Wednesday, October 4, 2023

Low Cost Road ( Cheap Road ) : Construction, 4 Types, Features, Pros & Cons

- Advertisement -
- Advertisement -

When there is an immediate requirement for the road at a low budget, the need is fulfilled by constructing the low-cost road.

Low cost roads are constructed utilizing local labor and materials and can be easily upgraded to blacktopped or concrete roads when traffic increases.

Earth roads, kankar roads, gravel roads & WBM roads are some low cost roads.

What is a low cost road?

✔ The road constructed and maintained at a low cost by utilizing locally available materials & labor is a low cost road.

It is also referred to as a cheap road.

✔ In the villages and underdeveloped areas, the immediate need for roads can be fulfilled at a low cost by these roads and can be improved further if required.


✔ Low cost road commonly focuses on:

~ Minimizing the number of earthworks

~ Minimizing complex and expensive activities

~ Using local and cheap materials

~ Utilizing local human resources

✔ This road is best for underdeveloped areas with smaller investment funds.


Features of Low Cost Road:

✔ Low construction cost 

✔ Use of locally available materials & labor

✔ Easy to upgrade upon the requirement



  1. How many types of low cost roads are there?  

There are four types of commonly used type of low cost roads:

a. Earth Road

b. Kankar Road

c. WBM Road

d. Gravel Road



a. Earth Road 

The type of low-cost road in which pavement structure is constructed with the soil available at the site is called earth road.

 It is also known as the earthen road.

This road is most feasible in rocky areas. It is not suitable in rainy regions.

earth road

Fig: Earth Road


How many types of earth roads are there?

There are two types of earth roads named:

a. Ordinary Earth Road

b. Stabilized Earth Road


i. Ordinary Earth Road  

The type of earth road whose foundation and the wearing surface comprise one or two compacted layers of natural soil along its alignment is an ordinary earth road.

 It is the first stage of road construction.


a. It requires frequent maintenance. Mainly in the rainy season.

b. It is dusty, and ruts are formed quickly.

c. It is not suitable for the movement of weighty vehicles.

d. It is very economical to construct.


ii. Stabilized Earth Road  

The road whose foundation and the wearing surface comprise one or two compacted layers of stabilized soil is called stabilized earth road.

 Stabilized earth roads can withstand high loads and traffic compared to ordinary.

This road is also more durable than ordinary earth roads.


a. It doesn’t require frequent maintenance like ordinary earth roads.

b. Initial construction cost is more as compared to the ordinary earth road.

[ Note:

Stabilized Soil: Soil stabilized with physical, chemical, or biological agents to increase strength and durability  ]



b. Kankar Road 

kankar road

Fig: Kankar Road

 Kankar Road is constructed utilizing kankar (or chips of impure limestone) as the chief material.

 It is only constructed when limestones are available in sufficient quantity.



c. WBM Road 

WMB Road Low Cost Road

Fig: WBM Road

WBM road is the pavement whose surface course comprises crushed or broken aggregates mechanically interlocked by rolling. Voids are filled using filler materials with water assistance.

✔ WBM road produces dust while providing service.

✔ Powder of Calcium Chloride or Bituminous Materials can be spread on the road’s surface to minimize dust.

✔ This road is not suitable for fast-moving vehicles.

✔ In many villages and rural areas, WBM road is constructed initially and further improved or paved when the fund is available.

[ Note:

What does WBM stand for?

WBM stands for Water Bound Macadam. ]



d. Gravel Road 

Gravel Road

Fig: Gravel Road

 A gravel road is an unpaved road surfaced with gravel brought to the site from a quarry or stream bed.

✔ A gravel road is familiar in less developed nations and rural areas of developed countries.



  2. How low cost road constructed?  

The construction of low cost roads includes the following steps:

construction of low cost road


a. Alignment Selection

✔ The alignment shows the path through which the road will pass. So, the selection of road alignment should be made such that it has less conflict, high soil strength & shorter length.

✔ Road alignment is the key factor influencing construction speed and economy.

road alignment

Read Article: Road Alignment with Principles, factors controlling, types, and more. 


b. Cutting & Filling of Earth

Low Cost Road ( Cheap Road ) : Construction, 4 Types, Features, Pros & Cons

✔ Cutting and filling work of earth is carried out to provide proper shape to the road.

✔ During this process, retaining wooden logs (or bamboo) walls are provided if the side slope is unstabilized. In the absence of wooden logs, locally available stones are used.


c. Preparation of Sub-grade


✔ Sub-grade preparation involves soil compaction to increase strength, stability, and bearing capacity.

✔ Compaction of subgrade should be done with the assistance of water.

✔ Road strength is determined by subgrade. So, the subgrade should be compacted multiple times (according to the soil type).


d. Preparation of Pavement Layer

low cost road

✔ Above the subgrade, a material layer (pavement layer) is provided. This layer works as the base as well as the surface course.

✔ No additional layer is required above the subgrade to construct an earth road, as the subgrade acts as the pavement layer.

Road Type Pavement Material 
Kankar Road Kankar
WBM Road Crushed Aggregate
Gravel Road Gravel

 The pavement layer is compacted, similar to the subgrade, with water assistance.


f. Drying

 The road is allowed to dry naturally for 1 to 3 days and then opened to traffic.



  3. What are the considerations for low cost roads?  

The considerations that need to take care of in Low cost roads are as follows:

1. Following the mass curve, The road shall be constructed on a balanced approach.

2. The road shall be constructed in stages.

3. Local materials shall be used.

4. Local workforce should be utilized.

5. Planning shall be done in a decentralized manner.

6. Bio-engineering shall be practiced for slope stability  (instead of a costlier structure).

7. Cross slope of the road shall be towards the outside to avoid the side drain.

8. In the case of natural water resources, a causeway shall be preferred instead of bridges, culverts, or other costlier construction.

9. The garbage and wooden log walls shall be preferred instead of the retaining walls.



  4. What are the pros of the low cost road?  

Some of the pros of the low-cost road are:

1. No significant investment of capital is required. 

2. Local people and materials are utilized.

3. As bio-engineering is preferred for slope protection. It is more environment-friendly.

4. Stage construction technique helps manage disputes at the construction site.

5. The cost of side drain construction can be saved.

6. It helps to mobilize rural materials.

7. It can be upgraded to the blacktopped road when required.



  5. What are the cons of the low cost road?  

Some cons of the low-cost road are:

a. Not suitable for heavy traffic.

b. The requirement of maintenance after heavy rainfall.

c. Low comfort & high vehicle operation cost.



  6. FAQs  

Question  Answer
1. Why is low cost road cheap?  Local labor and materials are utilized to construct this road.

This reduces construction costs.

2. Is this road used in developed countries?  Yes, in rural areas of developed countries, this road is used.
3. How much does this road cost to build?  20 to 25% of the budget for Flexible Pavement
10 to 15% of the budget of Rigid Pavement.
4. Are there only 4 types of low-cost roads?  No, there is no relevant detail regarding how many low-cost roads there are.

We have written only 4 common types of low cost roads in this article.

5. Can low cost roads be upgraded?  Yes, You can easily upgrade.
Read Also: Types of Pavement Failure


Verified Article By Er. Madhu Krishna Poudel
- Advertisement -
Er. Madhu Krishna Poudel
Er. Madhu Krishna Poudel
He is a founder and lead author of Dream Civil International and his civil engineering research articles has been taken as source by world's top news and educational sites like USA Today, Time, The richest, Wikipedia, etc.
Latest Articles
Related Articles
- Advertisement -