Heating

For uniform heating of the room air, convector heaters can be replaced by a floor heating system. Problems arise only where large window areas are involved, but this can be overcome by the installation of additional heating-such as floor convectors.

In general, surface heating includes large areas of surface surrounding a room and involves relatively low temperatures. Types of surface heating include floor heating, ceiling heating and wall heating. With floor heating, the heat from the floor surface is not only imparted to the room air, but also to the walls and ceiling. Heat transfer to the air occurs by convection, i.e. by air movement over the floor surface. The heat given to the walls and ceiling takes place due to radiation. The heat output can vary between 70 and 110W/m^2, depending on the floor finish and system employed. Almost any usual type of floor finish can be used – ceramics, wood or textiles. However, the diathermic resistance should not exceed 0.15m^2k/W.

House dust allergies can be a problem in heated rooms. Previously, precautions against house dust or dust mite allergy paid no attention to the effects of heating units. Heaters cause swirling of house dust containing allergens, which can then rapidly come into contact with the mucous membranes. In addition to this, there are insoluble difficulties in cleaning heaters which have convection fins. It is therefore advantageous if heaters are designed to embody the smallest possible number of convection elements and to have straightforward cleaning procedures. These requirements are fulfilled by single-layer panes without convection fins and by radiators of unit construction.

**Storage of heating oil** : The quantity of heating oil stores should be sufficient for a minimum of 3 months and a maximum of one heating period. A rough estimate of the annual requirement for heating fuel is 6-10/m^3 of room volume to be heated. A maximum volume of 5m^3 may be stores in a boiler house. The container must b within a storage tank capable of accepting the total quantity. Storage containers in the ground must be protected from leakage, e.g. through the use of double-walled tans, or plastic inner shells. Maximum capacities and additional safety measures are prescribed for areas where water protection regulations are in force. Within buildings, either plastic battery tanks with a capacity per tank of 500-2000 litres may be installed, or steel tans which are welded together in situ, whose capacities may be freely chose. The tank room must be accessible.

The tanks must be inspected for oil-tightness are regular intervals. In the event of an emergency, the tank room must be able to retain the full amount of oil. Tank facilities must have filling and ventilation pipe lines. Additionally, overfilling prevention must be incorporated and depending on the type of storage, a leak warning system may be prescribed (e.g. in the case of underground tanks).

The floor screed for floor heating systems must satisfy local regulations. The thickness of the screed depends on the type of covering used, its preparation and the anticipated loading. A minimum covering over the heating pipes of 45mm is prescribed when using cement floor screed and heating pipes which are directly above the thermal insulation. If there is no fininish over the basic floor, then a minimum total depth of 75mm is required. The floor screed expands during use, and a temperature difference arises between the top and bottom surfaces of the screed.

Due to the differential expansion, tensile stresses occur in the upper region of the layer. In the case of ceramic floor coverings, this can only be countered by top reinforcement. On carpeted floors or parquet floors the reinforcement can be avoided, since the temperature drop between the upper and lower surfaces of the floor covering is less than in the case of a ceramic finish. Special requirements are contained in the thermal insulation regulations with respect to the limitation of heat transfer from surface heating, irrespective of the choice of type of insulation method: In surface heating, the heat transfer coefficient of the component layer between the hot surface and the external air, the ground, or building section having an essentially lower internal temperature, must not exceed a value of 0.45W/m^2.

The maximum permissible floor surface temperature for a permanently occupied area is 29^c. For the boundary zone it is 35^c, where the boundary zone is not to be wider than 1m. For bathrooms, the maximum permissible floor temperature is 9^c above normal room temperature.

Under normal conditions, floor heating is possible, since the heating requirement seldom lies above 90W/m^2. In only a few exceptions (e.g. when there are large window areas, or when the room has more than two external walls) is there a greater heating requirement, and then additional static heating surfaces or air heating must be installed in additions to the floor heating.

SOLAR ARCHITECTURE-1

Organization of the ground plan

In the passive utilisation of solar energy, the heat is utilised through direct incident radiation and heat storage in specific structural components such as walls and floors.

Because of the condition under which solar energy is used passively, the arrangement of the ground plan necessarily follows a particular logical layout. The continuously used living and sleeping accommodation should be south-facing and provided with large window areas. It is useful to provide glazed structures in living and sleeping areas. It is useful to provide glazed structures in these living and sleeping areas. There are three important reasons for this :

(1) Extension of the living area

(2) Gain in solar energy

(3) Provision of a thermal buffer zone

The little-used low-temperature unheated rooms, with low natural light requirements should be north-facing. They act as a bugger zone between the warm living area and the cold outside climate.

Use of solar energy

In the use of solar energy, a distinction is drawn between the active and passive use of solar energy.

The active use of solar energy necessitates the application of equipment such as solar collectors, pipework, collector vessels circulation pumps for the transfer of the solar energy. This system entails large investment and maintenance costs which must be recovered solely by saving in the cost of energy. As a result, such systems cannot be operated economically in single family houses.

The passive use of solar energy necessitates the use of specific structural components as heat stores, such as walls, ceilings and glazed units. The efficiency of this system depends on specific factors :

(1) Climatic conditions – mean monthly temperature, solar geometry and incident soar radiation, hours of sunshine and level of incident energy radiation.

(2)Methods of using the solar energy-indirect usage, direct usage.

