Energy Efficient Custom Homes in Grand Rapids
R-Value Homes is a leader in sustainable home construction in Grand Rapids and throughout West Michigan. We specialize in building custom ICF (Insulated Concrete Forms) homes to deliver maximum efficiency, comfort, and health that stand the test of time. What makes us unique? The science. The precision. The results. Let us fully explain why an ICF home is the right choice for your energy-efficient home in Grand Rapids.

What Makes ICF Efficient?

The short answer is that Insulated Concrete Form walls are an important puzzle piece. Our standard ICF wall has an R-value of 23. You can easily upgrade to r-35 and beyond, but you may not want or need to do that. R-value alone is not the entire picture. Our homes perform well because EVERY piece of the home has been tuned to work as a system to deliver exceptional energy performance. In other words, it isn’t ICF construction alone. ICFs do, however, have a very significant role to play. Let’s briefly explore the factors that form the triangle of energy efficiency. 

Better Insulation

    • While every type of insulation has its purpose, some insulations are better for your home’s walls. Loose fill insulations, while popular, are particularly prone to convective looping. Let’s imagine we have an insulated wall cavity that is perfectly air-sealed (and air leaks only exacerbate the problem). Normal winter weather circumstances of frigid air outside and heated space on the other introduce a convective force: one side heats the air within the insulation while the other side cools it. Air circulates within the insulation from one side to the other, and this convective current only increases in speed as the temperature outside drops. Thus, the colder it gets, the more rapidly your walls lose heat. The thermal performance declines just when you need it the most! Energy-efficient homes in Grand Rapids rarely feature loose-fill insulations, especially not in the walls.
    • Solid insulations such as Expanded PolyStyrene (EPS), do not have this problem,  as they prohibit air movement. But not all solid insulations are equal, either. There are some whose performance degrades quite dramatically as the mercury drops. So, solid insulation is better, except when it's not—got that? If you’re taking notes on energy-efficient building materials, specify EPS insulation, and all will be well.
Continuous Insulation

    • Continuous insulation refers to how the concrete core of the wall is sandwiched between uninterrupted layers of EPS insulation. Understanding why uninterrupted insulation is far superior to conventionally framing and insulating a wall isn't difficult. Just try downhill skiing in West Michigan with an exposed midriff!
    • Much of a wall cannot be insulated when stick framing; in most cases, the framing displaces over 20% of the insulation. This is making Swiss cheese out of our insulation “coat”! Thus, the actual performance of a stick-framed wall dismal when compared to the rated performance (r-value) of the insulation. This may be small potatoes in Honolulu, but modern green homes in Grand Rapids must pay attention to such matters. 
Thermal Mass

    • Think of the concrete mass in the center of that insulation as a giant battery that takes a long time to charge and discharge. The difference is that this battery stores heat, not electricity. This long time period evens out the highs and lows of the day or week. The thermal mass of an insulated concrete home means you will never be too cold one night and too hot the next day.
Comfort is Consistency

Perhaps the first thing you think of is a plush leather couch, or maybe it is a sunny beach; it could even be a crackling fire. Whatever comes to your mind probably doesn’t include shivering or sweating. Safe to say, then, that temperature matters. While those of us who are married certainly know that our spouse’s ideal temperature can be different from our own; science has taught us a lot about optimal thermal comfort in our custom homes. We’re here to break it down for you, and maybe even end the arguments over thermostat settings!


 

Understanding Heat Transfer

    • Have you ever been outside in 40 or 50-degree air, yet comfortably warm when the sun is shining brightly on you? Or have you ever felt chilly, even when the air temperature was 70 degrees? If so, you have experienced heat transfer through radiation; it is not related to air temperature. In the one case you are absorbing heat from the sun,  in the other radiating heat to cool surfaces. Radiation is the primary way our bodies experience temperature in our homes.
    • “Heat rises.” We’ve all been told that for years, and most of us have probably repeated it at one point or the other. But did you know that it is wrong? The second law of thermodynamics states that heat moves from hot to less hot. True enough, warmer air rises while cooler air sinks, but this isn’t the whole story.
    • In winter, the coldest thing in the house is typically the windows, with the walls a close second. Even with an Energy Star-rated window, it can perform as low as R-3.1! That is hardly impressive. That feeling of being cold, even when the air temp is 70, is heat moving OUT of our bodies and radiating to a colder surface.

Mean Radiant Temperature (MRT)

    • The temperature that we actually feel in the home is the mean (average) radiant temperature—the average of all the surface temperatures our body experiences at any given moment. This is why a room with many large windows can feel cooler than one without windows when the air temperature is the same. While the air temperature can affect and be affected by the MRT, we don’t feel the air temperature in our home, we feel the MRT.
    • Ideally, we want the surface temperatures in our home to all be very similar to each other and the MRT to be very close to the HVAC setpoint—the temperature at which we set our thermostats. If your home’s construction allows windows, walls, and basement floor to have surface temperatures significantly cooler than the ideal air temperature, we will be uncomfortable next to them. We will want to sit in front of the fireplace or move away from the windows toward the inner part of the room.

