Mud construction is the use of unfired clay. Mud is one of the oldest construction materials ever used. Even today in India around 58% of the population uses mud as the primary construction bulk. Although, mud is considered as a weak and unsustainable material by the common folk, modern construction techniques and improvement of mud as a construction material has managed to do away with its cons, leaving behind only the pros to enjoy. Therefore if you think that it is a poor man’s resource and is suitable for rural huts only- you are very wrong.
Know before you choose mud
If you are seriously looking for a sustainable mud construction, the delights of mud are many.
- Energy efficient, as the entire energy employed to bake the bricks in kiln is saved-mud bricks are baked under the sun
- Cost effective mud is a cheaper material- Rs 150/sq ft for brick is much higher compared to Rs 20/sq ft for mud.
- Interior temperatures are low keeping down electricity use.
- Recycle and Reuse– add some water and it is back to its plastic form again.
“You can’t get more sustainable or renewable a resource than mud. Approximately 58% of all buildings in India today are made of mud brick, some as many as 50 to 100 years old. Mud is gathered either at the construction site or very nearby, formed into bricks and dried in the sun. It is readily available and can be made by people with limited initial training—all resulting in projects that can be built at a fraction of the cost of those using concrete and steel.”-Laurie Baker.
However there are few primary disadvantages associated with construction which employs only mud:
- A straight pure mud construction is viable to damage due to heavy rains hence not suitable for regions affected by storms and floods.
- Prone to termite attack, which often leads to deterioration of timber products in the house.
However these problems have been done away with the various new and ancient technologies associated with mud construction. So, if you are looking for a green, eco-friendly home amidst the city– This should be the choice of material.
Why and when will you choose mud?
- Mud houses are cheaper to build.
- They are eco-friendly and promote healthier living.
- Well insulated-cool in summer and warm in winters.
- You will be contributing towards a better environment.
- Mud houses are very elegant and aristocrat.
- So, if you are suffering from a mere prejudice that a mud house will make you look a stone-age man, shun it all off and be proud cause you have contributed towards the environment.
What ways can mud be employed?
Gravely soil containing 60% sand is mixed with straw and other fibers .Cob is normally applied by hand in large gobs (or cobs) for the building process. This kind of wall is prone to cracks. It is good for anything but height. Cob wall structures are low and rounded in form with projected roofs.
It consists of using a mould with two parallel boards to compact the earth inside them, such that in situ wall construction is achieved. This technique is usually suitable for single storey houses.
Wattle and Daub construction
This is a commonly used technique, where bamboo is available in plenty. It essentially consists of a bamboo framework with mud filling. The horizontal provides two surfaces with 10 cm round bamboo in the middle. The horizontal and verticals are tied together using coir. Wet mud is now applied to the frame to complete the mud wall. The finished thickness is about 15 cm.
Wattle and daub construction is supported by a cane structure, therefore it is efficient in supporting cyclones, seismic waves and floods. Even if the mud washes away the bamboo structure remains intact.
Adobe Wall construction:
Adobe refers to sun dried bricks made from sand, clay and water with some kind of fibrous or organic material (sticks, chopped straw & dung). It is better than cob walls as it is not prone to shrinkage. Adobe bricks can be easily employed to build a two storey house.
Pressed bricks which are a modified form of adobe with added stabilizers and compaction can easily support a three storey building.
Earth Bag construction:
The use of earth bags to build houses it relatively a recent phenomena. It has been used over a century to control flood waters but its use in residence was brought about by Nader Khalili.
Earth bag construction is an inexpensive method to create structures which are both strong and can be quickly built. Earth bag building uses polypropylene rice bags or feed bags filled with soil or insulation that are stacked like masonry and tamped flat. Barbed wire between courses keeps bags from slipping and adds tensile strength. The final plastered walls look just like adobe structures.
Stabilized mud block or Compressed Stabilized Earth block:
These mud blocks are resistant to water and do not soften easily under the action of water due to the addition of stabilizers which act as binding agents. Stabilizers may include cement, lime, pozzolana and flyash. The performance of such blocks depends on density therefore the compaction is necessary to make it dense in moulds under adequate pressure.
These can be employed just like your bricks.
Mud construction often can do without an added ornamental finish.
However it is always necessary to apply a layer of protection. Two or three coats of whitewash or sieved earth mixed with lime or cement will do the job. One can also mix colouring matter.
Exterior walls or bathrooms and floors are often fall prey to corrosion. It is always commendable that certain walls are plastered and bathrooms are tiled.
Colour and interiors
Sport the nude mud bricks in the certain walls. Shades of yellow, ash and grey blue go well. Do your interiors with traditional handicrafts. Terracotta glazed tiles can be used for tiling purposes.
A few dos and don’ts
- Compressed stabilized houses or adobe can support pitched or concrete roofs.
- Roof should preferably be sloping and should project outwards. This is done with regard to prevention of rain water from wetting the walls.
- Floors can be plastered or tiled.
- Exterior walls should be plastered is case of cob construction.
- Roofs should be either tiled or plastered.
- A naked open mud top leads water to seep in.
- Bathroom floors should be tiled covering and sealing the nooks and joints properly.
- Plinth level should be kept high. This not only keeps away water from seeping into your house but also keeps the room cool.
- Window stiles and heads i.e. the exterior frame should preferably be kept metal or polymer based, if you are sporting a nude mud brick interior. Wooden frames are prone to termite attack.
- If you are living in a dry zone or are using CSEB blocks for your exterior, you can easily sport a nude mud brick wall with the minimal use of paint and plaster.
- Mud houses might do without steel reinforcements. But then you have to be careful in working out structural requirements. Columns play a major role in supporting structural load.
- If you are building a lavish, large establishments steel reinforcements can be used as it is used with normal bricks.
- Mud is not suitable for heavy structural work like skyscrapers and bridges and it is obvious why.
- Mud houses can be made 100% eco-friendly with using rain water harvesting techniques, lowering down use of air conditioners and fans.
- Have your own vegetable or flower patch in a garden. It not only adds to the beauty but also prevents erosion.
So next time when you are looking for a house, go for a mud one. Good Luck!