· Tropical Green Building Tour·
If you look through a list of green building techniques or LEED certification requirements, you’ll see how few of them apply in the beach areas of Costa Rica. There are many reasons for this, but it’s primarily due to the fact that construction techniques are quite different. Building green doesn’t just mean solar power and windmills on the roof – it also is about low maintenance, and using local know-how for construction and repairs, the idea being to keep your money in your community, rather than hiring outside contractors. Also, the climate here is doubly harsh in that it’s tropical and rainy half the year and desert-dry the other half. Your house has to withstand both seasons. Looking online, you will find very little information out there about how to “build green” in the “dry tropical forest” of the pacific coast of Costa Rica, where much of the construction is going on now. We are trailblazing the way, helping to provide information for others to follow. Please enjoy this webpage – we hope it will help you with your house, and we welcome your comments and suggestions, so we can continually update and improve this information.
Extended shade roofs
Probably the most important green-building consideration is to create lots of shade by building extended roof eaves. A wrap-around porch on the west, south, and east sides of the house will block the sun from heating up the house. These extended roofs create large outdoor living spaces underneath, which are ideal for tropical living, since you will probably spend a lot of your time outside anyway. Covered outdoor spaces are also cheaper to build, so it’s a great investment to add extra space for less money. Every house should have a covered deck space large enough to hold at least a dinner table and a couple of hammocks. If it’s designed properly, you will not need air conditioning in your house because it wont heat up much.
After shade, ventilation is the next most important factor when considering the design of an eco-house in the tropics. Place windows on as many walls as possible, so breezes can blow through from any direction. You can install inexpensive windows that have both sliding glass and screen panels, to maximize air flow when fully open, or to prevent bugs from entering using the screens during times when there are lots of bugs, such as at dusk, or right after the first rains. Houses should also include ceiling fans for additional cooling and air circulation. Fans not only cool, but they also keep a room dry, by helping to evaporate moisture, which reduces fungus and maintenance. We recommend a cheap white panasonic fan that can be purchased and repaired locally. In more temperate climates, houses can be more effectively cooled using good ventilation than using “thermal mass” techniques, that is, heavy walls that absorb heat and radiate it back out at night. That’s because at night, the temperature in the tropics doesn’t drop very much.
I have an extensive article about using airflow in green building here: http://www.airflowandshade.com/air-flow-in-green-building/
By using intelligent architectural design, you will rarely or never need to turn on a light during the daytime. Houses can incorporate glass blocks mounted in the ceilings and walls to project natural sunlight into dark corners, while maintaining structural support. Clerestory windows and light tunnels, such as the “Solatube” brand now sold in San Jose, can be added to some designs to provide additional light.
The light bulbs in the house should of course be long-lasting, low-wattage compact-fluorescents, or LEDs and can be be strategically placed, with individual switches, so you can have light exactly where you need it, rather than wastefully illuminating an entire house or room. Especially if all your power comes from solar panels, you can design your house to make conservation easier.
Many people who move to Costa Rica find themselves going to bed earlier, and rising earlier as well, following the natural light cycle of the sun, so typically less power for your lights is needed here anyway. All ceilings should be painted white, and floors also can be light colored to help keep rooms illuminated with less power. For daytime illumination, of course having plenty of windows is key.
Solar power is rapidly improving and becoming more cost effective. The next few years we will see dramatic changes, making solar power more common worldwide. In the tropics, house designs, appliances, and lighting should be chosen so as to use very little energy, so not as many solar panels and lead batteries are needed. Unless you’re prepared to spend a fortune, living with solar power requires some small changes in your lifestyle and energy use, especially on cloudy or rainy days, when solar panels produce less power (or none.) Many people opt for “solar assisted” power, by using city power as a backup for when their solar panels aren’t generating enough.
More on Costa Rica Solar Power here: http://www.airflowandshade.com/solar-power-costa-rica/
Here’s a partial list of solar power suppliers: http://www.airflowandshade.com/costa-rica-solar-power-suppliers/
Using Waste Heat to Dry Clothes
On the side of the house, you can add a small room with a transparent ceiling and walls, which holds your clothes washing machine and solar power system (batteries, inverter, and transformer, all of which produce waste heat. In the humid conditions of Costa Rica’s tropics, such a hot room will also dry the air. You will be able to dry your clothes on a series of parallel clotheslines without using any additional power, even on the coolest, cloudy days. And by the way, your washing machine can use one of several locally-available biodegradable detergents such as the “Rinso” brand, which aren’t any more expensive than regular detergents.
