This article was originally published on Houzz on Feb. 28, 2014, as "How to Add a Solar Water Heater," and is presented here with permission. Read the original article

As people increasingly build better houses, with more efficient envelopes and lower energy consumption and waste, a greater percentage of the energy we do use is going toward heating water. In fact, in a Passive House and many LEED-certified houses, heating water for residential use is the primary energy demand.

As a result, in Europe, many local and national laws now require that a certain percentage of residential hot water be heated by renewable energy. A solar water heater is one way to meet that requirement without dipping too far into savings or renovating an entire system.

Let’s look at some of the basics to consider when adding your own solar water heater.

Photo credit: Metro Solar; original photo on Houzz.

Project: Installing a solar thermal panel to provide hot water for residential use (either to be used right away or as part of a hydronic radiant heating system), through an indirect circulation system.

I am only going to talk about indirect circulation systems here for a few reasons. Indirect systems use a special fluid in the actual solar thermal panel. This fluid heats up and then passes through a heat exchanger, transferring the heat to the potable water you end up using. These systems are generally more efficient and resistant to freezing temperatures than direct systems. The fluid never mixes with your potable water, helps prevent corrosion in the pipes of the system and can carry more heat with it.

It’s a good project for you if: You’re looking for a system that does not involve intensive home remodeling. A solar water heater can be added to an existing system with relative ease, as long as the installer is experienced in this particular kind of system.

Photo credit: Arkin Tilt Architects; original photo on Houzz.

Who to hire: A specialty plumber or contractor with experience in solar water heaters. Be careful in choosing your installer. This is a system that if poorly installed can cause serious problems (including leaks in your roof). Ask for references and examples of work.

Cost range: Although installation costs differ depending on the project, you should set aside $7,000 to $10,000. That seems like a large chunk of money, but can usually expect to see big savings immediately. The U.S. Department of Energy estimates that monthly bills drop by 50 to 80 percent after a solar water heater is installed. An excellent page on its website can help you estimate initial costs and the payback of a solar water heating system. In the U.S., also check DSIRE, a database of state and national incentives that could help speed up payback.

Typical project length: As long as you don’t have to adjust the structure of the house or add space for the mechanical room (where the tanks and systems are stored), the installation of a solar hot water system and its components shouldn’t take much more than a week, and sometimes less.

Best time to do this project: Any time your roof isn’t covered in snow. Start planning now for an installer to come out to your house when spring hits.

Photo credit: Metro Solar; original photo on Houzz.

What to expect: This is what a typical mechanical room looks like. The large tank is the hot-water storage tank, with the pipes running down from the roof panel installation. Also notice the expansion vessel (the small white tank on the floor). The expansion vessel allows the fluid to expand without cracking the pipes.

There should also be a safety valve (not visible here) that discharges the fluid of the system in case the expansion vessel is not sufficient in an emergency.

Photo credit: Paulsen Construction Services, LLC; original photo on Houzz.

Here you can see the hot-water storage tank on the right, with the expansion vessel on top of it. The red fixture in the middle is the circulation pump, which keeps the fluid moving.

Notice that all the pipes are insulated. The fluid inside the pipes can reach temperatures above 212 degrees Fahrenheit (100 degrees Celsius), so it is essential that the pipes are physically removed from the rest of the system and insulated sufficiently. If the structure of your house is wood or contains flammable insulation, such as wood fiber, you need to pay special attention to the protection and placement of the pipes to avoid a fire hazard.

Photo credit: Solar Hot Water; original photo on Houzz.

Here is a system that shows an integration with a gas burner. Depending on the location, climate and season, the preheated water from the solar panel may not meet all of the home’s hot-water needs. This booster ensures hot water even when the panel has reached its limit.

Photo credit: Aneka Interiors, Inc.; original photo on Houzz.

First steps: Do your research and decide which solar water heater system will work best for your needs. Will you be attaching the system to a radiant heating system, for example?

