What is Thermal Insulation of Buildings?
In general, people living in hot regions wants to make their inside atmosphere very cool similarly people living in cold regions, wants warmer atmosphere inside. But, we know that the heat transfer takes place from hotter to colder areas. As a result, heat loss happens. To overcome this loss in buildings thermal insulation is provided to maintain required temperature inside the building. The aim of thermal insulation is to minimize the heat transfer between outside and inside of building.
Materials and Methods of Thermal Insulation of Buildings
There are many forms of thermal insulation materials are available in the market as follows:
- Slab or block insulation
- Blanket insulation
- Loose fill insulation
- Bat insulating materials
- Insulating boards
- Reflective sheet materials
- Lightweight materials
1. Slab or Block Insulation
The blocks are made of mineral wool, cork board, cellular glass, and cellular rubber or saw dust etc. These are fixed to the walls and roofs to prevent heat loss and maintains required temperature. These boards are available in 60cmx120cm (or more area) with 2.5cm thickness.
2. Blanket Insulation
Blanket insulation materials are available in blanket shape or like paper rolls which are directly spread over the wall or ceilings. They are flexible and having a thickness about 12 to 80mm. these blankets are made of animal hair or cotton or wood fibers etc..
3. Loose Fill Insulation
Stud space is provided in wall where windows and doors are to be provided. In that studding space of wall loose fill of some insulating materials is provided. The materials are rock wool, wood fiber wool, cellulose etc.
4. Bat Insulating Materials
These are also available as blanket rolls but bat insulating rolls are having more thickness than blanket type materials. These are also spreader over the walls or ceilings.
5. Insulating Boards
Insulating boards are made from pulp of wood, cane or other materials. These pulp is pressed hard with some stress at suitable temperature to make it as a solid boards. They are available in many sizes in the market. And these are generally provided for interior lining of walls as well as for partition walls.
6. Reflective Sheet Materials
Reflective sheet materials like aluminum sheets, gypsum boards, steel sheet Materials will have more reflectivity and low emissivity. So, these materials are having high heat resistance. The heat gets reduced when solar energy strike and gets reflected. These are fixed outside of the structure to stop the heat entrance into the building.
7. Lightweight Materials
By using light weight aggregates while preparing concrete mixture will also results good results in heat loss preventions. Concrete will have more heat resistance if it is made of light weight aggregates like blast furnace slag, vermiculite, burnt clay aggregates etc.
Other General Methods of Building Thermal Insulation
Without using any thermal insulating materials as said above we can achieve the thermal insulation from the following methods.
- By providing roof shading
- By proper height of ceiling
- Orientation of building
8. By Providing Roof Shading
By providing roof shading for the building at the place where sun directly strikes the building during peak hours, we can reduce the heat by shading of roof. Accurate angle should be provided for shading to prevent from sun light.
9. By Proper Height of Ceiling
The heat gets absorbed by the ceiling and emitted downwards that is into the building. But, the point should be noted is, the vertical gradient of radiation intensity is not significant beyond 1 to 1.3 m. it means it can travel up to 1 to 1.3 m downward from the ceiling. So, provision of ceiling at 1 to 1.3m height from the height of occupant will reduce some heat loss.
10. Orientation of Building
The building orientation with respect to sun is an important thing. So, the building should be constructed in an orientation in such a way that it shouldn’t subject to more heat losses.