Living Plants for Shade
One of the best ways to keep a house cool and beautiful is to create natural shade with plants. Planting a tree next to your house can cause future problems such as the roots damaging the foundation, or a windstorm knocking it over on your roof. Instead you can install a trellis system that protects a cement wall from the sun, or a trellis over your entire roof. Several vines can be used to provide fruit – Passion Fruit, Kiwis, and Grapes. Also, vines that attract butterflies and hummingbirds can be planted, including a vine that is the favorite of Costa Rica’s famous “Blue Morpho” butterflies. The roof underneath the dome-trellis can be painted white, to reflect the light that does get through. Not only is this roof functional, but it’s incredibly beautiful and provides a great environment for meditation, yoga, or just having a morning cup of coffee. Some vines can be messy – shedding a lot of leaves, flowers or fruit, but there are alternatives with large leaves that never fall off, minimizing your maintenance.
Here’s articles about using plants on your walls to cool the house: http://www.airflowandshade.com/living-walls-for-cooling-and-beauty/
Here’s an article about using trees to shade/cool your house. Lots to be aware of here: http://www.airflowandshade.com/trees/
A Flat, Usable Roof
Green builders and permaculturists often talk about “stacking functions”, which means using a single part of the house for multiple functions. A flat roof will provide extra outdoor living space for your enjoyment. The roof will become one of your favorite spots, with your best views, an herb garden, a chill space, star-gazing, etc. The white color will keep the roof cool and the vine-covered trellis above will create a feeling of great tranquility as well as providing fruit. A flat roof must be built extremely carefully to prevent rainwater leakage into the rooms below, with a noticeable inclination so that water easily runs off.
Recycled Roofing Material
We were happy to discover a roofing supply maker who uses 100% recycled plastic for their product. We also found a company that makes faux-wood beams and boards from recycled plastic, that are ideal for outside use since they are impervious to insects and rot. Costa Rica doesn’t have many building products made from recycled materials. We are proud to support these businesses and hope to encourage others to follow their leadership. Tinted a natural shade of green, these recycled plastic roofs will be lightweight as well, and last for decades. And unlike ceramic tile roofs, they can be walked on without breaking the tiles, making maintenance easier. Last, but not least, a plastic roof is QUIET… if you haven’t heard the tropical rain hitting a metal roof then you will be shocked at how loud it can be.
December through April is the dry season for the pacific coast of Costa Rica, at which time the area has a desert-like climate with nearly no rainfall. Many streams dry and wells go dry. It’s a great idea to build your house to include a system to channel the water that falls on the roofs through a series of gutters and pipes to a large underground cistern. The water that typically falls on this amount of roof in the rainy season is enough to provide all the water needed throughout the dry season, if you can store that much. The water in the cistern can be purified by a system using ultraviolet light that kills bacteria. In rainy season, you won’t need any water at all except that which you catch from your roof, but in dry season, it’s difficult to store enough to last for months unless you’re really good at conserving or build a huge tank… a tank which could be as large as a swimming pool. Your tank can also be useful in that the top can be used as your deck/patio, and that mass of water, cooled by the earth below, will help to keep your house cool as well.
Since the lots are only 1/4 acre average size, we’re encouraging the owners to use natural colors that help them blend into the natural environment. which will also create a feeling of privacy and consistency. The houses can be colored in natural shades of green and wood/earth tones, which will also create a lush and luxuriant look. Our intention is to create a community with a feeling of great serenity and peace, harmonized with nature. These colors, combined with the living roof and trellis systems, will make the structures look as if they’re a part of the native jungle. Click here for some samples of green eco houses.
Chemical Free Wall Treatments
A key part of Green Building is to minimize the use of toxic chemicals, which often “outgas”, meaning that they release chemicals into the air over time. This is more a problem in closed homes with recirculating air conditioning, or homes shut all the time in winter. A green home in Costa Rica should have lots of ventilation anyway, but we still want to reduce the use of toxic chemicals. Besides the chemicals used in the home, there’s toxicity associated with the production of those chemicals, and the residue leftover in the cans, plus what evaporates into the air and what inevitably ends up in your soil during the construction process. You can avoid much of the “toxic box” syndrome of many U.S. houses from plastics, paints, varnishes, carpets, formaldehyde-infused wood, and other materials that are commonly used in ordinary construction. There is a local (Costa Rican) producer of chemical-free stuccos for both the inside and outside walls of all the houses. Stuccos are also superior to paint because they don’t have to be re-applied every couple years. For the inside walls, we recommend using a shiny-polished stucco that makes maintenance a snap – just wipe it down with a sponge, and it lasts for years without repainting. Remember, an eco-house in not just about low energy, it should be about easy maintenance so you’re spending your life with your family and friends, not cleaning and repairing.
