The 4 Elements — EARTH, FIRE, WIND AND WATER
A Holistic Approach
Earth — Building materials
The main construction material we use is Concrete reinforced with steel. We will explain in detail why we choose reinforced concrete as the primary material.Utilizing Fabric Energy Storage
To achieve buildings that are more sustainable, we need to consider the whole life of the construction process. While building materials and construction techniques do make an impact on the sustainability of a structure, it is important to put this into context.The environmental impacts from buildings are mainly during their use, as a result of their heating, lighting and cooling needs. Over the whole life of a building only about 10% of environmental impacts are embodied within the building materials.
It is important to keep this critical balance in mind when designing for a more sustainable built environment.
Designing with energy efficiency in mind can reduce in-use energy costs by up to 75%.
The incorporated materials in a building must have reduced CO2 emissions over theirLife Cycle Assesment but even more significant is the ability to reduce the CO2 emissions during buildings life by reducing the need for energy consumption.
By utilizing concretes Fabric Energy Storage through passive cooling and heating techniques we reduce the energy demand in less than 8Kwh/m2 for cooling and heating. In fact we achieve a far smaller digit as the dynamic simulation by TAS shows but this will be discussed in detail at the hair_dryer_project. That is the ability to heat or cool a building only by the energy consumed by an ordinary hair dryer.
Durability
-Concrete is robust, durable, with zero maintenance needs. It is liquid stone. We like concrete.Anti seismic design
-Concrete is suitable for areas with the highest seismic loads.It is in compliance with Greek building code and aseismic design code.Availability.-Minimizing transportation – reducing CO2 emissions
-95% of all structures in Greece are made of load bearing concrete.In Greece as well in Cyprus, almost anywhere we can pour concrete in situ. By reducing transportation of materials we minimize our CO2 footprint and reduce construction cost.
Good value for money
-If well designed and supervised, concrete can give an excellent value for money house. Buildings with concrete increase their value over time.Low tech Know how-high end product
The use of concrete as a building material is widely spread across Greece but not always in the right way. With the implementation of approved sustainable engineering details the results are extraordinary.Fire — Sun
The orientation of the dwelling is of primary importance in order to exploit the advantages of local microclimate. The aim is to use solar radiation (by exposure and shade) and the comfortable ambient temperatures that are available most of the time to minimize the heating and cooling needs. Therefore the building envelope is designed to respond to climatic variations similar to living organisms. The cocoon during summer (April to mid October) period, It opens up and blooms expanding to the outside providing shade and allowing cool breezes to penetrate in the core. Using moveable solar control devices such as sliding louver partitions and fabric curtains a cross ventilation phenomenon occurs reducing significantly the cooling loads. In the winter period the envelope is loosing the protective leaves allowing solar beams to heat the interior space. These are the properties of the sycamore tree.
Winter Period
Sun beams are penetrating deep into the core maximizing solar gains.The high thermal inertia of the interior exposed concrete promotes passive solar gains. The super insulation of the external fabric minimizes heating and cooling losses. Energy requirements for heating purposes are less than 15 Kwh/m2 annual complying with Passivehouse standards.Summer Period
The deep overhang shades the semi hypaethral veranda all day reducing the solar gains by 60%. The moveable external partitions are shading East and West facades for 90% to 95% off the day. North courtyard is ideal for use during hot summer days.
Interior temperatures without any active heating.
The hot air from the buffer zones is redirected to the bedrooms and living room rising the resultant temperature of the rooms.
Fire — Energy
Energy Strategy
The energy strategy we follow is of two stages.Stage 1-Minimum energy kneeds.
First we minimize through advanced design and construction techniques the buildings energy requirements for heating and cooling.Stage 2-Alternative energy strategy.
Then we use alternative energy sources to collect the required amount of energy kneeded for heating, cooling and household purposes. The final energy demand for all the building should be however less than 42Kwh/m2a to comply with Passive house standard.Renewable energy sources
-Solar energy-Geothermal energy
SOLAR thermal panels
All the houses will be fitted with a 14 sq m. solar thermal panels system for converting the solar radiation to energy for domestic hot water purposes. The system, for the area of Greece, is more than enough to cover all domestic uses even at days with minor solar radiation.SOLAR photovoltaic panels
The convertion of sun radiation to electricity through photovoltaic panels is an optional procedure available upon customers request.Geothermal energy
This is a system that uses the thermal energy available from ground to preheat or precool water for heating and radiant cooling purposes respectively. The system is combined with a water to water heat exchanger.WIND
Cooling strategy
Passive cooling is the primary cooling strategy for the dwellings. Natural ventilation is achievd by opening the perimeter windows at the buffer zones and the tilt windows at south and north facades.Cross ventilation occurs.
Night time ventilation.
Night time ventilation is used during summer period from mid April to mid October. By utilizing the Fabric energy storage of the interior exposed concrete we cool the buildings mass during nighttime so that the next day radiant temperature is significantly lower. Inner ambient temperature is kept within the thermal comfort zone most of the summer period. Chart 1.Solar control
during summer the glazed areas of buffer zones are covered by the sliding louvers partitions while glazed elements remain open all day.Cross ventilation excess solar gains to the outsideVery hot days strategy.
The period from mid July to end of August, 35 to 45 days,is characterised by high temperatures during the day and sometimes during night also.Chart 2For that period glazed areas are protected with exterior louver partitions and fubric curtains while windows remain closed to keep the low radiant temperature of the fabric.Inner temperature rises to a maximum of 29.5 C while the exterior is set to 40 C.
Active cooling is necessary for controlling the resultant temperature in the comfort zone only for a few hours during miday.
This is achieved either by geothermal heat exchanger or a solar powered funcoil system and a ceiling fun.
Using moveable solar control devices such as sliding louver partitions and fabric curtains a cross ventilation phenomenon occurs reducing significantly the cooling loads.
cooling strategy — summer period — daytime
Cross ventilation exchaust excess solar gains to the outside allowing cool breezes to penetrate the core. North winds are very common during summer. The roof vent exchaust the hot air from the veranda creating air movement. In windy conditions a downdraught can take place according to pressure conditions on the building.
cooling strategy — summer period — nightime ventilation
At night time the top hung windows are open
Very Hot Days Strategy-chart 2- Passive house no active cooling
When exterior temperature rises to 40C
interior resultant temp is maintained at 28.5C to 30C.
Solar control devices protect all glazed areas and windows remain closed during the day to prevent high temperatures to penetrate the core.Solar control can provide surrounding greenery.
interior resultant temp is maintained at 28.5C to 30C.
Solar control devices protect all glazed areas and windows remain closed during the day to prevent high temperatures to penetrate the core.Solar control can provide surrounding greenery.
WATER
Water Management
Rain water collection and storage. A procedure very common and still in use in many islands of the Aegean.Gray water management
With biological treatment human waste is turned to fertilizer and clean water for gardening.Visualizations are produced by various advanced dynamic simulation software. More deatailed data are available uppon request.
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