This article is primarily regarding the transplantation of the Kerala houses seen in Dakshinachitra, Chennai. Most of the Kerala buildings have a lot of timber members, including the walls. But the principles specified below are applicable to other kinds of buildings also.
List of Contents:
1. Measured Drawings of Buildings
It should be assumed that all the members will have to be numbered and reassembled at the site. All the numbers should be noted in a drawing or numbered such that one can easily find out which piece goes where. The following points should be borne in mind while making the measured drawings:
Cross-check all the measurements at the site itself. Unlike a measured drawing for documentation purposes, you will not be able to cross-check once the building has been dismantled.
Calibrate your measuring tape with another tape. There could be differences between your measuring tape and the tape you are using at the site for reconstruction.
Enough photographs should be taken before demolition and during various stages of the demolition of the buildings to leave little doubt regarding what goes where.
No measurement or details should be left out with the thought that one has photographed it. An approximation is always an approximation and not accurate.
For details such as cornices, make a template before demolition and use it for reconstruction. If you are measuring any detail, please specify in the drawing which cornice you are measuring, where that cornice is located, etc.
The levels of the various rooms of an old building may be very confusing, and thus, they should be clearly marked in the drawings.
When measuring the heights of the walls, parapets etc., it should be noted that the floors of the building will not be absolutely level as old craftsmen were not bothered about the rectangle shape and levelling of the rooms.
When the timber roofs are measured, the distance between the masonry walls is not critical. What is more important is the distance between the wall plates.
You should study the basic techniques of construction. Otherwise, it will be difficult to find where the mistakes happened. For example, we dismantled the door of one of the houses to its individual pieces (10 to 12 pieces). Since no nails were used, it was easy for us to do. Finally, we assembled them back into a door at the site. Each timber member of the door was numbered and recorded in the drawing.
2. Method of Numbering the Components
The numbering of the different pieces of the building should be done before the demolition starts. We have to give numbers to the different pieces of timber and mark the same on the drawing. For example, we may mark the number on a rafter as FRN8. This means that the member belongs to the first floor (F), R denotes that the member is a rafter, N denotes that it is present on the Northside and 8 denotes the number.
So looking at the number, we know that the particular piece comes in which floor, for which it is used, and on which side it comes. For a floor beam, we might give the number as GSC4, which means that the member is on the ground floor, it is a secondary beam, it comes in Room C and it is the fourth one. In the case of the wall plates and beams, the north or east direction will have to be marked to locate the correct position of the timber member in the reconstructed one.
3. Demolition of the Buildings
A lot of measurements are taken while we do the demolition of buildings. Also, the numbering on the pieces which had been inaccessible will be done during the demolition process. Another problem that might crop is that what you see as a single member might be two or three different members when it is dismantled. If one is aware of all the details of the construction of that building, then the job is fairly simple. The method of structure relocation we adopted in Dakshinachitra is that the head mason, head carpenter, the site engineer and the architect will be at the demolition site supervising every stage of the demolition.
Loads of damaged and worn out pieces will be there in an old building. In Dakshinachitra, the Kerala houses we transplanted are those in any way going to be demolished. The main reason for the owner to demolish the building is that he/she is not able to maintain the historic building because a considerable amount of money will have to be spent since repairs were not done on time. Some damaged pieces, especially timber members, will break into two or three and may not be used in the reconstruction. You will have given a number to this particular beam, for example, GMD2, which is the main beam in Room D on the Ground Floor.
The fact that GMD2 has been damaged beyond usage should be recorded in the drawing and a logbook; otherwise, you will spend hours looking for this member. During the demolition of the buildings, the critical dimensions were marked on a long timber piece (for long measurements, timber pieces will have to be joined). This scale was used at the job site for setting out the building, because it will avoid any tape measuring errors, and the craftsmen were more comfortable with this approach of scaling the critical measurements.
4. Procedure Adopted for Structure Relocation
The procedure adopted in the structure relocation of the Dakshinachitra houses is that the building materials which had been demolished were brought to the reconstruction site. The first step was to stack the materials in the order in which it was required for reconstruction. The foundation of the building may start while the cleaning of the materials and the repair of the damaged pieces takes place. The number marked before demolition will be on a side that is clearly seen outside. One of the main objectives in cleaning the timber members was to transfer the number to another side that will not be seen.