If you need help getting your head around the situation, ask a green building professional or an experienced architect or contractor for a design consultation. A pro can help you determine which part of your roof is the best location for the solar thermal panel. (It will be oriented toward the equator for optimal solar radiation.)

You can also browse Energy Star–rated water heaters to start getting a better idea of costs before asking for quotes.

Related articles

On Fridays, USGBC shares green home-related content curated from around the web. If you see a great article on aspects of environmentally friendly home living such as green building, renovation, energy use or cleaning, please send it our way.

See more ways to go eco-friendly with home decor

Whether you are a current renter or are searching for a new apartment or rental home, you might wonder how you can implement sustainable strategies in a space you don't own. The good news is that there are plenty of simple ways to green your home as a renter, from lowering the thermostat to setting out plants, and if you're looking for a building that's already eco-friendly in design, you'll find that more and more options are coming on the market.

Finding a green place to rent

As green buildings become increasingly desirable in the real estate market, both new construction and adaptive reuse projects are luring renters with energy-efficient features.

Look for properties that offer not only the basics of efficient appliances and lighting within individual units, but also features that benefit the whole community, such as solar panels, amenities for bicycle parking or landscaping that conserves water and uses native plants.

There are plenty of examples of places like this. Atlanta apartment complex Ponce Park recently earned LEED Platinum status for its 305-unit complex, which uses Energy Star appliances. In Watervliet, New York, the Tilley Lofts project also achieved LEED Platinum for their update of a historic warehouse into 62 loft-style apartments. The LEED Gold Goldtex Apartments in Philadelphia run on wind power, and in San Jose, California, Gish Apartments earned LEED Gold for their affordable housing that combines green features with community assistance programs.

The 2015 LEED Homes Project of the Year, The Woodlawn apartments in Portland, Oregon, offers renters a green roof, green wall and a 9,000-gallon rainwater cistern for irrigation in addition to the unit features.

Find a green apartment complex in your area by exploring the LEED project directory, starting with LEED BD+C Multifamily Midrise. You can also peruse online listings in your own locality, such as this resource for New York City apartments that are seeking or have already achieved LEED certification.

Making your current spot greener

Before you sign the lease, you can negotiate with the property owner about making upgrades to the space before you move in, such as installing more energy-efficient appliances, inserting weatherstripping around windows and doors or using low-VOC paint for the repainting that is typically done between tenant occupancies.

Once you've moved in, you can do many of the same daily things that homeowners do to recycle, reduce your energy use and enhance indoor air quality:

  • Consider conducting a DIY home energy audit or bringing in a professional to assess where you're expending a lot of energy, than make adjustments such as turning your refrigerator and freezer to the proper temperature settings, only doing laundry when you have a full load to wash or turning down the heat when you leave for work.
  • Enhance your home's biophilic appeal, as well as its oxygen levels, by adding plants to your rooms.
  • Try home composting. It's easier than you might think, and goes a long way toward reducing landfill waste.
  • You're probably on top of tossing items into that blue bin, but explore other aspects of recycling through donation, upcycling and electronics disposal.

Subscribe to email updates from Green Home Guide

Floors have a long-term impact on indoor air quality and a home’s look, feel and functionality, since they typically account for the most space in a residence.

Installation and maintenance of flooring can require a large quantity of raw materials, finishes, adhesives and cleaners, but there is a wide array of materials to choose from in today’s market that are environmentally responsible. Finding the right one depends on your needs and aesthetic preference.

To make your decision easier and to help narrow down your choices, here are four factors to keep in mind when looking for flooring material that’s both sustainable and healthy.

1) Think about the raw materials and how they were manufactured.

