Earthen pots Insulation System: Thermal Comfort Design Competition for Taru, June 2014
Heat conduction through a materials can be lowered in several ways by using insulating materials such as paints, tiles, or by increasing thickness using air cavities etc. We used a simple principle of air cavities through earthen pots on the roof surface, to achieve thermal comfort. In principle, use of cavities is similar to use of a insulating material. If an air space is left between two layers it acts as a barrier to heat transfer.
Using earthen pots to keep roofs cool has been traditionally practised but the method suffers from practical difficulties and the roof is rendered unusable after installation.
Using earthen pots to keep roofs cool has been traditionally practised but the method suffers from practical difficulties and the roof is rendered unusable after installation.
Proposal
The proposal is an attempt to innovate the traditional method and provide a usable roof with greater thermal comfort. In the technique, inverted earthen pots are laid on the roof and the spaces formed in between are filled with plain cement concrete or lime concrete.
The process followed is concised in the following steps:
1. Clean the roof surface
2. Apply 4 - 5 mm of waterproofing layer
3. Place inverted earthen pots (diameter - 175mm and depth 75mm) on wet cement mortar. Cement:sand = 1:4
3. Fill the void Void space between the earthen pot with mortar bed, till about mid of the pot. Leave it curing for a day.
4. Finish the surface with 30 mm IPS (Indian patent stone) (cement: sand: aggregate = 1:2:4)
5. Make a 20 mm cement mortar bedding (cement:sand - 1:4)
6. Lay it with China mosaic tiling.
7. Fill the joints in tiles with white cement slurry. Wash the finished surface and clean with water
Materials and Rates
1. Epoxy based waterproofing with Fibre glass reinforcement - 33 Rs/sq. ft.
2. Plain cement concrete (1:2:4) 50 mm thick - 99 Rs/sq. ft.
3. Bedding Mortar Cement: Sand (1:4), 25mm thick- 88 Rs/sq. ft.
4. Earthen pots - Rs 5 per piece
5. Ceramic tiles- 25 Rs/ sq. ft.
Total (Material +Labour) - Cost/ sq. ft- Rs 160
The proposal is an attempt to innovate the traditional method and provide a usable roof with greater thermal comfort. In the technique, inverted earthen pots are laid on the roof and the spaces formed in between are filled with plain cement concrete or lime concrete.
The process followed is concised in the following steps:
1. Clean the roof surface
2. Apply 4 - 5 mm of waterproofing layer
3. Place inverted earthen pots (diameter - 175mm and depth 75mm) on wet cement mortar. Cement:sand = 1:4
3. Fill the void Void space between the earthen pot with mortar bed, till about mid of the pot. Leave it curing for a day.
4. Finish the surface with 30 mm IPS (Indian patent stone) (cement: sand: aggregate = 1:2:4)
5. Make a 20 mm cement mortar bedding (cement:sand - 1:4)
6. Lay it with China mosaic tiling.
7. Fill the joints in tiles with white cement slurry. Wash the finished surface and clean with water
Materials and Rates
1. Epoxy based waterproofing with Fibre glass reinforcement - 33 Rs/sq. ft.
2. Plain cement concrete (1:2:4) 50 mm thick - 99 Rs/sq. ft.
3. Bedding Mortar Cement: Sand (1:4), 25mm thick- 88 Rs/sq. ft.
4. Earthen pots - Rs 5 per piece
5. Ceramic tiles- 25 Rs/ sq. ft.
Total (Material +Labour) - Cost/ sq. ft- Rs 160
Demonstration in Surat, Gujarat
Demonstration in Indore, M.P
Video documentation by Taru
This competition was organised by Taru to explore simple and cost effective cool roofing options that are not readily available or popular in India. Read more about the competition here.
Designers
Mansi Shah
Vishal Mehta
Acknowledgements - Taru's Team
Dr. Mahesh Rajasekar - Director at Taru Leading Edge Private Limited
Ashish Mishra
Zeel Patel
Bhaumik Mehta - Contractor, Surat
Mansi Shah
Vishal Mehta
Acknowledgements - Taru's Team
Dr. Mahesh Rajasekar - Director at Taru Leading Edge Private Limited
Ashish Mishra
Zeel Patel
Bhaumik Mehta - Contractor, Surat