Monthly Archives: May 2013

Efficient compound walls

High walls not only cut off the view but also obstruct light and air.

As a society, are we building walls between us? Sociologists may respond positively, analysing how individuality is increasing, gadgets are enabling isolation or neighbours do not know each other.25bgp-green-sen_25_1466947g

Metaphors apart, the physical walls are also increasing their heights between houses, which not only cut off the view but also light and air. The sides of a tall wall are very negative in connotation, not letting sunlight to nourish the plants and making people uncomfortable. If we cannot wish them away, the least we can do today is to keep these walls low, besides seeking alternative modes of doing them.

If we aspire for a green edge with flowering creepers that require least of maintenance and material consumption, then chain-link fence can be a natural choice. We commonly see them demarcating the city corporation gardens, a stretched, open-knitted wire mesh fixed to steel supports at regular distances. Covered with creepers, they can compliment the looks of any buildings, besides bringing fresh breeze into the house. Garden picket fences do an equally good job, but may cost more if done in wood. There have been attempts to do ferro-cement picket fences, which may tend to crack over the years if not cast properly.

Black cudapah slabs are also an excellent option for compounds — space saving with only 2” thickness, easy to fix, recyclable and zero maintenance cost. The unpolished black surface facing the road provides an attractive texture. Granite slab walls with rough cut local stone also make lot of economical and ecological sense. They can be fixed vertically, burying a part into the ground or can slide down horizontally between two edge supports with grooves to slide along. Considering the fact that a plastered surface along the road edge gets dirty very fast, the stone surface stays fresh for years.

With the sense of insecurity increasing, it is common to see cage-like steel grills surrounding the city houses. People with ulterior motives can jump the wall or cut this grill too, so it is wiser to think how much of such grills we need. If fabricated extensively around, they can consume more steel than all the window grills put together! So, let us keep such external grills to the minimum needed or work with alternative security ideas like burglar alarms and such others to save on material consumption.

Individually it may be difficult now to stop doing compound walls, but neighbourhoods, gated communities, new layouts and campuses can start by making studied choices. After all, compound walls are left fully exposed to sun and rain demanding money, time and attention to keep them looking good, hence alternatives like fencing or stone slabs make green sense.

Getting the most out of setbacks

By creative and careful manipulation, the mandatory setback around a house can be made to serve a wide range of functions.

18HAB-greensens_18_1460657eWhen we read about the rate of urbanisation in India, among the many implications discussed, the less focused has been developed land area as a limited earth resource. With the increasing land prices across the years, the site areas are getting smaller for the same budget. Accordingly, if 2400 sq. ft was the standard plot size most people bought five years ago, today it is only a 1,200 sq. ft plot.

Yet we all have the same requirements to fit into this half-sized land. As such, increasing the open areas around the house gets ruled out, but the need to be innovative becomes an imperative.

Utility space

We all need an external utility space, just outside the kitchen or dining area. If this facility is built as a room 5 ft. wide after leaving a setback of 3 ft., effectively we are pushing the house wall 8.75 ft. away from the property edge.

Alternatively, making the setback of 3 ft. wider by 2 ft. gives us a space 5 ft. wide and the house wall is only 5 ft. away from the property edge, saving us 3.75 ft. Much of utility can also happen in the open like a rear yard and in few areas a simple tiled roof can provide the basic rain protection.

Likewise, the car can be parked in an open porch, extending up to the property edge, without a lockable car garage that can happen only after the setback.

The setbacks are mostly left at lower level than the house, after raising the house plinth by a min. 1.5 ft. If they are filled nearly to the level of the public areas of the house and provided there with French or sliding folding doors, surprisingly the internal space of the house appears expanded up to the property edge!

When required the doors can be opened, getting the occasionally much needed extra space during events and get-togethers.

Slope

We also need to consider the setback slope required for rain water drainage. Deeper the plot, longer the setback length for water to flow, requiring higher formation level at the backside.

Smaller the plot, the rear formation levels can be to lesser heights. Incidentally, in case of plots lower than the road, we need not always fill the site setbacks to a level higher than the road.

If rain water percolation and ground water recharge can be properly managed, parts of site can be left at natural levels and money saved.

By creative and careful manipulation, the mandatory setbacks around a house can made to serve a wide range of functions – rainwater harvesting filters and tanks; kitchen gas cylinders; daily dump home composting; small plants; coconut trees; external toilets; open water well; dog kennels; fish tanks and lotus ponds; septic tanks; two-wheeler parking; helper’s room; party spaces; spacious sit-outs; steps down to basements; and; of course; extended gardens.

