Monthly Archives: April 2012
By default, sustainable solutions seek judicious ideas, irrespective of their source, be they traditional or modern, global or local
Many sustainability discussions are increasingly getting into debates outside their technical applications, often leading to digressions and delayed actions. One common area where this phenomenon can be observed is to do with local knowledge systems and traditional technologies. Our ongoing essays on staircase are not an exception – while the novelty of having stainless steel and glass plate stairs is now a possibility in India, why are we shunning them and questioning international ideas? In this new-age global living, why are we glorifying the local “stone age” living, by supporting the idea of stone staircase? Village houses were eco-friendly, but can we return to the regional vernacular style as a solution to urbanising India?
Not just debates
If a reader gets to react as above after looking at the cantilevered stone slab staircase that was featured last week in The Hindu-PropertyPlus , in a way, it is valid! The mandate of Green Sense is not getting into theoretical debates outside implementable ideas; however, it is important to clarify upon such queries, as a process of convincing ourselves. By default, sustainable solutions seek judicious ideas, irrespective of their source, be they from traditional or modern; global or local. Reinforced cement concrete is a high-ended construction option that can withstand sun, rain, fire, heavy loads, breakage or such others, and be secure against any actions of possible burglary. None of these qualities are among the required design criteria for an indoor element! Evidently, RCC stairs are technological and resource overkill. However in the modern times, we cannot avoid RCC on most occasions, especially in high-rise and commercial structures where time is money. Suggesting a vernacular and local option is not to negate the global solution of RCC stairs, but to remind ourselves about regional alternative ideas that could be employed where appropriate.Wider stairs
Traditionally, stone treads were kept thin, often only 2 to 3 inches if its kota stone and around 3 inches if granite, but the width of stair too was restricted to 2′ 6”. Nowadays, we seek wider stairs, say min. 3 ft. wide, hence it’s desirable to cut the granite slabs to min. 4 inches thickness. For stairs that need be wider than 3 ft., stone slabs are an ideal solution, though can be tried upon the expert advice of the stone mason. In case the wall above the steps is not wide or heavy enough to put counterweight, site-specific measures like sand-filled hollow block, staircase beam, built-in concrete layer or such others can be considered. The temporary support of the stone steps can be retained until the super structure is ready, just to ensure the steps are safely put in position.
Despite the foregone discussion, there is one fact: after all is said about green ideas, often it is the prevalent practice that gets built. It’s both a truth and a tragedy.
Among the early materials used for external staircases, stone slabs were the most popular
What is a staircase in its basic and essential form? How did early humans negotiate heights? What are the methods of constructing steps judiciously with least resources and money? What are the maintenance costs of stairs? We are raising these questions not only to define a staircase, but also to be able to design one appropriately and eco-friendly.
Even before people had to climb up to the first floor of a building, they had to climb down to an open well or to a water canal. Walking down the slope of a river bank, carving horizontal levels down to a water tank, digging wells with steps leading to the bottom and such others were among the early explorations in the act of climbing up or down. Climbing up a tree would also have taught the humans to seek a firm and horizontal level beneath the feet. This level, called as tread, and the height to the next tread, called as riser, together form a step. The series of steps is termed as staircase.
Among the early materials used for external staircases, stone slabs were arguably the most popular. A casual trip down to most Indian villages will showcase slabs jetting out of the external wall of the house, going up to the terrace.
With no member in the riser part, this void would let in light, minimise material usage and make the whole assemblage of the steps comparatively easy. Possibly, the inspiration for such stairs might have come from the steps leading down into an open water well, a method with continued application.
Wall and slabs
As the wall is being built, at the pre-marked locations, the stone slab is inserted into the wall, with temporary support at the other projected end. Once the main wall rises, its weight pins down the tread and the temporary end support can be removed.
The thicker the wall, the better for stability. In case the wall is only around 9” thick, the stone slab needs to project out on the other side of the wall at least by 6”, to provide the necessary strength.
If the illustration makes us feel that the tread and risers could be of any size, we are wrong. There are scientific rules that suggest staircase dimensions. The height to which we can lift our feet up and there upon, the forward distance possible is governed by our body measures called anthropometrics and limb movements. Generally, 12” wide tread and 6” high riser has been accepted as the design norm, but this can vary slightly.
In principle, the higher the riser, say 7”, the narrower the tread has to be, say 11” wide. Despite all the talk about standards and measures, humans are uniquely blessed. We can climb up a tree which is like a vertical pole and also climb up a hill which is like the expansive inclined earth!
The present generation may not relate well to the word ‘ladder,’ which has been replaced by ‘staircase,’ yet the idea of moving up has parallel connotations both in buildings and life.
