In my work as an urban planner, I have come across the concept of "green cities" and "green architecture." While I was convinced these were very good concepts, I also got the impression that it is expensive, because of the costly energy-saving technologies that are associated with it, such as solar power systems and heat-reflecting windows. In hindsight, I think this was the reason why I didn't think of adopting the features of "green architecture" for our weekend cottage. We really just wanted to build a small, simple, and inexpensive house that would meet our family's needs for a place to relax, unwind, and commune with nature.
Our cottage is now 10 years old, and since its completion in 2006, we've learned more about green architecture and have gone through a number of changes, including repainting, repairs and replacement of certain components of the structure. These were necessary because for one, we experienced a strong typhoon that destroyed some of our windows; some of the cement fiber boards used for walls and eaves rotted due to the very high moisture content of the mountain air; some parts of the wooden door frames and kitchen counter were eaten by termites; and both the exterior and interior walls faded because of the humid weather brought about by frequent rain showers, and thus needed to be repainted. Throughout all these, we have learned a lot of lessons, many of which have to do with green architecture and construction.
With the growing interest in "green" homes, I thought I should share some the lessons we've learned, mostly by accident, from our "accidental green home."
Working with the Land
The site of our mountain cottage is in the foothills of Mount Mandalagan, which is part of the Northern Negros National Forest. It has a rolling terrain with some steep slopes, and is heavily forested with a lot of old growth trees. It’s at an elevation of about 800 meters above sea level, with a panoramic view of the lowlands and, on clear days, also of Guimaras Strait and Panay Island in the west. We specifically chose the site for its views, although I designed the house to conform with the slopes so that the natural drainage system is preserved to prevent erosion, which usually results when the natural terrain is disturbed. We also chose the area where we didn't have to cut down any tree and, in fact, preserved all those that existed. Preserving old-growth trees not only ensures the soothing ambience of the forest, but also helps prevent erosion and landslides, as well as provides habitat for wildlife including the rare native hornbill.
Our cottage has two bedrooms, two bathrooms, a sleeping loft, an open-concept living-dining-kitchen area, and a veranda looking out to a panoramic view of the lowlands and nearby mountain ranges. The total area of the house is less than 100 square meters, although it looks large from the outside because it's triangular in shape. Each bedroom can squeeze in four people, while the sleeping loft, which is directly above the veranda, can accommodate four to six persons on the floor. It’s just big enough for our family's needs, plus a few friends or relatives who occasionally join us. A small house is a lot easier to clean and maintain. It also has a smaller environmental impact because it doesn't use too much energy and thus is energy-efficient. Milou and I planned our cottage around our lifestyle and kept the space manageable and cost-effective.
Use of Sustainable Materials
Because we were not thinking "green" when we decided to build the cottage, I designed it to use materials that were readily available, easy to maintain, and familiar to local carpenters and other construction workers. It was designed also to be built using the conventional method of reinforced concrete post-and-lintel construction, which is still the cheapest method of construction. Thus, I specified concrete hollow blocks for walls, a steel roof frame (to withstand strong winds as well as termites) with long-span galvanized iron roofing, and reinforced concrete floor slab with plain cement finish. I thought of using bamboo, which grew extensively in the area, but I was worried about its upkeep because of bamboo's tendency to deteriorate due to termites and dry-rot (bukbok) when it's not properly treated. We did build a separate bamboo cabana, but it lasted only three years. There were some large trees that were felled by lightning or typhoons which we were able to use for the kitchen counter, our dining table, and some other furniture including stools and benches. We also used river stones to create the drainage canals along the driveway and around the house. For the driveway, we used the volcanic sand that was readily available in the vicinity of the site. We also just allowed grass to grow on the driveway, thus further enlarging the greenery around the cottage. We realized later that the use of these natural materials that were already available in or near the site reduced the impact of our construction on the environment.
Natural Ventilation and Maximum Sunlight
The prevailing winds on the site are on a north-east/south-west direction throughout the year. The cottage is positioned in such as a manner that the bedrooms, which are on the north and south sides of the cottage, catch the prevailing winds. I provided wall-to-wall jalousie windows for the bedrooms, sleeping loft and the living-dining area, for maximum natural light as well as cross ventilation. Unfortunately, some of the windows needed to be replaced because they were damaged by a strong typhoon a few years ago. I underestimated the strength of the winds and specified a lower grade of window frames, which was unable to withstand the typhoon. But on a more positive note, the positioning of the windows maximized cross-ventilation, which together with the cool mountain air, eliminated the need for air-conditioning. In fact, we even have to wear sweaters and use thick blankets at night especially during the months of October to March. The large windows and the glass sliding doors to the veranda also allow for maximum sunlight, thus reducing our electricity consumption.
When we were building the cottage, there were already double-flush toilets, which we installed in the bathrooms. We bought these because they were on sale, and only realized later that these actually conserve water! We also used LED bulbs for all our lights, which we knew would help make the cottage energy-efficient. We thought of using solar power, but found it too expensive at that time. Being up in the mountains and 40 minutes away from the city, we were also worried about maintenance, should something go wrong with it. Now that solar power systems have become more affordable and popular, we're considering installing it. We also thought of investing in a rainwater harvesting system in order to use rainwater for flushing the toilets and watering the garden. But with our water coming from a spring in the mountains, and the fact that it rains a lot where our cottage is, we feel investing in such a system isn't really necessary, at least for now.
Living with Insects
When we built our cottage, we did not provide for screens on the windows and door openings because these tend to reduce cross-ventilation and make the interior warmer, especially during hot and humid days. However, after we finished the cottage and were having dinner there already, we were "invaded" by a lot of different insects including some pretty large bugs. They were attracted by the interior lights, while the outside was very dark. This forced us to install screens, which somehow affected the rustic look that Milou and I wanted the house to have. But it was the only way we could think of that would allow us to eat dinner without bugs diving into our food. After dinner, our favorite pastime is going out to the veranda to watch the fireflies flying around the nearby avocado tree.
Growing our own Food
The soil on our property is very good. In fact, Milou's mother planted a lot of lanzones trees throughout the lot, together with many other fruit trees including cacao, coconut, bananas, papaya, langka and even batwan, which we are able to harvest quite regularly. Recently, we started planting vegetables such as petchay, lettuce, eggplants and tomatoes. At first, these did not prosper mainly because of worms and insects that ate up the leaves. But we didn't want to use chemical pesticides. We later learned that we could reduce insect and worm infestation by planting tanglad (lemon grass) and marigold near the vegetable patch. It seems there is something with these plants that insects and worms don't like. I tried to teach our caretakers the use of raised beds for vegetable gardening. But they prefer using the more traditional method of planting on the ground directly. We don't really produce that much of the vegetables, but its more than enough for our needs and thus often share the harvest with friends and relatives.
Our experience with these "green" features covers just a few examples of a much wider range of green home ideas. These last ten years have been a learning experience for Milou and me in adapting the principles of a "green" home to our own little mountain cottage. To a large extent, many of the lessons we've learned were unexpected or accidental. As our cottage gets older and our lifestyle continues to change as we ourselves grow older, we are looking forward to learn more in growing greener.
Dinky von Einsiedel was an Area 1 resident from 1952 to 1969, and an alumnus of UP Elementary School, UP High School, and UP College of Architecture. He is a registered Architect and Environmental Planner in the Philippines, and was formerly Regional Director for Asia-Pacific of the United Nations Urban Management Programme. He currently manages his own consulting firm, Consultants for Comprehensive Environmental Planning, Inc. (CONCEP).
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