High-Performance Homes – Water and Energy Efficiency

High-Performance Homes – Water and Energy Efficiency

The Future of American Housing

…is high-performance home building! Homes that are better for us, for our children and grandchildren, and our country. New home buyers want, even expect, a high-performance home. But just as with the word “quality”, the term “high-performance” has been used so many ways in home building that it has become vague and confusing. To provide clarity and a baseline, the National Association of Home Builders (NAHB) published their criteria for constructing a high-performance home around three benefits: comfort, wellness, and efficiency – the subject of this post. 

In looking at a new home, as home buyers, we tend to focus on individual decisions in isolation. A co-worker’s new home was insulated with expanding foam, they love it, and you want your new home built that way, too. Home builders on the other hand understand that a new home is a system, comprised of inter-related decisions. That super-insulated home will call for downsizing the home’s HVAC system and ductwork. Failing to do so would mean wasting money on larger HVAC system components which would cycle on and off quickly, thereby costing you more for utilities, too. And having larger ductwork is like trying to blow through a big, round tube vs. blowing through a straw. It won’t seem like much of the conditioned air is coming out of those oversized ducts.

Fortunately, many of the same decisions which contribute to your comfort and wellness are solutions to achieving an energy-efficient home with lower utility bills. Air sealing measures such as a housewrap, plus close attention to caulking voids and seams, reduce uncomfortable drafts and contribute to the effectiveness of your home’s insulation.

Infographic_Blog4

Building with Structurally Insulated Panel (SIPs), or Insulated Concrete Forms (ICFs) provides superior insulation and air-sealing, drastically reducing energy use. Choosing one of those advanced construction techniques can also affect the design. We’ll use Design Basics’ Cavanaugh plan to illustrate:

8540BL

Plan 8540BL as originally designed with 2x4” exterior walls – 1,699 sq. ft. (without optional 2nd floor expansion.)

8540BL_1

As originally designed, with 9’-high main level walls and 10’-high ceiling in MBR.

8540BL_2

Optional expansion/storage adds 165 sq. ft.

8540FOX

Plan 8540FOX adapted for 11.25” thick ICF exterior walls – 1,877 sq. ft. (without optional 2nd floor expansion.)

8540 ECO_1

The width and depth of the home grew because of the thicker ICF walls, some room sizes changed slightly.

8540 ECO_2

Note: due to their weight, ICFs are used for 2nd-floor walls only when they stack directly over main floor ICFs.

8540SUL

Plan 8540SUL adapted for SIP construction. Note SIP rooflines change slightly. Second-floor loft adds 201 sq. ft. for a total of 1,900.

8540SUL_1

The SIP roof means dramatic ceilings sloping upward from the back of the MBR, Family Room and eating area.

8540SUL_2

Sloping SIP rooflines create a loft overlooking the 1st-floor; BR3’s ceiling slopes up from the front; BR2 has a cathedral ceiling. Also, a play loft can be built above the bathroom and walk-in closet, accessed by a ladder from BR3.

8540SUL_OptPlayLoft

Tight, well-insulated homes can be heated and cooled with less expensive, smaller furnaces and air conditioners. Optimal efficiency and comfort can be achieved when you pair your HVAC equipment with a smart thermostat that “learns” your preferences, continually monitors indoor conditions and operates your system accordingly without your need to adjust it.

ENERGY STAR-rated lighting and appliances complete an energy-efficient home.  LED lighting prices and selection have become so attractive that choosing LED bulbs and fixtures a no-brainer. ENERGY STAR ratings for kitchen and laundry appliances make it easy to take energy consumption into account when selecting your new appliances.  As reported on energystar.gov, “Water heaters account for 12 percent of residential energy consumption.” Several ENERGY STAR-rated water heaters are available, and you can easily recoup the added cost in utility savings.

he question sometimes arises in conjunction with water heaters: which uses more water, tankless, or tank-type water heaters? If you’ve lived in a 2-story home with your water heater in the basement, you know how much water is wasted before hot water reaches your showerhead! But assuming the same location for your water heater – regardless of the type – there’s likely very little if any difference. You have the same amount of cool water to push out of the way before the hot water reaches your shower. This brings up another factor, the length of the water pipe runs. Notice that the Cavanaugh plan’s Owner’s Bathroom, laundry room, and half-bath are in close proximity, and the second-floor bathroom is above the laundry room?

