Building a Better Thermal Envelope

Green construction experts at Hibbs Homes share how they're making Proud Green Home St. Louis even more energy efficient.

Just like the computer you are reading this on, the technology that keeps your home humming is always evolving. With the introduction of design innovations and due to basic wear and tear, a home's HVAC system is a system component that most homeowners will upgrade after about 15 years or more, depending on the system you've invested in. This being the case, investing in the design and details of the bones of your home - the studs, joists, and other behind the walls systems that you don't see that create your home's structure - makes a lot of financial sense.

One high-performance building principle that guides Hibbs Homes, and that we have relied on for the design of Proud Green Home St. Louis, is controlling building and maintenance costs and protecting future equity position to ensure a home's current and future sustainability. To that end, we dedicated a lot of time to the sheathing and framing of Proud Green Home St. Louis to make sure that the home's thermal envelope will consistently out-perform that of a conventional home for decades, no matter what HVAC system is installed.

Thermal Envelope Components

The roof and wall sheathing used in the Proud Green Home St Louis is Huber's 7/16" ZIP System, and we designed and framed the home using advanced framing techniques. We will get into the finer details of what that means in a moment, but together these building choices create a durable, efficient building envelope than can be found in a home built using traditional framing and sheathing techniques.

Advanced Framing Techniques

To further optimize Proud Green Home St. Louis's energy performance, and to reduce waste and lumber costs, we used advanced framing techniques, also known as Optimal Value Engineering, during design and construction. Advanced framing eliminates framing redundancies, creating more room for insulation without compromising the structural and architectural integrity of the home, and still surpasses building codes. We also used raised heel trusses, known as energy trusses, in the home's construction. These trusses are oversized to increase the height on exterior walls allowing more room for insulation on the outside of the home.

ZIP System

If you ever played with a modeling kit as a kid, the ZIP System will make a lot of sense to you. Like a model kit, the home's exterior is composed of a series of panels that were manufactured off-site using precise measurements from the building plans. Each panel is made of a layer of highly efficient insulating foam sandwiched between two layers of engineered oriented strand board. They are shipped to the construction site where they fastened to the home's frame and taped at the seams using a permanent adhering tape made by the manufacturer. These large continuous panels reduce the number of seams in the thermal envelope to create a better barrier against air and moisture exchange, also know as thermal bridging.

The thermal envelope is one of the most important systems that work in conjunction with other home components to create a home that operates as a holistic high-performance system. We will continue to share videos, photos, and blog posts discussing other components of Proud Green Home St Louis as construction continues both here on our blog and on

Building Materials

In addition to building your home with a tighter thermal envelope, we work to use recycled and renewable materials whenever possible. From repurposed and reclaimed wood for shelving and decor to plant-based polyurethane rigid foam in our insulation, we take measures to minimize our environmental impact at every step of the way.

You can also learn more about this project and other high-performance showcase homes we've built in St. Louis by calling us at 314-581-8205 or visiting our new homes portfolio.