Local Materials Use
A large part of sustainable building and design is supporting your local community and its economy whenever possible. By spending locally, you keep your money in circulation at home, benefiting you, your family, friends, and neighbors. Wal-Mart and other national brand stores are cheap, but there’s a heavy price to pay in the long-term when so much of the money spent in your town gets sucked out by chain stores. Commit to using local materials such as teak and melina wood, grown and milled locally. Use local architects, builders, and workers, and shop in town for your fixtures and appliances. Local hardware stores can order much of what you’ll find in San Jose.
Thinking about building in bamboo? Unfortunately we don’t have any LOCAL suppliers of treated construction-grade bamboo, but there are good suppliers in other parts of Costa Rica. Bamboo is one of the most beautiful materials to build with in the world, and it’s very strong under certain conditions, but like everything else, there are trade-offs. Read more about bamboo here: http://www.airflowandshade.com/green-building-with-bamboo/
Hire Local Craftspeople
In addition to the materials themselves, we urge you to find and hire local crafts-makers to produce the furniture, windows, decks, cabinets, and other things that are needed in your house. Instead of buying a metal toilet paper holder made in China, you could have one made by a local metal worker, made from locally grown wood or bamboo. There are several excellent carpenters, both Ticos and foreigners, living in the area. They will use local wood to produce almost any type of furniture that you want. Just cut out a photo from a catalog and take it to them, and they will most likely be able to duplicate it for a fraction of the price. You can also use their wood shavings and sawdust from them as mulch for your plants.
Outdoor Garden Bathroom
This trick is one of our favorites that everyone loves. Not only is it beautiful, but it’s a great investment as part of your house. If you like you can keep the toilet and sink inside, but the shower, which produces heat and humidity, is kept outside in a private garden. Chemical-free, biodegradable shampoos and soaps, such as those made by Costa Rica’s own “Bioland” company, can be purchased locally and should be used. Keep in mind the long-term damage that occurs when hundreds of households are all dumping chemicals into their soil, year after year. In many places in the U.S., soils around people’s houses have so much poison in them, they qualify as toxic waste. Most regular soaps and shampoos contain chemicals such as phosphates that end up in streams and can do long-term damage to the eco-system.
There are many ways to treat the waste that flushes down your toilet. Normally, here in Costa Rica, a simple septic tank is used. A locally available liquid called “EM” (Environmental Microbes) can be flushed into the toilet and contains bacteria that speed up the process that breaks the waste into harmless matter. No harmful chemicals, especially chlorox and other bleach-type cleaners, should be used in these systems because they kill the beneficial bacteria. Vinegar is a great alternative to use as a cleanser, and so is lime or other citrus. The local cooperativa sells a lemon-based liquid cleanser called Limonoil, made by a Costa Rica company called Agrocosta, which is ideal for cleaning toilets and sinks that flow into a septic tank. Hotels such as Amor de Mar in Montezuma have trained their staff to use this cleaner, along with EM, to great success.
A better alternative to a normal septic tank is a dual-tank septic sytem which separates liquids from solid. Or better yet, a three tank mini-sewage treatment plant. These start at around $5000 and there are several varieties, usually imported from Europe.
The average American uses approximately 70 gallons of water per day. The average volume of drinking water flushed down an old-style toilet in America with every push of the handle is equal to the entire daily water use of a family in some countries in Africa. By simply adding low-flow showerheads, faucets, and a dual-flush toilet, it cuts water use in half, without other conservation efforts. Dual flush toilets are available in the local hardware store in Cobano, and have two different flush buttons on top – one for if you go “#1” and one for “#2”. Another great innovation is to design your bathroom so that water from your shower or sink is recycled to use a second time for flushing your toilet.
Integrated recycling & composting
The kitchen area, can be designed to aid in separating and storing compost, recyclable materials, and trash. These materials can be stored outside the house, keeping ants and other bugs as well as bad odors from inside the kitchen area. If you tend to eat mostly vegetarian, healthy foods, you can run your kitchen sink water straight out into the gardens, and throw food waste out the kitchen window, which mulches the plants. If you eat a lot of meat, you should dispose of it farther from the house. Currently, recycling in the Montezuma area isn’t great. A program, started by the Amigos de Montezuma community group, helps to recycle plastic and metal such as tin and aluminum cans. Currently, no one has found a way to recycle glass, so it ends up in the landfill in Cobano. Efforts are being made to find someone who will haul out the glass or reuse it.
Many good eco-house designs have extra high ceilings to make the living space more beautiful, cool, and light. An additional benefit is that you can often incorporate a loft space. These lofts are great for storage, or if they’re large enough, can be used as a spare bedroom for guests. Kids of course love lofts. Packing more living into a smaller space is a key principle of green building, so less materials are needed to construct the house.
We welcome comments and suggestions about our ideas about tropical green building. We are constantly improving this site as new products become available, and new ideas are brought to our attention. Please contact us if you would like to participate in this.
— Geoff McCabe, Pura Vida Sunsets