Your flooring material ideally should derive from a renewable resource, such as wood or bamboo, both of which are made from plants. How wood or bamboo is harvested is important, though, since both can be cultivated in environmentally destructive ways. Look out for ones that are certified by the Forest Stewardship Council

Additionally, consider using refurbished stone and tile recovered from existing structures or recycled/partially recycled materials, such as rubber flooring made from used automobile tires. Although these have associated mechanical energy costs, they require fewer new resources.

Generally, it’s better if the material needs minimal modification during the manufacturing process. Stone, wood and bamboo require the least modification, while cork, ceramic tile, linoleum, rubber flooring and carpet require more energy to manufacture.

Review our buyer’s guide for a roundup of eight types of eco-friendly flooring materials.

2) How much transportation will it take for your materials to get to your home?

Consider using materials that have been extracted or harvested near your home to help lessen the environmental impacts of transportation. (For more, review the Materials and Resources credit category in the LEED v4 Building Design + Construction Guide).

For example, materials such as Asian bamboo have to be shipped from great distances, increasing their total environmental impact and embodied energy costs (the sum of all energy required to produce any goods or service).

3) Consider each room’s use and estimated foot traffic.

If you expect a particular space, such as a living room, to see more use in your household, it might be worth exploring installing a flooring material that’s more resilient and requires less maintenance.

A less durable floor likely will need to be replaced more often. The need to frequently clean and polish a more high-maintenance floor could potentially expose occupants to more harmful chemicals. Stone requires frequent refinishing, while linoleum requires little to none.

Read about USGBC’s web and graphic designer Amy Hedgepeth's experience in choosing environmentally responsible flooring.

4) Think about the material’s installation process and disposal.

Installing flooring could require a variety of activities—cutting, sanding and sealing—that could affect indoor air quality, so it's important to consider what the installation process will be like for your flooring.

It's also worth noting what will happen to the flooring material after you’re finished with it. For example, linoleum, cork and wood are biodegradable or can be burned for energy. 

Explore more flooring articles

On Fridays, USGBC shares green home-related content curated from around the web. If you see a great article on aspects of environmentally friendly home living such as green building, renovation, energy use or cleaning, please send it our way.

Windows, doors and skylights have a big effect on the energy efficiency of your home, as well as providing you with views and fresh air. Check out these blog articles on finding the right ones for your living space.

Learn more about home energy efficiency

It's easy to be more sustainable with how you use and store food. According to the EPA, about 95 percent of our food waste ends up in landfills. You can reduce food waste by buying strategically for your family's needs and storing it properly.

In addition, it's better for the environment and for your family's health to use storage containers that are nontoxic and long-lasting. Plastic bags can take up to 1,000 years to biodegrade. Plastic containers often contain BPA, the risk of which grows when we heat the plastic (as happens in the microwave or dishwasher). 

Buying and cooking

Wasting less food starts with shopping smart. Create a meal plan or list of foods you or your family usually consume in a week, and buy those. If you often end up with more fruits and vegetables than you can use while they're fresh, consider shopping more frequently but in smaller amounts.

Chop up a week's worth of produce items, so they're ready to go when needed—it will make it less likely they'll languish in the fridge and spoil. Take it one step further and prepare entire dishes in advance, refrigerating or freezing them to eat later on.

Learn to adapt recipes or improvise your own, based on what's in the house right now. Use up leftovers and veggies by creating your own soups, salads or casseroles from available ingredients. Who knows—you might end up inventing the next favorite family recipe.

The fridge and freezer

There are plenty of long-lasting alternatives to plastic refrigerator containers. In the mid-20th century, people used glass refrigerator dishes in fun matching sets. They're still around, if you're into the vintage look. Today, you can also store your items in myriad glass, ceramic or stainless steel containers to avoid using plastic.

Freezing groceries reduces food waste and allows you to buy in bulk, but make sure you don't then fill your freezer with items wrapped in plastic. A greener choice would be to use mason jars or empty milk and juice cartons. If you use glass, reduce the risk of cracking by choosing containers that are relatively thick, and allow the contents to freeze before putting on the lid.

