If you're planning a stone veneer or stucco project, using delta dry and lath might be the best decision you make for the long-term health of your home. It's one of those products that doesn't look like much—just a roll of dimpled plastic with some mesh on top—but it solves a problem that has been a literal nightmare for homeowners and builders for decades. We're talking about moisture. Specifically, the kind of moisture that gets trapped behind your siding and slowly rots your sheathing until you're looking at a five-figure repair bill.
For a long time, the standard way to do things was to slap some building paper or housewrap on the wall, nail up some metal lath, and start throwing mud. It worked "well enough" for a while, but as we started building tighter, more energy-efficient homes, that old-school method started to fail. Without airflow, any water that got behind the stone just sat there. That's where a 2-in-1 system like this steps in to change the game.
Why the Old Ways Aren't Cutting It Anymore
Let's be honest: traditional metal lath is a pain. If you've ever spent a day handling it, you know exactly what I mean. Your hands get sliced up, it's heavy, and if you don't get your overlaps perfectly right, you're asking for trouble. But the real issue isn't just the installation; it's what happens ten years down the line. Metal can rust. When metal lath sits in a damp environment behind stucco, it eventually starts to degrade.
More importantly, traditional systems often lack a "capillary break." This is just a fancy way of saying there's no gap for water to drop down or for air to move through. When the sun hits a wet stone wall (something pros call "solar vapor drive"), it actually pushes that moisture inward toward your wooden studs. If there's no space for that vapor to escape, it's going to find a way into your plywood or OSB. By the time you see a brown stain on your indoor drywall, the damage is already done.
What Makes This System Different?
The beauty of the delta dry and lath setup is that it combines two crucial steps into one product. You've got the high-density polyethylene (HDPE) dimpled membrane which acts as your drainage plane and vapor barrier. Then, fused right onto the top of those dimples, is a glass-fiber lath.
Because of those dimples, the siding is held away from the house by about 10 millimeters. This creates a dedicated airspace. If water gets behind the stone—and let's be real, water always finds a way in—it just runs down the back of the dimples and exits through the weep screed at the bottom. Meanwhile, air can circulate behind the cladding, drying out any residual dampness. It's like giving your house a set of lungs so it can breathe behind its "skin."
The Perks of Ditching Metal
One of the first things you'll notice when working with this stuff is how much easier it is on your body. Fiberglass lath doesn't have those razor-sharp edges that metal does. You can cut it with a simple utility knife or a pair of snips without feeling like you're in a sword fight.
Another huge plus is that it doesn't corrode. Since it's made of alkaline-resistant glass fibers and plastic, it's completely indifferent to moisture. You could leave it in a bucket of water for a year and it wouldn't change. That kind of durability is exactly what you want when you're burying a material behind layers of mortar and stone that you never want to touch again.
Installation Isn't as Scary as it Looks
If you're a DIYer or a contractor moving away from traditional methods, the learning curve here is actually pretty shallow. You start with your base flashing and weep screed, then you start rolling out the membrane.
One thing people often ask is about the "shingle fashion" overlap. With this system, you just overlap the flat edges of the rolls to ensure water stays on the outside. You fasten it using wide-head nails or staples, usually every 6 to 12 inches depending on your local codes. The cool part is that because the lath is already attached, you don't have to worry about the mesh sagging or moving around while you're trying to get your scratch coat on.
Speaking of the scratch coat, the fiberglass mesh is designed to really "grab" the mortar. You get a solid mechanical bond that feels every bit as sturdy as the old metal stuff, but without the risk of the lath being pushed too close to the wall. The dimples keep everything at a consistent depth, so your mortar layer stays uniform.
Managing the Corners and Seams
Corners are usually where people get a little nervous, but it's pretty straightforward. You just wrap the material around the corner, ensuring it's tight and secure. For the seams where two rolls meet vertically, most people use a bit of construction tape or just ensure the overlap is sufficient. The goal is simple: don't give the water a "shelf" to sit on. You want every path to lead downward and out.
It's also worth mentioning windows and doors. You still need to do your due diligence with flashing tape (like a high-quality butyl tape) around your openings. The delta dry and lath sits over your flashing, acting as the final defense. It's a belt-and-suspenders approach that really pays off during a heavy storm.
Is the Extra Cost Worth It?
I won't lie to you—this system costs more upfront than a few rolls of tar paper and some cheap metal mesh. If you're looking at a spreadsheet and only focusing on the material cost for today, you might be tempted to go the cheap route.
But you have to look at the "hidden" savings. First, you're saving labor. Combining the rainscreen and the lath into one step means you're walking around the house once instead of twice. That's a massive time-saver. Second, you're buying insurance. The cost of replacing a rotted wall in ten years is astronomical compared to the few hundred extra dollars you might spend on a high-performance drainage mat now.
In the building world, we often talk about "resilience." A resilient house is one that can get wet and dry out without failing. This system is basically the definition of building for resilience.
Real-World Performance
I've talked to guys who have gone back to jobsites where this was installed years prior, sometimes to do an addition or a renovation. When they peel back a section of the stone, the sheathing underneath looks brand new. No rot, no mold, no "funky" smells. That's the dream.
Especially in climates that get a lot of rain or have high humidity, the airflow provided by the dimples is a lifesaver. Even if the installer makes a tiny mistake with the caulking around a window, the drainage gap provides a "path of least resistance" for that water to escape before it can soak into the wood.
Wrapping it Up
Choosing delta dry and lath is really about peace of mind. It's about knowing that even if the weather gets crazy or the stone veneer develops a tiny crack over time, your house is protected. It simplifies the messy, complicated process of moisture management into a single, manageable product.
If you're tired of fighting with rusty metal lath or worrying about what's happening behind your stucco, it's definitely worth looking into. It's a modern solution to a very old problem, and honestly, once you see how much sense it makes, it's hard to go back to the old way of doing things. Whether you're a pro or just a homeowner trying to do right by your house, this is one of those upgrades that actually earns its keep.