I think i'd use subtle blues and/or greens against that brick, which i would use a sealer on to bring up the color a bit. White would be rather boring on the windows i feel, i'd use a darkish muted red or charcoal maybe for this detail. Such a pity to adopt boring western color codes when you have such a fabulous tradition for color in India. You don't have to go crazy on flashy color and can adapt it to a more modern feel. Very cute little house, i love it's details.

In civil engineering this condition is known as efflorescence this condition occurs due to capillary action of water in brick in which water contains diffrent salts comes on surface through voids of brick and evaporates and salt rest on surface as shown in image this salts may be harmful or not this depends on type and chemistry of salts generally it is not harmful

Hello Sajithra, This appears to be smeared mortar. Thanks, Nitin CORNERSTONE DESIGNS Bangalore

AHC , Exposed bricks look definitely add charm to the walls. There are many ways of attaining the same look. Below appears to be a wall paper - it is the easiest way to achieve the look however we do not recommend it . There are brick tiles available and you can get the mounted on the walls for a great quality wall look. Thanks Nitin Cornerstone Designs, Bangalore