(3)Choice of materials – absorption capability of the surface and heat storage capability of the materials.solar houseSolar energy.jpg

LOFT WINDOWS-1

In planing the size of window, the optimum daylight level relative to the purpose of room must be the deciding factor. For instance, building regulations require a minimum window area of 1/8 of the floor surface area for living rooms.

Large windows make living rooms more comfortable. The window width in secondary rooms can be chosen according to the distance between the rafter. Generously wide windows in living rooms can be achieved by the inclusion of rafter trimmers. Steeper roofs need shorter windows, while flatter roofs require longer windows. Roof window can be joined using purpose – made prefabricated flashing, and can be arranged in rows or in combinations next to or above one another.

 

Global History of Architecture

FIRST SOCIETIES
Though modern humans developed around a millions years ago, the first tangible evidence of we might call human society began to develop around 200,000 years ago.
KEY PLACES
• Blombos Cave, South Africa (140,000-75,000 BP)
• Rhino Cave, Botswana (70,000 BP)
• Kalahari Desert, Botswana

KEY DATES
• 140,000 – 100,000 BP Human Society Developed (South Africa)
• 90,000 BP (ca.) Humans leave Africa
• 80,000 BP (ca.) Humans in Indonesia
• 74,000 BP (ca.) Mt. Toba Eruption
• 45,000 BP (ca.) Humans reach Australia
• 45,000 BP (ca.) Humans reach Europe

Rock art
Sometimes called petroglyphs (from petro, meaning “rock,” and glyph, meaning “symbol”)—can be found from the Arctic Circle to the tip of South America, from southwestern France and the deserts of Africa to the Himalayas and China all the way to the deep canyons of the southwestern United States and the cliffs of Bolivia. If one counted them, they would be in the many thousands, perhaps even millions.
These drawings give us a vivid impression of an active and dynamic world, suggesting the presence of seasonal and ceremonial coherencies. But we should not see this art as an attempt to represent real-life events. Rock art representations are not in that sense like modern photographs. An image of men shooting arrows may not be a hunting scene, but a demonstration of a person’s fighting spirit. Animals may be the spirit of those who have embodied the form of an animal to take on its potency. Early rock art could also have been an attempt to bring the ancestors who embody animal spirits into visual range and associate them with particular places in the natural landscape, for it is not just the representations that one has to consider but their location as well. Many of the sites are associated with water, and almost all seem even today to evoke something special in the landscape, whether an unusual geological formation, a special orientation to the sun, or a feeling that one can get of being in an alien or subterranean zone.

!Kung (global First Societies, some of which still exist today, such as the !Kung (San) in Botswana.)
The !Kung word for hut is chu/o which means literally “the face of the huts,” thus emphasizing the orientation of the hut toward the central, communal space. Immediately behind the zone of the huts is where ash from the fire is heaped along with spent nutshells. Behind that is a ring where the fire pits are made and butchery of animals is undertaken.
This is surrounded by an empty area and beyond that, about 200 or so meters away, the zone for defection. Past that there is the t’si, which means bush or wilderness. The !Kung do not deify or particularly revere the semiarid savanna that surrounds them or attribute supernatural powers to it.
The dry season villages can contain up to fifteen huts accommodating about fifty people. When the settlement is founded, a central fire is lit by the senior man and is kept lit at all times. If it were to go out, only the headman can relight it. It is from this fire that the other fires are lit.
The huts are placed in a ring around the central area with each hut having a fire place in front of it, which is where the food is cooked and people socialize. Each hut, with its own hearth, is a marker signifying the residence of one nuclear family. Typically huts are close enough so that people sitting at different hearths can hand items back and forth without getting up.
The most senior households will position themselves on the side closest to where their ancestors are said to have come, with married children’s huts strung out to the right and left. Other households make up the rest of the circle. The huts have no sacred zones inside or outside the house. People, in fact, do not live in the huts. Instead they will sleep around the fire. The huts are mainly used to store hunting gear, personal items, and for an occasional nap. Despite this, the huts are an important symbolic purpose identifying the locus of a family in the group.
(A Global History of Architecture – MITx)

ACCESS FOR FIREFIGHTERS – 1

Provision should be made in design to allow firefighters good access to the building in the event of a fire, and to provide facilities to assist them in protecting life and property.
Sufficient access to the site for vehicles must be provided to allow fire appliances are ladders, hydraulic platforms and pumping appliances. Access roads for fire appliances should be at least 3.7m for pumps and 4.0m for high-reach appliances is required. The respective turning circles of these appliances are 17m and 26m between curbs. Allow 5.5m wide hardstanding adjacent to the building, as level as possible (Not more than 1:12) with a clearance zone of 2.2m to allow for the swing of the hydraulic platform.
Firefighters must be able to gain access to the building. The normal escape routes are sufficient in small and low buildings, but in high buildings and those with deep basements additional facilities such as firefighting lifts, stairs and lobbies, contained withing protected shafts, will be required.
Fire mains in multi storey buildings must be provided. These may be wet or dry risers (fallers in basements).
A means of venting basements to disperse heat and smoke must be provided. In basements, flames, gases and smoke tend to escape via stairways, making it difficult for firefighters to gain access to the fire. Smoke vents (or outlets) are needed to provide an alternative escape route for these emissions directly to the outside air and allow the ingress of cooler air. Regulations stipulate the positions and sizes of vents. Either natural venting or mechanical venting in association with a sprinkler system may be used.