Category Archives: BACKGROUND

Straw — Bale House — Hasandede

The first straw-bale building in Turkey was begun in mid summer 2000 when Harald Wedig led a Workshop in Hasandede 90 km southeast of Ankara. Nine architectural students from Gazi University, two architects and three volunteers participated. Demet Irkli Eryildiz designed the project. The Hasandede Municipality supplied the land at the prominent site, and the Research Fund of Gazi University and Kirikkale branch of Chamber of Architects provided most of the building materials while the State Farm in Bala provided the straw — bales. The Global Ecovillage Network (GEN) — Europe paid for Harald Wedig’s training and travel costs.

The workshop aimed at building an earthquake-resistant and ecologically sound rural dwelling. As it well known, straw-bales have very high insulation value for winter and summer conditions. The wooden post — and — beam structure was chosen for earthquake considerations. The concrete slab, which is 10cm thick, was poured on top of the masonry foundation. Diagonal crossties of heavy wire were attached from the foundation to the upper frame of the roof structure.

A wooden trussed — roof system and light metal coverings were chosen for their earthquake resistance, durability and ability to harvest clean rainwater. Both foundation and roof were properly insulated against cold, humidity and vapor. Inner and outer surfaces of the straw-bale walls were plastered with local earth. The window and door
openings were designed mostly on the southern side to achieve more solar gain and wooden frames were chosen as natural building elements. The building will be offered to Hasandede Municipality as an ecological training center.

Outlook

The renovated terrace house has been accepted very well by the residents and the architectural media. It offers tangible and visible proof that new technology today can lead to highly effective and long-lasting success. We already are working on several further related projects and predict a great future for vacuum technology in professional architectural renovation of the existing building stock — also with regard to social and cultural aspects.

New living space

SHAPE * MERGEFORMAT

vor umbau

before renovation/ improvement

Primary energy for heating

Lichtblau Architects, January 2004

Predicted heating energy demand for Germany. Source: IWU, Darmstadt

Use of Solar Volume in Design of Site Layout

Ziva Kristl*, Dr., Asist. Prof., Ales Krainer* Dr. Prof., University of Ljubljana, Faculty of Civil and Geodetic Engineering, Chair for Buildings and Constructional Complexes, Jamova cesta 2, 1000 Ljubljana, P. O.BOX3422, Slovenia, tel: +386 1 4768 609 fax: +386 1 4250 688 e-mail: zkristl@faa. uni-li. si *ISES member

Introduction Thermal and luminous evaluation of a site layout with the help of the quantity of solar radiation as well as the density of urban development should present important starting points for a developer or a planning official. The investigation of architectural concept and its influence on thermal and luminous conditions in a building and its surroundings are essential in the early stages of design. During this time it is still possible to change site layout, building orientation, its form and dimensions. By doing so an energy conscious design with relevant functional zones can be obtained.

When designing a solar layout (or a solar urban quarter) the aim is to make a plan that will assure solar exposure of building facades during certain periods of time [1,2], especially during the cold part of the year when solar heating is desired. On the other hand the solar rights regulations, considering the minimum solar exposures during the year, have to be respected. A design that does not respect the solar rights of each building may cause unacceptable conditions in the building and can be refused by the authorities.

Today exist a number of ways for checking and evaluating of site layouts [5,6,7,8] regarding solar access and solar rights. In this paper we investigated the relevance and accuracy of solar volume method for urban planning and estimating of solar access [9]. This method enables the designer to obtain maximum volume of the building, which will not cast shadows over the chosen limits. The volume in designed with regard to solar incidence angle or solar exposure duration and can be optional (for a town, a neighbourhood or a building). Also we tried to establish if the method could be used in Slovenian solar rights regulations. During the investigation we wanted to answer the next questions:

• Is it possible to obtain long solar exposure of the facades and still keep normal/high urban density?

• What incidence angle is actually acceptable (in the literature 10°-15° elevation angle is recommended)?

• Shall we consider all the buildings equally, regardless of location?

• Is east and west solar exposure checking necessary, bearing in mind summer overheating?

For this reason we checked the method on two levels: on the level of solar rights (on 3 reference days) and on the level of prolonged solar access. We established critical periods in which the solar incidence on the buildings is desired, from which the reference solar incidence angles were determined. The results were compared with the results of the two established methods: sun-on-ground method and the iso­shadow method (Fig. 4,5) [3,12]. We compared accuracy of the methods and analysed differences and level of approach. The first two methods were calculated with the computer programme "SENCE" (Shadows) which was developed at the University of Ljubljana, Faculty of Civil Engineering [4]. The third method was assessed with a newly developed computer tool.