Portable snack bags

Many of us are used to packing school lunches or office-to-gym snacks in plastic sandwich bags. But that adds up to a lot of waste, even if you reuse each one a few times. Of course, you can use glass, steel or BPA-free plastic containers for food, but if you want a lightweight option for hauling around all day, try reusable snack bags.

Many companies make cloth snack bags that are easy to wipe clean or even throw into the washing machine. See this article from Kitchen Stewardship for a rundown of some of the options, with photos and reviews of each.

See more quick tips on green household practices

On Fridays, USGBC shares green home-related content curated from around the web. If you see a great article on aspects of environmentally friendly home living such as green building, renovation, energy use or cleaning, please send it our way.

  • In "Getting Down to Zero," Your Home Source counts down seven ways, from a south-oriented site to smart appliances, to build or retrofit a home to net zero energy standards.
  • Reducing food waste does as much for the world as it does for your monthly budget. Read these tips from the U.S. EPA on "Reducing Wasted Food at Home," including menu planning, storage and portion sizes.

  • Speaking of reducing waste, water consumption is an area that can easily get away from a homeowner. Check out 10 ideas for conserving water in your home from the Eartheasy blog.

Look at ways to reduce your kitchen water use

This article was originally published on Houzz on Aug. 15, 2013, as "Championing the Solar House, From the 1930s to Today," and is presented here with permission. Read the original article

According to author and educator Anthony Denzer, a solar house—one that deliberately uses the energy of the sun for heating spaces—is often thought of as a product of the 1970s: "An eccentrically shaped structure with oversized sloped glass walls and diagonal cedar siding...an earth berm...a Volkswagen van nearby."

He admits that this image isn't completely false, since many architects tackled house designs in that period that would minimize the use of fossil fuels, spurred by the oil and economic crises. But it's an incomplete picture.

Denzer's The Solar House (Rizzoli, 2013) corrects this oversight by tracing the development of solar houses from the 1930s to today. It's a narrow topic, but the book is a fascinating, accessible read. Denzer has crafted a narrative of the architects and engineers who devoted much of their lives to searching for houses that would use less energy, as societal and political currents ebbed and flowed with and against them.

A general story of solar houses could be painted as the conflicting attitudes of two fields: the architects' aesthetic and interest in passive heating versus the engineers' technological and active (mechanistic) focus. This is an area that Denzer spends some time on, and it is an especially important one, considering that we have not reached a reconciliation that might enable more widespread appreciation of solar houses. This is not to say the story is about a duel of two groups. But it is indicative of wider strands in American society—particularly concerns of how things look and how things perform.

The Solar House, original photo on Houzz.

Denzer starts the book with Fred Keck, described as the first solar architect. Keck worked with his brother William in the firm Keck + Keck, designing a number of residences in and around Chicago. Many of them focused on the development of the solar house as a unique type. The characteristics they share are linear east-west plans with large, south-facing windows and roof overhangs to block the high summer sun.

Howard Sloan commissioned Fred to design a prototype solar house in the North Shore Chicago suburb of Glenview in 1940. Sloan opened the house to the public, charging a dime admission to more than 5,000 visitors in four months. He hoped that the comfortable interior on cold winter days would persuade people of the merits of solar houses.

The Solar House, original photo on Houzz.

Keck would continue to work for Sloan, incorporating new materials and technologies (triple-pane glazing to reduce heat loss from inside to outside at night, radiant heating, etc.) in a 24-house subdivision they called Solar Park. Keck had also developed operable and insulated louvers that were often below the south-facing glass; these assemblies allowed for ventilation during the day while helping to maintain the interior temperature at night when closed.

Pictured is the Duncan House in another Chicago suburb, Flossmoor. It included the same elements (linear plan, south-facing windows, roof overhangs) but also exterior "wing walls" with adjustable vertical louvers for cutting down on the late-afternoon sun in the months when overheating of the interior occurred.