Among the many paraphrases on living that have evolved from design and architecture, the most popular one appears to be about ‘moving up the ladder.’ Needless to elaborate, this line is directly taken from a house with upper floors. Our present generation may not relate well to the word ‘ ladder,’ which today has been replaced by the word ‘staircase,’ yet the idea of moving up has parallel connotations both in buildings and life.
A walk in the antique markets will showcase ladders lying next to old doors and windows, as part of salvaged wooden elements from the past, for modern re-use. Normally with a steep angle, these old timers were having thick wood planks for the steps, also called as treads; thinner ones for the vertical face called as risers; sectional beams as underside support; and sides covered by planks again. They were produced by the carpenters easily and locally, using hard wood for permanent structures and alternatives like soft wood or bamboo for temporary uses. Either way, they were ecologically sustainable, economically cheap and easy to erect, remove, shift and re-use.
RCC to the fore
When steel was discovered, long M.S. sections replaced the wooden beams under the stairs while retaining all other timber members therein. Subsequently, with reinforced concrete gaining popularity, RCC replaced both steel and wood, leading to the now popular ‘all concrete’ staircases. The changing preference for stairs while being in tune with evolving technology has also evolved towards visual grandeur, social image and resource consumption.
It is not wrong to claim, from an eco-friendly, appropriate and judicious criteria, that staircases are among the least of critically analysed building solutions to negotiate heights. Unlike the RCC roof where protection from rain and sun is important, besides the confidence of security, the internal stairs does not face sun, rain or security issues. Hence, it does not always warrant reinforced concrete as the primary material or technology.
Yet, we are building today as if there are no substitutes. The argument is not against RCC as an option, which also has its bag of advantages, but to state that in many cases, non-RCC solutions would have sufficed, with savings on monetary and material resources.
From stone steps
Bamboo, both as a single pole with the thorns left short for steps or built up with two poles with a horizontal member in between, possibly provided the early solutions for the ladders.
Besides the wooden staircases discussed above, we also come across stone slabs used as steps, virtually all over India. The farmer’s house may have a thin granite slab compared to the thick carved stone stairs of a palace.
However, both seem to have been inspired by the stone steps of traditional village open wells, where people had to find a way to reach the bottom of the well.
The stone slabs projected from the wall of the well, going round in an orchestrated manner casting dancing shadows, is a sight to be remembered, and may be applied to houses too!
Where to use and how to build are the deciding factors for success stories in antique materials
In construction, each material dictates its own approach. While all that red oxide flooring asks for is skilled hands; in cement block work, the material quality matters the most; detailing is most important for skylights; and weather protection is an overriding criterion for building with mud. This introduction seemed necessary to respond to the enquiries for the last column on antique pillars, where the right kind of location and application is more important than just being able to procure antique materials. Where to use and how to build with, decide the success stories of old carved wood.
While walls can be built up to any height, antique pillars are short, hence need them in advance to match their heights with the masonry constructions. Though they are mostly found with sloping roofs, they can also be used for flat roofs by adding a brick or stone base to increase the effective height.
Let us never expose these pillars to sun and rain in a new place that they are not accustomed to, for the pillars deteriorate fast. While re-using pillars, the ends developing cracks is a common problem to be carefully attended to. It is better to leave the broken carvings least attended to without much repairing, since the new wood stands out creating a visual mismatch.
Matching the antique with the modern and points of their junction are among the most critical areas of concern. Concrete and wood may need a steel plate in between; a plain stone base may lift the wooden pillar above the floor protecting the base; metal pastes may neatly conceal an awkward joint, also stopping water penetration; clamps and bolts may do a better job than nails; and uninstalling carved four-sided capitals may help if the pillar has to simply meet a flat roof.
In the past all wood applications were made from natural materials, unlike today where chemicals dominate. The former ones would not seal the surface, letting the material breathe and perform differently during varying seasons.
The modern paints, sealants and polishes make wood impervious, in the name of protection, but allow internal dry rot. Hence it is imperative to work with carpenters who use traditional methods, be it linseed oil or hand working to ensure the material lasts. They can also distinguish the type of wood and treat it accordingly.
Re-used carved wood
Building with re-used carved wood demands patience and sensitivity. Once built, they demand time and maintenance. If we intend to use antique materials, it will be good to have not only pillars, but also doors, shelves and such others. Needless to say, the doors have to be bought in advance to ensure perfect fit into the door opening. Without such an overall ambience, antique pillars may look out of place. Mix and match of antique elements with modern construction may appear bad, taking away all sense of history! Let there be the visible touch of tradition.