How to Keep Water Out of Your Custom Home: The Right Way to Build Exterior Walls

We’ve all heard the stories—whether on the news or from a friend—about the costly damage caused by water intrusion. Beyond just the financial burden, it often takes significant time and effort to repair. That’s why it’s so important to treat water management as a serious priority when designing your home. Thankfully, there are many smart construction practices that experienced builders and architects can recommend to help protect your investment from the start.

When people think about waterproofing a home, their minds often go straight to a solid roof structure, long soffits or good gutters. While those are important, equally critical is the protection of your exterior walls. Here are some things we have found over the years of building and waterproofing exterior walls:

A common misconception is that the siding—whether it's Hardie, cedar, or another finish—is the waterproofing layer. But in residential construction, we consider those finishes to have zero waterproofing value. The actual water protection comes from what's underneath. For custom homes, there are two main systems Rivendale Homes Texas uses to create a water-resistant barrier around your home: 1) DuPont Tyvek® Wrap or 2) the ZIP System® sheathing.

Here’s a quick breakdown of both systems to help you understand the options:

Option 1: DuPont™ Tyvek® Wrap

Tyvek is a breathable building wrap that sits behind the siding. It keeps rain and wind out while allowing moisture from inside the wall to escape. This prevents mold, rot, and long-term damage.

It looks like paper, but it’s actually made of high-density polyethylene fibers—lightweight, durable, and engineered for performance.

At Rivendale Homes, we follow these best practices when installing Tyvek:

1. Capped Staples – We fasten the wrap using staples with plastic caps. The cap helps prevent water intrusion at each staple point.
2. Compatible Tapes & Sealants – We only use DuPont tapes and caulking around windows and doors to ensure full compatibility with the wrap.
3. Certified Training – Our team receives hands-on training directly from DuPont reps to ensure every install meets manufacturer standards.

Option 2: ZIP System® Sheathing

The ZIP System is known for its distinctive green and orange panels seen on job sites across Austin. It’s a structural plywood panel with a built-in waterproof coating, combining sheathing and a water-resistant barrier in one step.

Key advantages of the ZIP System:

1. All-in-One – It simplifies the process by combining the structural sheathing and waterproofing layer.
2. Nailing Depth Requirements – Correct nail depth is essential to maintain the integrity of the waterproof barrier.
3. System Compatibility – We use ZIP-approved tapes and caulks and regularly invite the manufacturer’s reps to train our team and inspect installations.

So Which One Is Better?

Both are excellent systems when installed properly. That’s the biggest emphasis: a waterproofing system is only as good as its installation. The real difference often comes down to builder experience and installation quality.

• ZIP System is often preferred by architects and speeds up the process of getting the home protected from the outside elements. This is recommended when doing multi-levels of stucco or brick finishes on the second floor.
• Tyvek Wrap is typically more cost-effective and still offers strong performance when installed correctly. Highly recommended on single story home.

At Rivendale Homes, we’ve successfully used both systems. Our priority is proper installation and long-term performance, no matter which product you choose.

Need Help Deciding?

We’re happy to coordinate with your architect and engineer to determine which system best suits your home. Water is one of the most destructive forces in construction—our goal is to protect your entire home, not just your roof, from water intrusion. Your home isn’t just an investment—it’s a place for your family to relax and enjoy, with confidence that it’s protected from water problems. With Rivendale Homes, you can build with confidence—one exterior wall at a time.