Prime Minister Ranil Wickremesinghe last week directed officials to experiment with the building of small double storey houses in areas which are prone to natural disasters like floods. The Prime Minister made this observation at a meeting conducted to assess the progress made in flood affected areas in Galle District. In this backdrop, architect Anuka Wettasinghe has come up with the novel idea to build double storey houses in flood prone areas.
As a result of natural hazards such as floods, earth slips and cyclones people are prone to face such hazards. They group together to rescue the victims from such hazards and find solutions. In spite of the fact that a majority of people forget bad effects of such calamities within a very short period of time, it’s ironic that the attention that should pay to minimize those hazards is at a very low ebb. It’s important for rescuing, preventing and the reduction of the imminent disasters.
It helps to minimize the damage that can be caused to the human lives and properties during a disastrous situation if the buildings are constructed with a proper plan. Due to the negligence and the ignorance of the people and the shortcomings in decision making by the institutions, the concept called ‘hazard resilient buildings , can’t be implemented properly. Therefore, it’s important to focus attention on two building models based on the relief assured for the changing land.
Take precautionary measures to minimize the disasters that may happen in the future by understating the above models.
1. Buildings constructed on flat lands which are subjected to floods and heavy winds-
Suitability and risk situation: When selecting a land for the construction of buildings, it’s necessary to check whether there is approval for constructions and what type of construction can take place. On many occasions, the low lands filled with earth either paddy fields, waterways and drainage systems are sold and construction of buildings takes place. The main reason for floods is the filling of low and waterlogged lands.
It is essential to get the approval of the Low Land Reclamation and Development Board for such constructions. As with lands in the coastal areas, the relevant approval has to be obtained from the Coast Conservation Department. You can obtain information regarding the suitability and limitations regarding the land that is going to be bought by you from the above institutions.
It’s important to follow the following facts after taking a decision to construct a building.
In this regard, you have to inspect the area which is affected by the floods and take a decision regarding the height of the flood. You can decide on the ground floor level to protect it from a flood by doing so.
See model 1.A
The open Ground floor: The building should be constructed on concrete columns, so that the water should flow without a barrier during a flood situation. The damage which may be caused to the columns due to the floating debris will be minimized due to the circular shape of the columns. As mentioned in the 1B model , the ground floor can be used as a parking space and a living area . The model 1A. can be used for construction with a reservation area in the coastal areas which are prone to tsunami disasters.
The high structure/ attic: In the case of an emergency, the wooden structure which is at the lintel level can be used to protect goods from water.
Roof: The roof should be made with a slope more than 25 degrees; more the slope the stronger its ability to withstand winds. Every roofing sheet should be fixed to the’ reepers’ with ‘J’ shaped bolt nuts. Wall plates should be connected with the wires of the beam. Concrete lintel with sufficient gaps( 6x6 ft.) is recommended. In the case of a roof thatched with local tiles, it’s important to put mortar restraining bands. The slope of the above mentioned roof together with the strong anchoring process, prevents the roof from being blown away by heavy winds, specially in the northern, north eastern and eastern provinces.
Let us be informed to get rid of hazards in spite of the fact that we are compelled to live with disasters. Let us get ready by adhering to the instructions.
Garden/ open space: The maximum area for construction is 1/3 of the land. In the balance open space, minimizing the paving of interlocks helps keep the land without being waterlogged. This is managed by covering the land with grass or gravel to absorb water.
Solar panel: A small scale solar panel, which can be carried by hand with 2 bulbs and USB charger, is available for sale in the market. It helps to get rid of inconvenience caused due to interruption of electricity.
2. The buildings constructed on the hilly areas which are vulnerable to landslides.
The extent of disaster: It’s important to find out whether the land where constructions are to take place is situated in an area prone to landslides. The maps indicating potential landslides have been prepared by National Building Research Organization ( N.B.R.O) by studying the vulnerable areas for landslides at the district and Divisional secretary office levels. Anyone can obtain such information from the Disaster Management Units from the above offices. When constructions are made in the hilly areas, it’s necessary to follow the guidelines of the National Building Research Organization in order to obtain the relevant approval. It’s suitable to construct buildings on lands which aren’t categorized as disaster-prone areas by the National Building Research Organization.
The angle of the hill : If the angle of the hill is more than 30 degrees from the earth , it isn’t suitable for the construction of buildings. If the angle is less than that of the earth, it’s suitable for construction. And if it remains between 30 and 5 degrees, construction can be done according to an approved engineering processes.
It’s important to follow the following facts after taking the decision to construct a building.
See model 2
Drainage system : Constructions to be made without blocking the natural waterways. Surface water is sent out through the drains to the natural water ways. This is done using a covering with a concrete layer to minimize the absorption of water. This supports the sending of water out through a drain without sending it over the slope. This also serves as an interception drain which prevents the surface water flowing over the ground.
Building orientation: The length of the building has to be planned parallel to the contour lines.
Foundation: Keeping a substantial length between the foundation and the slope (The instructions of the N.B.R.O have to be followed in this regard)
Not keeping the foundation or other excavations open for a long time which will stop the collecting of water.
Planning the ground floor in the shape of a flat, so that the angle of the ground can be maintained with the least barriers to the foundation of the building. Building of foundation columns by digging deep into the build site adds strength (the foundation has to be laid with the instruction of the engineers)
For the strength of the building structure, deploy a structural plan with structure, concrete columns and beams.
Connecting each of the columns with tie beams at the ground floor level of the building and sill level.
Connecting columns with angular concrete beams over the gabel walls .
Connecting the structure by the door with steel straps and the windows to the wall.
Roof : Fixing the roof with reepers, wall plates and lintels connecting the beam well.
Take precautionary measures to minimize the disasters that may happen in the future by understating the above models. Keep these instructions in mind if you hope to construct a new building, repair or renovatr a building. You can minimize or prevent the damages that may be caused to your life
and properties.
You may think that the cost involved in this method may be high. But when you consider the damage and the calamity caused by disaster, this method may be a better idea. Get advice from professionals and institutions regarding problems that arise in this connection. Specially you can obtain the advice from National Building Research Organization in this regard.
There may be loopholes in the implementation of the existing laws as well as in the conveying of the processes of the models with regard to the general public. Therefore, they have to be corrected by the responsible institutions. However, it’s important to focus our attention on correct procedures because it’s we who have to face disasters.
Let us be informed to get rid of hazards in spite of the fact that we are compelled to live with disasters. Let us get ready by adhering to the instructions.
