What Makes Us Different?

Any building is only as good as the construction methods used to create it. It is on this purpose that EverGreen Construction came into fruition. Witnessing a lack of efficient and environmentally friendly building techniques in our area, we researched many building systems used throughout the world to create a better structure. At first, we narrowed the field down to several different methods until we could further ground truth the various systems and see how they faired in real life scenarios. Then we went further, visiting the facilities that manufacture the products that go into creating the structure, be it a home or business, to get a first hand look at the quality of work prior to the product reaching the construction site. While most builders don’t see a need to visit the mill that create’s the dimensional lumber that is used to build most homes, we felt that getting to know the facilities that manufacture our Structural Insulated Panels would give us the necessary knowledge on the process behind the scenes and thus create a better relationship directly with our suppliers. It was also a better way to locate a facility that pays as much to detail on the product as we do to our projects.


It all starts with the foundation, and so do our methods of producing an efficient building. If you don’t start here, what is the point in spending the money to seal the envelope of the home in the upper areas since you will always have a weak spot in the efficiency of the home in the basement. We have built slab homes (homes without basements), homes built on a traditional foundation (although we highly recommend against it), homes using ICFs (Insulated Concrete Forms), and lastly our recommended method, the Thermomass Insulation System. This is a system that remarkably mimics the attributes of a Structural Insulated Panel (SIP) in that it is insulation sandwiched between two structural sheets, the “sheets” in this case being two slabs of concrete.



thermomass_poured As you can see from the diagrams above, the DOW Styrofoam (Extruded Polystyrene) is sandwiched in-between two slabs of concrete. One of the huge benefits of this design is that any concrete company can pour with this method and it will fit into their existing forms. Another benefit is that the insulation is completely encased in concrete, leaving nothing to be exposed and therefore secures it from any damage or breakdown. What makes this system unique aside from its design, is the method by which it fits into the concrete forms. If you look again at the diagrams, there are a series of pins that not only hold the foam in the correct location within the concrete form, but also have a very high tensile strength and quite literally hold the cured concrete slabs together as well. The thickness of the foam used can be varied to increase or decrease the overall R-value of the wall, and the placement of the foam itself within the wall can be varied by ordering the necessary pins to hold the sheet in the location desired.

You may also notice something from the diagram above, the system calls for a continued thermal break from the exposed side of the system as well as for the floor, creating a completely isolated system with minimal thermal bridging. The last effect from this system is the Thermal Mass properties that are gained by having an insulated slab of concrete within the conditioned space of the home. Gone are the days with damp basements since the dew point is now located in the outside slab of concrete, and now we have a “storage” slab of concrete that can help even out the temperature in the basement of a home. Want one more nice benefit from using this system? It was invented, engineered and produced right here in Iowa.




Structural Insulated Panels

To create a truly energy efficient building you must first do one thing, seal the building. The movement of air from inside to out, or vice versa, is the easiest way to loose energy from within the home. You will always hear the older builders say that they want their building to breath, but lets face it, it is better and a lot more efficient to control that breathing through an air-to-air exchanger than through the walls of the house where it is not controlled at all. Moisture problems and eventually mold are introduced in that way, and indoor air pollution is one of the leading causes of health problems in the homes built today. If you were asked to either breath through your mouth, allowing you to control it, or berating through your skin, which would you choose? One of the concepts designed with SIPs is this process of sealing the home air tight and controlling it mechanically with an air exchanger. This ensures that fresh air is constantly being introduced into the home at a desired rate all while handling it and having the moisture altered to maintain a healthy humidity in the structure. SIP_wall
SIP_walls_roof From the diagrams above you can see how the SIPs and Thermomass systems are similar, but also different. Insulation is sandwiched between two sheets of OSB creating a very rigid and strong structure. Where two panels are joined, a smaller panel or spline is used to create a continuous insulated system with minimal areas of thermal bridging. The system was build on the idea of energy efficiency and strength, and exceeds energy efficiency building codes without much effort. With the SIP system, we can create a sealed, very efficient envelope that also has other benefits. For one, depending on your preferences, we can create a a relatively inexpensive loft space, a sealed “attic” system that is part of the home or vaulted ceilings that do not reduce the energy efficiency of the building. The SIP panels are also a perfect choice to use on a structural Timber Framed home. Once you seal the exterior of the structure, your possibilities for what you can do on the interior truly open up.

So, in the end, where does this put us? We know from third party testing that we build some of the most energy efficient buildings around. We specialize in perfecting the techniques on how our buildings are assembled, sealed, and eventually finished. While speed is always a consideration on any job site, we put quality first. No short cuts, if something needs to be changed, it will be. In the end, the home or business that we are creating for our client will be used for generations, and we plan on creating a building that will exceed it’s expected lifespan. These building methods are what make our buildings “EverGreen” buildings.


SIP_Loft_Vault Timber_Frame