A Prismatic Solar Hybrid Collector

The PSHC panels in our daylighting system are thin, planer, sawtooth made of clear acrylic material, and consists of an array of acrylic prisms with one surface of each prism forming a plane surface as the prism backing, ша 42cJeBIBe

There are two refracting angles, 42° and 5° ‘ ‘

(Fig.1). For deep penetration of sunlight, these prismatic panels accommodate a wide range of _

solar altitudes. The occurrence of refraction due Fig-1- A prism geometry for PSHC
to these panels is used to change the direction of transmitted light rays (Daylight in Buildings, Program Annex 29, July 2000). In winter, direct solar radiation penetrates the system at a high degree, which creates a temperature difference after passing through the glazing area. This effect produces good thermal conditions inside the room or a building.

A typical PSHC unit installation has more than one-prismatic glazing module consisting of thin planer sawtooth transparent sections made of acrylic material. For this experimental work, these panels are obtained from “SITECO” Beleuchtungstechnik, (Germany) with prismatic elements integrated inside the intermediate space. Unit dimensions are 1190mmx790mm. The details of construction of the panels are, (1) external sheet: clear glass, approx-5mm, (2) internal sheet: laminated safety glass, approx-6mm, (3) intermediate space: width approx-34mm, with two prismatic elements and (4) total thickness: approx-45.5mm. The prismatic elements are composed of square surfaces of approx 205mmx205mm.

Table.1. Coefficients of transmission and reflection (Daylight systems pp.1-5 SITECO).

Glazing

type

Transmission

coefficient

Reflection

coefficient

Prismatic

element

42o/5o

0.76

0.18

These panels have a total solar energy transmission coefficient, which is composed of the coefficients of direct solar transmission and of secondary heat transfer. The direct solar transmission coefficient specifies that part of solar radiation incident on the glazing surface that is directly transmitted inside. The secondary heat transfer coefficient signifies the part of incident solar radiation, which is transferred inside by convection and longwave IR-radiation through the individual glass sheets and prisms, which produces heat inside the room (Table1).

Fig.2a. Concept of PSHC.

The panels are fixed on a small window (the dimensions of window were 2m long and 0.6m wide) of the south facing wall of the target room. The target room building is of rectangular style with dimensions of 2.4m high, 2m wide and 3.9m long. The target room has been developed by keeping in view the concepts of reflecting sunlight to the ceiling, to improve the visual comfort by increasing ceiling luminance levels across the depth of the room, and to produce uniforms glare-free illuminance and better thermal conditions across the room (Fig2.a). A small fan is fixed just below the entrance of target room in the south­facing wall in order to circulate the warm air inside the room during winter. The whole daylighting system is designed for latitude 36.5o (Dejeon, Korea). The design of the target and reference rooms is shown in Fig.2b.

Fig.2b. PSHC twin test cells in KIER.

“Econovation”: Ecological Renovation of aSocial Housing Unit

Ecological renovation of the building stock is one of the important problems together with construction of ecological new sites. In this part of the world, which has stabilized population, it should even be more emphasized than the new constructions. It is impossible to separate energy related elements from architectural elements. Spatial organization and architectural form are firmly interconnected with such factors as solar control, ventilation, insulation, location of (thermal) walls, surface properties and color. For ecological renovation these considerations are reference points;

I — The aim of the study is to show exemplary renovation of a social housing unit to be an ecological house in Batikent-Turkey. A financial model will support implication and comparative analysis on energy, water, and urban agriculture.

II — Batikent’ site is the biggest (third in the world) housing project implied in Turkey. Between 1981-1990, 50.000 houses were built in Batikent. Aspects ofecological design principles are applied in some district implications. But holistic approaches were not managed. After 18 years of living in the area, buildings needed renovation. “Ozgur Cooperative" is one of the most interesting district settlement projects in the area. It consists of 306 triplex units. Highlights of passive solar energy design and vernacular architecture approaches used in design.

III — Architect of the project in Batikent, with an expert team, plans to revise his own house as an experimental transformation to Eco-house. Objectives of the study are;

The Eco renovated house is an ecologically renovated dwelling that is 150 m2 and has two stories and a basement. Cubic dimensions of the building optimize heat load. Entrance, living, dining, kitchen and 2 bedrooms are located to access of Southeast wind. With addition of 2 greenhouses a tampon area in summer conditions created, to collect heat when needed. Greenhouse is at the centre of building. Its design eases to conduct desired air to other spaces via direct opening plus special details for conduction. That is living and bedrooms adjacent to greenhouse heat is collected and stored adjacently to the thermally linked spaces. Day to night closing and opening of shutters for windows, greenhouse is used to provide appropriate thermal comfort conditions.

Technical Aspects

■ To revise water system to separate grey water from sewage and collect rainwater.

■ On balconies and the garden there has been edible landscape and it will be revised.

