Kerala's native wooden roofing system with ''Kazhukol'' (rafters) - a brief note

 Typical Kerala wooden architecture  differs from neighboring Dravidian and local styles and can be seen across this state and part of Tulu region. It offers a myriad of innovative and impressive design styles  rich in amazing carvings.  Thanks to the highly talented local craftsmen and their expertise and vast experience. 

Their creative and mind-boggling styles bear testimony to their depth of knowledge in carpentry and knowledge of vastu -thatchu sastras handed down to them from their forefathers. Though  basic principles of architecture are  linked to  Hindu scriptures, the multi-religious social environment of Kerala has given rise to  added grandeur to this genre of wooden architecture with particular reference to ceiling.

Invariably across India the architecture of countless houses, public buildings and places of worship like temples is based on the climatic conditions of the respective regions with tall roof ceilings, ventilation at vantage points, numerous tall windows and in the case of old houses or bungalows wide roofed veranda all around the structure to cut down, glare, radiation and heat in the hot seasons. Many subcultures are surrounded by greenery trees, etc., to keep interiors cool.

Kerala, traditional sloping roof(veranda) in.pinterest.com
Among varying  design styles of  architecture in Kerala state in the SW region  widely adopted is the styley much native to the place and is more  oriented toward environment and geomorphology or terrain of the region. What is called  "vernacular architecture" is quite popular here and it is the art of constructing buildings and shelters which are in tune with  community, climate. and availability of construction raw materials. Indigenous to this region, the architecture deviates  traditional architecture that has been around for centuries 

The characteristic features of Kerala architecture is it uses less masonry work and more wood work because of the availability of quality wood in the forest areas here and many structures include sloping tiled roofing system to drain out water. SW monsoon brings in lots of rain so the buildings have extended roof over the edges to prevent dampness on the wall. 

Madras ceiling with wooden rafters simplicity.in
This brief post covers only Kerala's  wooden ceilings in the houses and buildings supported by wooden pillars, wooden beams and wooden rafters which  in many places carry intricate carvings.  The Kerala roofing system / ceilings  are very much similar to that of time-tested Madras terrace roofing system, in particular, widely followed in Chetty Nadu houses of Karaikudi and other areas of Tamil Nadu.

 The benefits of Madras terrace ceiling  include amazing traditional looks, drastic reduction in heat and radiation from the tall ceiling (11 or 12 ft high} during hot season, durability, easy restoration, effective water proofing, and low embodied energy though it is labor-intensive.

Madras terrace is a time-tested, perfected age-old roofing system  and many colonial buildings have this style of ceiling. Unfortunately, it is among those being forgotten, not because it is defective or inefficient, but only because times are changing and most importantly the thin ceiling tiles are not easily available. The are fixed in the ceiling above the wooden rafters with ground lime  mortar fortified  with jaggery and kadukai (Terminalia Chebula)  which is highly resistant to water, fire-proof and  reduces acidity.; the latter has to be soaked in water for sometime.

The purpose of Kerala roof and celling  is very much similar to Madras terrace but does not include tiled ceiling and lime mortar. Entirely made of quality wood intertwined with wooden beams, cross beams and longitudinal quality rafters supported by wooden pillars, the cladded inner ceiling imparts a unique look and does not allow the heat to percolate downward. It is labor-intensive and needs periodic maintenance to avoid termite attack.

wooden rafters and beams en.wikipedia.org
Above image:  Traditional rafters called Kazhukol and Uttaram. Padmanabapuram palace  near Kanyakumari, Tamil Nadu. It was built around 1600. by the Travancore royal family (photo credit:  (en.wikipedia.org).............

Kerala state, India, justkerala.in
What is unique about Kerala's wooden roof Structural System is it has  three dimensional space frames. The basic structural elements consist of pairs of kazhukol (rafters) resting on an uttaram (wall plate). Pairs of kazhukol will meet on a montayam (ridge) to make the hipped roof.

wood carving on the ceiling Padmanabhapuram Palace wikipedia

Above image: Note the thooku-vilakku (hanging lamp) and the detailed wood carving on the ceiling of Padmanabhapuram Palace.......

In the case of  Kazhukol (rafters) there are many rafters usually supported  by a longitudinal beam and longitudinal stiffener called valabandam that clamp  kazhukol. In the case of a large wide hall  the pair of kazhukol needs a strong longitudinal beam to impart additional strength. The original linear longitudinal beam  is erected and is  elaborated into an arch-like truss. 

pierced rafters (kazhukol) 2.bp.blogspot.com
The space frame work structure is carefully planned and made with  arrays of pierced rafters (kazhukol)  through which lateral poles run and bind the frame. This may cover  small halls with short span. This type of  3-dimensional roof space-truss is reminiscent of the archetype of bamboo constructions and its binding treatments using coconut ropes.  The kazhukol-vala (rafter-rod) construction  design was modelled after the  originally  simple rope-tied construction associated with humble bamboo huts.  Typical sloping roof of Kerala vernacular hut is common in coastal areas of Kerala and Kanyakumari to tackle heavy downpour during rainy seasons

https://www.thehindu.com/life-and-style/homes-and-gardens/a-forgotten-but-perfect-roofing-system/article66094593.ece

https://in.search.yahoo.com/search?fr=mcafee&type=E210IN826G0&p=kerala+style+heritage+ceiling

https://www.heritageartscochin.com/Kerala-style-wooden-ceiling

https://www.simplicity.in/app/articledetail.php?aid=995res are su