Originally designed on a basement foundation, the Cavanaugh plan’s suggested water heater location is directly beneath the Owner’s Suite walk-in closet, keeping water pipe runs efficiently short.

8540 Basement Highlight

Choosing water-saving dishwashers and clothes washers can cut water consumption in half compared to older models. Further, the US EPA has a program identifying water-saving products for the home, WaterSense. Toilets, faucets, and showerheads bearing the WaterSense label have been certified to meet the EPA’s specifications for water efficiency.

As posted by the EPA, “Nationwide, landscape irrigation is estimated to account for nearly one-third of all residential water use.” And, as much as 50% of that water is wasted, due in large part to inefficient irrigation methods systems! WaterSense labeled products also include both weather-based and/or soil moisture-based sprinkler system controllers which can keep you from overwatering. Finally, selecting grass types and landscape plantings that need less water will further reduce the amount of water used.

Our previous post “It’s Raining In The Basement!” chronicled the woes of a catastrophic water leak in a brand-new home. Following remediation, the new home owners purchased a whole-house water leak detection system. Small wireless remote sensors were placed where leaks if any, would likely occur. Then, should a leak happen, the home’s water supply would automatically be shut off, stopping the leak.

As a nation, we can build better homes, and following the NAHB’s high-performance home guidelines is a fast track to “better”!

For more resources on thoughtful design and products:

High-Performance Homes – Wellness Part 2

High-Performance Homes – Wellness Part 2

“It’s Raining In The Basement!”

True story. Eight days after moving into their newly-built home, while Mom and Dad were away, one of their children was interrupted and left the water running in the laundry room sink. A few minutes later another one of their kids who was playing video games starts yelling “It’s raining in the basement!” Making matters worse, this was a 2-story home with a second-floor laundry room! By the time Mom and Dad got home, their drywall ceiling was little more than white mush soaking into their brand-new wood kitchen floors. At least the basement wasn’t finished! A few days later they had a water leak detection system with wireless sensors which, if they got wet, would shut the water off to the entire house. At worst they would have a small puddle to wipe up. Lesson learned – the hard way.

Further complicating the situation, all four of the kids and that Mom suffered from asthma. They had prioritized wellness and spent extra money on low-VOC materials and a high-performance air purification system. After having baseboards torn off, drywall cut out, and running huge fans to dry things out, the owners’ concerns turned to mold. Fortunately,  this was a one-time event and things dried out properly. Mold tends to thrive in high humidity and areas which repeatedly get wet, such as bathrooms.

While most people’s thoughts turn to the conservation of natural resources when hearing “high-performance home”, the National Association of Home Builders (NAHB) recognized “wellness” as an essential element of building such a home.  Our last post looked primarily at indoor air quality and your wellness. The NAHB further identified mold prevention and natural light levels as essential aspects of wellness.

High Performance Homes - Wellness Pt 2

Remove excess humidity in the home

Bathing and showering release lots of water into the air, just look at your steamed-over mirrors! For your family’s wellness as well as to prevent damage to your home, that excess humidity needs to be removed. Opening a bathroom window can do the trick, but a year-round solution is having a properly-sized bathroom exhaust fan vented directly to the outside (not just up into the attic where the moisture can accumulate and cause problems undetected.) Bathroom ventilation fans are rated in cubic feet of air moved per minute (CFM), so to choose the right size fan, first figure your bathroom’s size by multiplying your bathroom’s length x width x height. Divide that number by 60 minutes, and then finally multiply by 8, the suggested number of air changes per hour for a bathroom.

If you were sizing a fan for the Bonham plan 42239V Suite’s bathroom:

  • 15’-5”L x 9’-8”W x 9’H = 1342 cubic feet
  • 1342 ÷ 60 = 22.4
  • 4 x 8 = 179

Therefore, you would look for a bathroom fan rated for at least 179 CFM. Also, consider the fan’s sound rating. While some fans are so quiet you won’t hear them running, others are annoyingly loud. You’ll recall, quiet, addressed in the first post in this series, is another aspect of a high-performance home.