The Keck brothers weren't really known for the solar houses they developed in the 1940s (they were omitted from Sigfried Giedion's influential Space, Time and Architecture even though he toured their houses). Instead it was a couple of houses Fred Keck designed for the 1933 Century of Progress fair in Chicago, both glass houses rather than solar. The House of Tomorrow and Crystal House both featured all-glass exterior walls with blinds and curtains, respectively, for shading.

The houses were extremely popular, but their intent and appeal were formal rather than functional; they pointed to an alternative future through the use of glass. But Keck did realize the benefits of solar heating, which led him to develop houses in the next decade with more selective glazing. With so much single-pane glass, the House of Tomorrow would overheat during the day and lose heat at night, something that did not discourage Mies van der Rohe and Philip Johnson from creating inefficient glass houses almost 20 years later.

The solar houses that pepper Denzer's book therefore resemble the 1970s stereotype, rather than glass houses, but they are the 1970s typology in the making. There is a Frank Lloyd Wright "hemicycle" house, a similar but inverted curved house by the Keck brothers, amid work by less-known architects who created houses within academic institutions or for companies that would benefit from the implementation of solar houses. In the latter vein, Libby-Owens-Ford commissioned notable architects to design solar houses for each of the 48 states at the time; in the end only a book of the designs was produced, not the actual houses, but the initial hopes were high.

Architect Henry Wright's renovation of the Ramirez House in Pennsylvania employs the same principles as the Kecks' pioneering work. But its wood floor did not allow for the sun's energy to be stored and released later, as happens in concrete floors. From discussions of the house came a focus on thermal mass as an important part of solar houses.

The Solar House, original photo on Houzz.

Many schools worked on developing solar house designs, particularly MIT, with its numbered series of house designs starting in 1939. As can be seen here, Solar House I, developed by engineer Hoyt Hottel, focused on technology over architecture.

The south-facing roof was covered in flat-plate collectors, or heat traps, which Denzer defines as "a shallow box, consisting of three glass places separated by airspace, a black-painted copper plate backed by copper tubes of water, and 5 1/2 inches of mineral wool insulation." The sun would heat the plates and therefore the water, actively heating the spaces through mechanical means.

The Solar House, original photo on Houzz.

Maria Telkes, an engineer at MIT who developed an alternative scheme to Hottel's, worked with architect Eleanor Raymond on a house with a similar reliance on technology but one whose form and aesthetics would also benefit the design. The Dover Sun House positioned Telkes' collectors (made with phase-change salt in containers behind glass) above south-facing windows, so the occupants would have views and the sun's heat would be stored to heat the interior via bins above the ceiling.

A testament to the popularity of the Dover Sun House, as well as the desire for houses that would use less energy in the postwar years, can be seen in a cover story of Popular Science in 1949. Unfortunately, the system lasted only two years, due to the sedimentation of the solid and liquid salt and the corrosive effects of the element on the bins.

The efforts on the part of engineers and architects developing solar houses in the years before and after World War II culminated in the 1955 World Symposium on Applied Solar Energy and the 1957 Solar Energy exhibition in Greece. So many solar houses were built after 1955 that, as Denzer says, "documentation would be impossible," but it was not enough to stave off the low cost of energy and the rise of air conditioning in those years.

Nevertheless, Denzer presents some novel projects from these years, such as engineer Masanosuke Yanagimachi's Solar House II in Tokyo. The interior looks like that of a traditional Japanese house, with tatami mats and translucent panels, but it also includes radiant ceiling panelsserved by rooftop heat traps, as in Hottel's MIT prototype.

The Solar House, original photo on Houzz.

Yanagimachi's Solar House II is one of the many projects documented in the book with architectural drawings. This building section illustrates how the systems are tied together, from the rooftop heat sink and radiant ceiling panels to the innovative heat storage water tank in the basement.