Legal setbacks are not a setback in land resource utilisation, but an opportunity as well.

Setbacks are good

It was during the early years of town planning that setbacks were introduced to ensure fresh indoor air circulation, accommodate outdoor sanitary connections, and provide room for fire-fighting tasks.

11HAB-greensens_11_1454054eSustainable living demands an ecological approach far beyond mere saving in project money and construction materials; it requires saving every kind of earth resources like water, vegetation or minerals. In an urban context, land is scarce today which we cannot let go waste. In real terms, we cannot really save land, but save unwanted interventions there, hoping to reap some benefits thereupon.

Traditionally compound as a demarcation wall and unused leftover space next to it were not found in Indian settlements, wherein the space between buildings were generally open with people walking around there or provide for allied activities like cattle sheds and rain drainage. It was during the early years of town planning that setbacks were introduced to ensure the space around that would allow fresh indoor air circulation, accommodate outdoor sanitary connections, ensure access to fire fighting tasks and such others.

Nowadays leaving space around a building is a legal requirement in majority of cities. The local authorities and the neighbours can object if an owner leaves less than the officially stipulated width. Considering the benefits of setbacks, we need not question this rule, but unfortunately, this restrictive law does not provide ideas towards making good use of this land. All of the empty setback spaces left around in a city will together count for a large land parcel. Many city master plans do not allow continuous buildings where there are no setbacks at all or even semi-detached ones where two building share a common wall. Both of these development types save lot of side setback spaces.

Where side setbacks are unavoidable, we can at least avoid paving it or concreting it, letting rain water percolate to earth, supporting a few plants. The plinth protection or flagging concrete continues to be a standard specification in projects, which supposedly stops rainwater percolating close to the building foundation, minimizing the possibilities of shrinkage cracks. With the good quality of foundation concretes and the curing time they get, no unequal settlements happen in normal soil and concreting can be saved.

With a desire to build maximum interior space in a given space, many site owners tend to violate the building bye-laws, under the knowledge of the officials, leaving narrow setbacks like two ft. space. Such widths are of no use to anyone — for a person to walk, for a mason to build proper sanitary chambers or for letting in good air and light for neighbouring buildings. If we can keep them as per bye-laws at minimum three ft., not only one can walk but also have some hedge plants.

Alternatively, we can increase this space and with no additional costs of construction, gain many value-added advantages and space for general tasks. The mandatory setbacks, if well utilised, are like free bonuses.

Creative compound walls

The design parameters of compound walls are diametrically opposite to those of the house wall.

04HAB-greensens_04_1447604eSociety has a strange way of classifying activities where construction can be a good case in point. It is a single word but not a single type of activity. Constructing a building is not the same as constructing a road, while suspending a bridge can be a totally different activity. Even within a building the internal wall faces different challenges compared to the external wall, yet we treat both of them as same. We tend to adopt a similar approach to dissimilar contexts, unnecessarily wasting energy and resources. In reality, in every aspect of design and construction, it is possible to think over the options and try to be judicious and sustainable.

Let us look at the case of compound walls, for a while ignoring the fact that this wall is actually not needed. Let us look around and we see most of them being built just like another house wall. Actually, the design parameters of the compound wall are diametrically opposite to those of the house wall.

Free standing

The compound wall is free standing with no weight from the top, hence need not be treated like a load bearing wall. We can design it in any way as we wish. Being short in height and long, the wall may buckle at the sides, so we need to break the linearity by introducing short pillars as vertical members. The top surface will receive rain, which has to be properly closed to stop any water penetration. This can be achieved by tapering the top, fixing a piece of long stone slab, placing cement mortar covering the top surface in a single stretch of coping band or by any other such methods. Rain water hits the ground and splashes backwards to the lower surfaces of the compound wall, necessitating a strategy for easy maintenance.

In the open…

Being exposed to the vagaries of nature – the rain, sun and wind – compound walls tend to crack, shrink and discolour much faster than any other wall. Naturally they tend to appear old and unattractive very fast, requiring corrective measures in advance. The idea of a wall is primarily to demarcate the inside from outside and not necessarily stop people from jumping over. Of course, it may stop stray animals from crossing over, but that is among the minor advantages and does not warrant such a heavy expenditure.

Let us keep the compound wall to the minimum height required; provide it with openings to avoid the solid negative appearance; design it suggestively as the frontal frame of the house; match it with the building by material, colour or design style; make it simple yet elegant looking. In many ways, these walls are a design opportunity towards constructing a creative wall and an artistic edifice in front of a meaningful building.