As with a bathroom vent fan that merely ducts the humidity into an attic, water regularly accumulating somewhere you’re not likely to see is a recipe for mold problems. That’s why homes should be built with a moisture barrier such as housewrap products on the outside of the home, helping prevent water from seeping through the siding materials. Similarly, the roof felt under your shingles helps keep water from leaking into your attic, repeatedly wetting the wood framing members and creating an environment for mold growth.

42239V_Bonham 1clKO

Did you know air conditioning’s original purpose was dehumidification – not cooling? Your home’s HVAC system plays an important role in establishing healthy overall levels of humidity in your home. Your AC helps remove humidity from warm, moist summertime air, as the air coming out of your air conditioner is much drier. You may also have a humidifier integrated into your furnace system to add humidity to cold, dry, wintertime air, helping you avoid dry, scratchy throats and similar discomforts.

Ecobee’s smart thermostats make it easy to control your home’s humidity levels as well as temperatures in your home. www.ecobee.com

 

Ecobee Smart Thermostat

Increase daylight

Our former blog post, Designing With Natural Light, looked at the wonderful aesthetic opportunities afforded by daylight in your home. As seen in the sidebar, there is also an increasing understanding of health-related issues associated with sunlight.

The Bonham design’s eating area and Suite bedroom illustrate a desirable amenity – windows on two sides of the room for increased levels of natural light from two directions. A high transom window helps illuminate the bathroom, reducing eyestrain and the frustration associated with how different light bulbs render makeup colors differently. Also, there’s a window in the walk-in closet which provides a parallel benefit, making it easier to discern navy blue from black.

Single-wide windows in bedrooms 2 and 3 of the Bonham design meet building code requirements for egress, but the double-wide windows provide twice as much sunlight. The number of windows, their size, and placement, along with your home’s orientation to the sun, are key factors to consider. Of course, energy efficiency is a prime consideration when looking at high-performance windows. Opposite of insulation R-values in which higher numbers mean better insulating properties, window performance is measured in U-factors, in which lower numbers indicate better insulation.

SunlightWellnessChart

Covered porches are very popular as they provide cool shade as well as shelter from the rain, but they also cut down the amount of sunlight making its way into the Great Room. Skylights to the rescue! Denoted by the dashed red lines, sunlight streams through three skylights in the Bonham’s Great Room filling your open entertaining area with natural light, creating a delightful, sunny place in this home for everyone to enjoy. A skylight is also suggested in the home’s interior laundry room where no window is possible, easing the frustration of poor lighting common with windowless areas in the home.

First, we examined high-performance homes in terms of comfort. Then how they can contribute to your overall wellness. Join us next time as we turn to the NAHB’s other aspects of high-performance home building – efficient use of water and energy.

For more resources on thoughtful design and products:

High-Performance Homes – Wellness

High-Performance Homes – Wellness

Your Indoor Air Quality Is Nothing To Sneeze At!

Feeling good…feels so good! When there’s no more cough or runny nose, your energy’s back, you’re no longer so irritable or depressed – this is how life is supposed to be!

Still, we rarely notice or appreciate feeling good until we recover from some illness or injury. After the doctor visits, the medicines, and the suffering subsides. Doesn’t it seem that “health care” in our society is really “sick care”? Most of the emphasis, attention, and dollars are placed on helping you recover from (or cope with) whatever ails you. Where’s the “wellness” in health and wellness?

Wellness begins at home, where we spend so much of our lives. The National Association of Home Builders even recognized wellness as an essential aspect of a “high-performance home.” Let’s take a closer look at how your home is built affects your overall wellness.

High Performance Homes - Wellness Pt 1

Healthier Air

In our last post discussing your comfort, we covered the importance of building a fairly airtight home. Effective air sealing and insulation is great when it comes to maintaining desired temperatures, eliminating drafts, and reducing energy consumption, but can also trap indoor pollutants and allergens. Therefore, bringing a controlled amount of outside air into the home and expelling an equal amount of potentially stale indoor air are essential for your family’s health.