The latter was used for both heating and cooling; in the case of cooling, the heat pump made ice at night that was used the next day to cool the water pumped through the house. The concept of off-peak ice storage is now increasingly common in green buildings, even in skyscrapers.

 

The Solar House, original photo on Houzz.

Denzer calls the late 1970s a "Solar Renaissance," suitable given that even Jimmy Carter mounted solar hot-water panels atop the White House in 1979 (to be removed by Ronald Reagan seven years later). One of the projects from this time period is Saskatchewan Conservation House, which resembles early solar houses in form but departs from them in important ways: It has smaller and fewer windows, it doesn't rely on most of the engineered technologies from the previous decades, and it is superinsulated. The latter attribute is its most lasting, influencing today's Passivhaus principles and Canada's R-2000 program.

 

The Solar House, original photo on Houzz.

The basic idea of the superinsulated and supertight house is that the heat within the interiors (some of it coming from solar gain) isn't lost to the outside. Fresh air is brought in by an air-to-air heat exchanger, as is the case in the Conservation House. The house performed so well—reaching what would now be referred to as net-zero status—that the solar collectors mounted above the second-floor windows could have been omitted, as they weren't needed for space heating.

The Solar House, original photo on Houzz.

Denzer ends the book with some snapshots of solar houses today. These fall into the superinsulated camp of houses designed to Passivhaus principles, like this 1991 house in Germany by Wolfgang Feist and others, and the biennial Solar Decathlon competitions, in which student teams design and build houses that vie to be the greenest in a number of measured ways. The latter more closely resemble the pioneering work of the Kecks, but the work in the competitions also attempts to synthesize architectural and engineering considerations, arising through multidisciplinary teams and integrated design.

It's clear from Denzer's book that there is more to solar houses than previously understood or imagined. But it's also clear that there is still plenty of work that needs to be done to synthesize the aesthetic and the technological, and to persuade the public that solar houses are viable and desirable.

Rising energy prices may make solar houses more desirable in the years and decades to come, so it's time for architects and engineers to work together on creating solutions that tap into those Denzer so eloquently presents.

Related articles 

The living wall, or green wall, is trending in homes and commercial buildings alike. Besides the sheer biophilic joy of resting your eyes on green growing textures in your living room, a living wall can bring concrete benefits for the homeowner. These include better indoor air quality and insulation from sound, heat and cold. 

Living walls consist of panels filled with plants—grasses, succulents, ferns, vines or mosses, to name a few. The frames may be fashioned from wood, steel, recycled plastic or other materials, depending on your design preference and budget. Some panels are flat, with plants embedded in foam, while others consist of trays that are large enough to contain soil-filled planters.

Photo courtesy of Planted Design.

You also can build on an external wall of your home. As with regular gardens, outdoor green walls can attract bees and butterflies, which improves the local ecosystem. They also help mitigate the temperature fluctuations that lead to building expansion and contraction.

Options to consider when building a green wall:

  • Location of the wall. Building indoors? You might want to position the living wall where it will receive natural light. If the plants are not in an area where they can receive direct light, you will need to create a wall with light fixtures to allow for photosynthesis.
  • Level of maintenance. Some living walls have a built-in watering system to minimize maintenance for the homeowner. Choosing plants that need only infrequent watering also cuts down on this chore. Using non-soil substances, such as clay granules, can deter bugs.
  • Type of plants. You may choose to go with particular species for aesthetic reasons, but also take into account plants that work well for your light levels and climate. If you like, you can even fill your wall with a vertical vegetable or herb garden.

Consulting a professional living wall designer/provider always is an option, or you could do it yourself. To try the look on a smaller scale, upcycle old pallets or picture frames to create fun living art.

Learn more about adding plants to your home

On Fridays, USGBC shares green home-related content curated from around the web. If you see a great article on aspects of environmentally friendly home living such as green building, renovation, energy use or cleaning, please send it our way.

Watch another family's journey in green home building