IKO Underlayment & Deck Repair in Los Angeles, CA

IKO Underlayment & Deck Repair: The Los Angeles Owner’s Guide

IKO underlayment and deck repair in Los Angeles typically runs $1,800-$4,200 installed, depending on how much decking needs replacement and whether we’re working with IKO’s ArmourGard or StormShield synthetic lines. We stock both on every truck, and most jobs finish in a single day. Homeowners usually spot trouble after a Santa Ana wind event or the first hard rain in November - water stains on the ceiling, shingles that look fine from the street but are riding on compromised backing, or that soft give when you walk the roof that means plywood has turned to mush underneath.

Call (844) 563-1816

Which IKO Models This Applies To

IKO’s underlayment systems pair with their full shingle catalog, but the specs change by line. ArmourGard UDL is the workhorse we see on most Los Angeles installs from the last decade - a synthetic mat rated to six months UV exposure, which matters here because permits can drag and that sun doesn’t wait. StormShield is the premium ice-and-water barrier, required by L.A. County code in certain hillside zones and smart anywhere you get wind-driven rain against valleys or eaves.

To identify what you’ve got, check the printed run along the underlayment edge if any is exposed at the rake, or look for the IKO lot sticker on shingle bundles left in the garage. The critical compatibility gotcha: IKO’s synthetic underlayment runs 48 inches wide, where some competitors cut corners at 36. If your roofer last time substituted generic felt, the fastening pattern won’t match IKO’s spec, and that’s often where the blow-off starts. We carry OEM IKO underlayment and decking - no substitutions - but we’ll tell you straight if your existing underlayment is sound enough to leave in place and save you the tear-off.

Ridgeline Roofing Co. is an independent service provider, not affiliated with IKO. We’re authorized to install their products properly, which is what your warranty actually requires.

Signs Your IKO Underlayment & Deck Repair Is Failing

• Water spots that appear after rain but shrink in dry weeks. This pattern usually means the underlayment has torn or wrinkled, letting water through to the deck, but the deck hasn’t fully rotted through yet. Caught here, you may only need underlayment replacement and a few sheets of plywood.
• Shingles lifting or creasing in straight lines. IKO underlayment that’s buckled from poor installation or heat creates a hump the shingles can’t lie flat on. The shingles aren’t defective - they’re riding on a roller coaster underneath.
• Sagging between rafters when viewed from the attic. Plywood decking loses structural integrity around the 15-20 year mark in Los Angeles, faster if the attic ventilation was done wrong and summer heat builds to 140 degrees. IKO’s warranty covers their underlayment, but not the deck it was nailed to.
• Granules collecting in gutters after Santa Ana winds. Heavy granule loss often traces to shingle flex caused by spongy decking underneath. The shingle takes the blame, but the real problem is the deck giving way.
• Daylight visible through the roof boards from inside. This is past the point of patching. Once decking has delaminated this far, moisture has compromised the underlayment fasteners and the whole assembly needs to come off.

Replacement Cost & What’s Included

What drives the range: how much decking is actually bad (we probe with an awl and photograph everything), whether we’re working around solar panels that need a hold-down crew, and access - a two-story in the Hollywood Hills with no driveway costs more than a single-story in the Valley with a clean roofline. Our estimate is the number on the invoice. The 90-Day Done Right Promise covers the workmanship, and we register your IKO material warranty so there’s no paperwork runaround if you ever need it.

DIY or Call Us?

Here’s what you can safely check from the ground or attic: look for the signs above, note where they appear, and take photos with something for scale. What you should not do is walk the roof yourself. Los Angeles sees more than its share of falls from homeowners who trusted 20-year-old decking to hold their weight. The plywood may feel solid at the edge and give way two feet in - a roof doesn’t lie, it just waits until the rain to tell you the truth.

Removing shingles to reach underlayment requires proper tear-off technique, and installing new underlayment means sealing the laps to IKO’s spec so wind can’t get underneath. Miss that, and you’re doing it twice. If you’re handy and want to handle the interior drywall repair yourself after we’re done, that’s a square deal. The roof work belongs to someone who does it every day. Call (844) 563-1816 and we’ll walk you through what we found, no charge for the look.

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