks and nearby areas.







Before
After
Before
After
Before
After