This should be checked by two people at least because any error in the numbering at this stage will cause several problems and will be laborious to find out. The cleaning of the timber was carried out to remove the dirt, any paint or similar coating applied over the years. The cleaning was mainly done by sanding. No chemicals were used. The paint coatings were removed by using a burner and then scraping it. If the timber had been affected by any termites, we ensured that the insecticide was applied to the particular timber member alone. It would have been expensive to treat all the timber members with the preservative.
Thus, it was decided to treat the affected members alone and see when the problem arises. No timber preservative or protective coating was applied to the rest of the timber members. No paint or protective coating was applied over the cleaned members. They were cleaned, and a sealer coat was applied. We may employ treatment procedures if the timber is attacked in the future since no protective covering, such as a film, was applied to. Each rafter, beam etc., will have to go in its proper place. There was no adjustment in reconstruction even though the rafters, beams etc., could be interchanged.
There was no attempt to correct any mistake in the old buildings. Such errors can be seen in the newly reconstructed buildings. The policy adopted was to replace the old timber only when necessary from a structural point of view. In many cases, one can find a lot of termite eaten pieces, which had been stabilized because they continued to serve the purpose they were intended to. We used old timber from other demolished structures to fix the reconstructed building whenever we needed to replace irreparable old timber. In the case of some large timber beams where the prices were prohibitive, we had inserted steel sections to carry the load to strengthen the beams. But none of these was visible externally anywhere in the buildings.
5. Craftsmanship
When compared to the skill necessary to construct a building, relocating one does not necessitate the use of highly skilled craftsmen. But while we were involved in the reconstruction, there were many problem areas where we did need high skilled craftsmanship. The problems were handled the same way they would have been solved by a traditional craftsman. While we were doing the reconstruction, the comparatively young team of craftsmen working with us had said a few times – “My father knows about this. I will have to ask him.” In many other cases, we consulted the old craftsmen on various topics required for the reconstruction.
6. Documenting the Sloping Roof
For calculating the roof slope and to find the missing timber members, we used the traditional system as used by the traditional craftsmen. They used a different scale for measuring the roof and the buildings. The scale is known as “Kole”, which is approximately 72 centimetres. The dimensions of beams and the length of the rafters etc. were calculated using this scale. The same measurement system was used for the roof and other timber members.
As there were no standard measurements in the past, when the 'Kole' was used to measure roofs of buildings, it varied from building to building and location to location. One Kole is equivalent to 24 angulas, and it varies from 71 to 75 centimetres from one place to another. The importance of the Kole measurement is to know the slope of the roof. The craftsmen did not do the sloping roof according to any degree slope or rise: span ratio. They had a different system of calculating the slope of the roof, which is the reduction from a 450-degree angle.
When a carpenter says the slope of the roof is 1:6, it signifies that the height is reduced by 1/6th, compared to a 45-degree slope. For this, we had to know the exact length of the ‘Kole’ which they had used in the old building. For instance, in the Calicut house, we could locate the Kole which was put under the wall plate. In the other Kerala houses, the traditional craftsmen marked the measurements they used to construct the roof somewhere with the chisel.
7. Economics of Transplantation of Buildings
During the structure relocation, we discovered that the cost of restored structures with all of this timber and other materials was roughly similar to the cost of a new building. This is because we got the old buildings at a much lesser price (Roughly 25% of the cost of a new house at that time). These buildings were already on the market and were expected for demolition. The people who buy these old buildings are demolition contractors who sell the old timber to those who make cheap doors, windows, almirahs & furniture for the poor people.
8. Conclusion
One reason for getting these old buildings which are already on the market for demolition is that it is not against conservation. By transplanting these buildings, the visitors to Dakshinachitra could see these old buildings in a single campus even though they had been separated from their traditional surroundings. But the skills required to relocate a structure have definitely come down over the years, but the craft is still not dead. If we are able to do new buildings using traditional building materials and techniques, it will thrive once again.
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