■ Greenhouse will be constructed to connect inner spaces as a heat transferor.

■ Convert materials, finishing and appliances to be healthy, safe and economical ones.

■ Re examines insulation ofwalls, windows. Shutters will also be insulated.

■ Install heat collectors for heating, cooling and domestic heat water systems.

■ Earth pipes will be installed to supplement this above-mentioned system.

■ PV’s will be installed to supply electricity for domestic consumption.

Wind speed and the direction are appropriate to overcome the overheating problems during hot seasons while the solar energy is more than enough to supply the very small amount of space heating requirement during winter using direct gain windows. Ordinary flat plate photo thermal converter needs can easily supply domestic hot water.

The system sizing for the stand-alone PV installation is done by the procedure outlined in the book written by Green. The load is as follows: Solar radiation value for Ankara is 4 MJ/m2 — day; Total daily requirement of electricity is obtained to be around 2175 Wh/day.

The number of modules is calculated as 24. The inclination angle of modules is calculated to be min 15 Degrees. (Latitude 15 Degrees). The reserve capacity of the batteries is assumed to be 10 days, which is quite reasonable for sunny and arid regions. This calculation gives 18 batteries. Efficiency of lead-acid batteries is 80% nickel-cadmium batteries 70%. The cost for the solar panels; The modules $ 7200+Bateries $ 4000+Maintenance $ 2000=Total $ 13200. South and/or east facing direct gain windows can easily supply heating requirements during winter months.

Greenhouses attached to both south and north facades. Heating by thermal mass and cooling, edible landscape, creation of additional space and recreation are the aims of additional structures. Greenhouse shutters will be added for both summer-winter; day — night insulation. Green house will completely moved and become a garden in summer.

Insulation: Existing 2 cm insulation material is adjusted to be 5cm and sandwich brick wall. Roof insulated with 8cm Styrofoam. Existing single glazing is improved to be double, using the old wooden frame. Shutters repaired and inner faces are insulated by film. Existing thermal mass for some of the rooms might be effective in solving insignificant requirements of cool nights and hot afternoons.

Main structure was made out of concrete, the materials for renovation have been selected with aspect to renewable resources and re-used materials are mainly brick, wood and natural insulation materials such as prelate. Structures and attachments will be made with screws or studs, not nails, so that may be easily demented and parts used elsewhere. Lime mortar has been used to make it easy to take down the wall and to clean the bricks. First floor, windows and roof are made out of wood. All parts of the external walls and the roof are accessible for replacement of materials has aged.

Toilet solid wastes, kitchen and garden organic wastes, leaves roots are collected, stored and composed to be fertilizer in the edible landscape in and outside house. Grey water was connected to city sewers, after ecorenovation Bath and WC grey waters are collected in basement to be naturally purified and used in garden. Garden and greenhouse vegetation and trees are planted for household requirements: Edible landscape design according to their light, water irrigation requirements plus aesthetic and creative demands of the people living in the house. Evergreen trees obstruct prevailing wind direction. On south fruit trees planted.

Daylighting design by means of a scanning sky simulator: applications to different typologies of daylighting systems

C. Aghemo, A. Pellegrino, V. R.M. Lo Verso

Politecnico di Torino, Dipartimento di Energetica, Faculty ofArchitecture chiara. aghemo@polito. it

Introduction

The use of daylight in non-residential buildings has become an important strategy to improve environmental quality and energy efficiency by minimising artificial lighting consumption, heating and cooling loads. Daylighting design and building design should be inseparably linked to each other, in one only creative process aimed at generating appropriate architectural and technical solutions while reducing building energy consumption1. Nevertheless, daylighting strategies are seldom considered in the earliest stages of a building design: this is often due to the lack of simple tools able to accurately predict the performances of daylighting systems exposed to lighting conditions varying continuously in distribution and intensity, according to seasons, day’s hours and specific climate conditions.

As an alternative to a software based-on approach2,3, an efficient prediction tool for daylighting design is represented by the use of scale models under an artificial sky and sun, purposely designed facilities which enable reproducing daylighting conditions by means of artificial lamps and luminaires.

Scale models are often used by designers to analyse design solutions in a three­dimensional physical representations, hence belonging to design culture and assuring a good adherence with real situations, since even complex spaces can be reproduced; furthermore, the simulation ofopaque and transparent materials’ optical properties is easier in most conditions, thanks to the possibility of using real materials.

Using scale models under an artificial sky and sun makes it possible to simulate the dynamic behaviour of daylight to allow the comparison of the environmental performances of different daylighting systems: it is actually possible to maintain constancy and repeatability of luminance distribution of the sky vault and the apparent movement of the sun, assessing a daylighting system with reference to same daylighting conditions4,5,6.