Energy Recovery Ventilators (ERVs) not only exchange indoor air, excess moisture, and airborne pollutants for fresh outside air, they also extract much of your warm wintertime indoor air’s heat to pre-warm the incoming colder outside air. During the summer the reverse happens – heat and humidity is extracted from the incoming outdoor warm air, making the ERVs an essential component for both Indoor Air Quality and energy efficiency. While numerous ERVs are available, Broan’s AI Series ERVs offer easy-to-use, intuitive controls or you can choose to let the ERV continually monitor temperature, indoor air quality, and pressure, adjusting in real-time to deliver optimal air quality – all on its own. The ERVs even come with high-performance filters to clean the incoming air.

Air filtration and air purification products can be complementary, but they are not the same.  Air filtration has the goal of trapping airborne particles, from dust and other allergens to viruses, adding to your wellness.  As part of a typical HVAC system, an air filter’s effectiveness at trapping particles is reported as its MERV rating, with the higher MERV-rated filters better at catching smaller and smaller particles you don’t want floating around. Cheaper, disposable air filters, typically 1-inch thick, have MERV ratings typically around 5-8. MERV 9-12 filters are often thicker, sliding into specially-designed housings. Filters with MERV 13-16 ratings are usually thicker and often pleated, providing more filtration area. The American Society of Heating, Refrigeration and Air Conditioning (ASHRAE, which created the MERV rating system), recommends MERV 13-14 for residential HVAC systems, but generally, the higher the MERV rating, the more restricted the airflow. Therefore, you need to make sure your HVAC system is designed with more restrictive air filtration in mind. Otherwise, a high MERV-rated filter will make your furnace fan work harder/longer, using more energy and shortening equipment life.

Air Filter MERV effectiveness

Peace and Quiet

Volatile Organic Compounds (VOCs) can be particularly problematic for individuals suffering from asthma, allergies, or chemical sensitivities. Paints, carpeting and other flooring materials/finishes, and composite wood products (often found in your home’s trim and cabinetry) off-gas VOCs, especially when they are new. Low-VOC product options are often available, and care in choosing these options can positively affect your wellness. Air purification has the objective of cleaning and sanitizing the air in your home. Most often this is accomplished with UV light to destroy microorganisms, VOCs, bacteria, and some viruses. If you have household members dealing with asthma or allergies, an air purifier can make a huge difference in their wellness. You may even find yourself spending less on rescue and maintenance medications! HVAC products which combine both high-performance air filtration and purification are available. Talk with your builder and/or the HVAC contractor about the solution that’s best for you.

Sometimes dinner’s aroma makes your mouth water. And at other times the smells can be unwelcome and overpowering. Removing cooking odors from open, entertaining areas is one of the reasons for the popularity of work-in kitchens. However, most new home designs don’t offer that amenity. The next-best solution for removing cooking odors, grease, smoke, as well as excess heat and humidity is a kitchen exhaust fan/range hood, vented directly outside (not just up into the attic).  How big of a fan do you need?  With the recommendation of exchanging all of the air in the kitchen 15 times per hour or every 4 minutes, that was fairly easy to calculate when kitchens were more defined.

Oakridge Great Room

The Oakridge’s 16-foot 3-inch by 13-foot kitchen at left had an 8-foot high ceiling. 16.25 x 13 x 8 = 1690 cubic feet, ÷ 4 = 422.5 cubic feet of air per minute (CFM), the suggested range hood fan size. But what about open kitchen layouts such as the Markham Ridge plan at right? There’s a rule of thumb that you want a minimum of 100 CFM fan size for every 12-inches of stove width, which would call for a minimum 250 CFM range hood. But that same rule of thumb suggests 150 CFM per 12-inches of width if the cooktop is in an island rather than against a wall because of its openness (minimum 375 CFM fan) – a more appropriate measure for open floor plans.

Markham Ridge Family Room

Another consideration is fan noise.  Opting for a larger fan than what these rules of thumb suggest, operating at a lower speed, might be a quieter solution that contributes to your wellness.

Our Her Home Inspirations emails and blog posts are all about helping you make wise, informed decisions regarding your new home’s design and the products used. And that includes wellness – not as an afterthought, but as a priority! We’ll finish up the discussion on wellness in our next post, where we look at moisture issues (especially mold), and the importance of natural light.

For more resources on thoughtful design and products:

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