TROPICAL DESIGNOF AN ARCHITECT CASE STUDY ARC 111 TROPICAL DESIGN
Many confuse the term tropical architecture with a particular design style. Inreality, tropical architecture is all about achieving thermal comfort through theuse of passive design elements like sunshades, cavity walls, lightshelves, overhangs, roof and wall insulation and even shading from large treesto block the sun. It can look very traditional, ultramodern or even high-tech.Tropical architecture is all about tackling urban heat island effect. So whatexactly is the heat island effect? This phenomenon is what results from citiesthat have very little greenery and very many concrete surfaces. The city willhave 2 to 3 degrees Celsius higher temperature than that of the surroundingsuburbs and countryside. Figuratively, it forms an “island” of hotterland, while being surrounded by cooler land in the city outskirts. Dark-coloredroofs add to the heat island effect. Some of the heat absorbed by dark-coloredroofs is transmitted to the room or space below.
THE BELAROCCA ISLAND RESORT IN THE PHILIPPINES AND THE HOUSE IN MAUI, HAWAII CASE STUDY AND DESIGN PRINCIPLES FOR TROPICAL DESIGN ACHIEVEMENT
Basic design principlesFor the Philippines, having a warm humid climate, there are a few basic designprinciples regarding natural ventilation to cool a home or a building. BelaroccaIsland Resort shows the following design principles creating an overall view of atropical island sanctuary.1. The external features of the building envelope and its relation to the site should bedesigned to fully utilize air movement. Interior partitions should not block airmovements.2. Air velocity can be reduced when the interior walls are placed close to the inletopening or each time it is diverted around obstructions.
3. If interior walls are unavoidable, air flow can still be ensured if the partitionshave openings at the lower and upper portions. This is a common strategy in the oldFilipino bahay na bato, with its transom panels covered with intricate wood carvingsor wood louvers.4. Maximize window openings for cross ventilation of internal spaces. Vents in theroof cavity can also be very effective in drawing out heat from the room interiors.5. Since hot air goes upward, and cool air goes downward, openings at the top ofstaircases and in clerestory windows facilitate air change.6. It is generally cooler at night, so ventilation of internal spaces can be continuousfor nighttime cooling. This means designing the building with operable windows tolet hot air escape at night and to capture prevailing night winds.
7. To supplement natural ventilation, fans can be placed at various heights and areasto increase comfort conditions. Fans are effective in generating internal airmovement, improve air distribution and increase air velocities.8. Window openings are advisable at the body level for evaporative human bodycooling. And room width should not exceed five times ceiling height for good airmovement.9. Sunshades and sun protection devices on openings reduce heat gain andglare, and also help in internal day lighting. Louvers that are adjustable can alterthe direction of air flow and lighting.Asian houses have big roof overhangs to protect interior spaces from heat gain andglare. Shading materials should reflect heat, and not be another source of heat.Roof insulation is a must in our warm climate. This reduces the temperaturesignificantly inside the house.
THE BELAROCCA ISLAND RESORTIN THE HEART OF THE PHILIPPINES CASE STUDY. A TROPICAL DESIGN OF AN ARCHITECT SHOWING THE PRINCIPLES OF GIVING INDOOR AIR QUALITY FOR TROPICAL AREAS.
Bellarocca, an island resort off the coast of Elephant Island, has established itselfas one of the country‟s most famous and recognizable resorts, thanks to itsdistinctive architecture, luxurious amenities, and air of exclusivity.The resort‟s name means “beautiful rock,” an allusion to its island location;indeed, the mountainous isle rises dramatically from the sea, and its forest-coveredhills and limestone crags providing a stark contrast against the blue sky and sea, allserving as the backdrop to the resort‟s pristine white Santorini-inspired structures.The resort in the island surrounded by grassy areas was taken advantage and madeas a golf course. Several vegetations such as planting of coconut trees and otherspecies of trees creates a warm feeling at the same time it produces fresh air.
Exclusivity is key to the resort‟s appeal. The island is accessible only toguests, who are ferried in via speedboats or Zodiac inflatable boats.Accommodations are also designed for privacy. Villas are perched onhillsides, open to the sea but screened on all other sides by fences and foliage. TheTerrazas accommodations, located on a cliff above the rest of the island, offerunparalleled privacy. Even the hotel balconies are separated from neighboringrooms by the thick stucco walls and geometric openings characteristic ofMediterranean architecture.Bellarocca‟s architecture and design is another factor that sets the resort apart.Based on the resort‟s principle of organic luxury, the rooms and common areas arewell-appointed, and an effort is made to integrate nature throughout. The villas andstructures are providing huge windows that will let the northeast and southwestmonsoon enter the inside areas.