    • We have found that keeping surface temperatures within a couple degrees of each other promotes the greatest level of thermal comfort, whether you prefer the thermostat at 65, 80, or anywhere in between!

Air Movement

As we all intuitively know, moving air impacts our comfort; and inside a conditioned home, it is always an aggravating feeling. Air movement can come from many sources, including:

 

    • HVAC system moves intermittent high volumes of air and leaking walls, windows, and floors that allow airflow when the wind kicks up

    • Convection causes drafts, even when the HVAC system is not running, and even if a house was perfectly airtight (it's not). Here’s how it works: warm air next to a cool surface, such as a window or wall, cools off and sinks, causing warm air from the home's interior to move in and take its place. This air then cools off and sinks, and the process repeats. The greater the temperature difference between the interior and exterior of the home, the greater the convection, the more uncomfortable the occupants

    • While these are only the basics of thermal comfort, most builders and too many HVAC contractors do not understand them. Yet, the many assumptions and decisions they make when building a home can have an adverse effect on your personal comfort. The American Society of Heating, Refrigerating, and Air Conditioning Engineers (ASHRAE) has an entire publication devoted to this. Has your HVAC contractor even heard of it?

Air-Tight Health

An airtight home is the healthiest home. Building your new home airtight is key to building the most comfortable home you have ever experienced. The less air leakage through the home, the more durable the home. And an airtight home is the foundation of an efficient home.

Air Pollution Comes From Inside and Out
 

Step 1 

    • Seal up the home to prevent outdoor pollutants such as dust, pollen, and odors from entering. We’ve discussed air sealing for energy efficiency. But an air-tight home also keeps pollutants out.
ICF Custom Home Builder Michigan
Custom Home Building Grand Rapids Open Front Room-1-1
Step 2

    • Bring in the correct amount of fresh, clean air with the proper humidity. While at first blush it appears an airtight home would trap any pollutants inside, we also ventilate properly. We bring in a controlled amount of fresh, filtered air while exhausting the stale, polluted air.

    • We accomplish this using either an Energy Recovery Ventilator (ERV), or a Heat Recovery Ventilator (HRV). We don’t rely on “natural” air leakage to provide a sufficient amount of healthy air for building occupants. That is simply wishful thinking. On a calm day, modern homes do not change adequate volumes of air to provide occupant health. On a blustery day, they may leak too much air. And “natural” air leakage is unfiltered, unconditioned, and likely contains too much or too little humidity.
Step 3 

    • Regulate humidity. The Centers for Disease Control and Prevention (CDC) recommends keeping interior humidity below 50% to eliminate the possibility of mold growth.  Most mold species require 70% or higher relative humidity levels to grow.
    • Conversely, when the humidity levels are too low, viruses flourish. Commenting on recent research, WebMD reports: “By raising indoor relative humidity levels to 43 percent or above, investigators reported that they were able to quickly render 86 percent of airborne virus particles powerless.”  As most homes experience dry air in the winter months, is it any wonder that the winter is also when cold and flu symptoms peak?
    • The bottom line: Humidity can be controlled much more readily when uncontrolled air is not freely moving in and out of the home. In fact, you will find that the air in your new ICF home remains comfortable all year around: not so dry in the winter that you have itchy skin and not so moist in the summer that you feel clammy.
Humidity Levels In Your Michigan Home
Filter the Air in Your Michigan Home
Step 4 

    • Filter the air. Americans care about their health. Many spend thousands per year on supplements, health clubs, etc. Given the amount of time we spend inside, our homes can significantly impact our health. Our comfortable, efficient homes markedly improve levels of mold, viruses, bacteria, Volatile Organic Compounds (VOCs), temperature swings, dust, pollen, CO2 level, and Oxygen level when compared to traditional new homes.
    • All of our homes are filtered to at least MERV 13, which can filter out most mold spores, bacteria, and smoke. Optional filtration up to MERV 16 is available. That is as pure as a hospital surgical room!
    • A recent study confirmed what many have known for a while: People working in well-ventilated buildings are more productive and score higher on tests.

    • The health benefits of an airtight, well-ventilated home are significant and undisputed. Whether certified as a Healthy House by the American Lung Association or simply well-planned, building with R-Value Homes will offer the highest indoor air quality, efficiency, and comfort. It could change your life!
R-Value Homes Creates Ultimate Efficiency and Comfort for Custom new homes in West Michigan