THE HOUSE IN MAUI, HAWAIISustainable Tropical Building Design Principles Energy and emissions 1. Incorporate passive design measures to maximise the use of natural ventilation, cooling and lighting. 2. Maximise energy efficiency and surpass minimum statutory requirements for energy efficiency. 3. Strive for long-term sustainability and energy security by installing renewable energy generation systems. 4. Maximise opportunities for public and active transport access to the building.
Water and wastewater5. Maximise water efficiency and surpass minimum statutory requirements forwater efficiency.6. Access alternative water sources to reduce consumption of potable water.7. Phase out use of potable water in landscaping.Indoor environment quality8. Incorporate materials and fittings that are not harmful to the health, safety andwell being of building users.9. Use air-handling and temperature control systems that provide a comfortable andhealthy indoor environment.10. Ensure work areas have access to natural light and external views.
Waste and construction materials11. Select materials with the lower embodied energy and environmental impacts.12. Maximise reuse and recycling of construction and demolition waste.13. Allow adequate space for recycling, waste storage and composting by buildingoccupants.Local environment14. Restore habitat and improve community spaces surrounding buildings.15. Minimise the impact during and post development on biodiversity, water andsoil quality, soil erosionand visual amenity.
Passive design„Passive design‟ is design that works with the environment to exclude unwantedheat or cold and take advantage of sun and breezes, therefore avoiding orminimising the need for mechanical heating or cooling.Passive design in the tropics means designing a building to make the most ofnatural light and cooling breezes, and using shading, orientation and appropriatebuilding materials to reduce heat gain and storage.The use of passive design principles in the tropics results in a building that iscomfortable, energy efficient and results in substantial savings in running costs ofboth cooling and lighting.
How we design and construct buildings can affect the natural environment, bothdirectly – by placing buildings and paved surfaces on previously vegetatedareas, and indirectly – through extracting resources to create building materials;emitting greenhouse gases in the manufacturing and transportation of materials tothe site; and through using energy sources such as electricity once the building isoperating.Sustainable building design is about reducing these impacts by designing andconstructing buildings that are appropriate for the climate, have minimalenvironmental impacts, and are healthy and comfortable for building users.Sustainable building design for the tropics differs considerably from sustainablebuilding design for temperate areas. The majority of available information onsustainable design has been produced for temperate climates and is not applicable inthe tropics.
These guidelines have been developed specifically for the wet tropical climate ofthe Cairns region, and provide information on the key sustainable building designelements for the tropics. They can be used in conjunction with Council‟sSustainable Design Checklist to plan the design and construction of sustainablebuildings in tropical climates.
THE HOUSE IN MAUI, HAWAII INTERIORSA HOUSE INSPIRED BY TROPICAL DESIGN AND GREEN ARCHITECTURE
SEVERAL FACTORS TO CONSIDER FOR TROPICAL DESIGN Orientation for minimal solar heat gain: The path of the sun changes gradually throughout the year between summer and winter. Generally the best approach in the tropics is to design so that all walls are shaded from the sun all year round. Depending on the building use, it may be desirable to admit some northern (mid-day) sun in the period May-July, which can be done by planning the width of eaves and awnings . It is also important to remember that in the Cairns region the sun is in the south during summer months and so shading is also needed on the south of buildings.
Orientation to maximise air flow:In Cairns, prevailing winds are south-easterly in the winter months and north tonorth-easterly during the summer months. Stronger breezes typically occuraround April and October.The lack of breeze during the hottest days can pose challenges for achievingeffective natural ventilation, and designing to encourage convection flow is veryeffective at these times.
PASSIVE VENTILATION:Designing a building in a way that maximises natural ventilation will greatlyreduce the need for energy-intensive air conditioning.Air movement over the body, even if the air is not much cooler, creates afeeling of cool due to the evaporation of moisture from the skin.The following methods of passive ventilation are most effective in the tropics.
Maximising breezes:• Orient the building to make the most of prevailing winds.• Align vents, windows and doors to allow air flow through the building – theseshould be aligned in a reasonably straight line for maximum effectiveness.• Minimise internal obstacles or blockages such as internal walls in major flowthrough areas to allow for unimpeded ventilation.• Raise the building off the ground tocatch breezes.
Removing hot air:• Design for convection air flow to remove hot air from the building. Convectionair flow is created by hot air rising and exiting at the highest point, whichnaturally draws in cool air from outside.This natural cycling of air can be created by placing low window openings acrossa space from high window openings. This will be even more effective at coolingif incoming air is being drawn from a shaded area where plants are growing.