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Best Paint For Your Home


Paints are the liquid or mastic fluid which on drying form an opaque or transparent thin dry solid film on the applied or painted surface like timber, wood, metals, brick, building, truss, walls etc.

Constitutents of Paint:

·         Pigments: These are solid ingredients which impart colour to paint. Pigments are granular solids incorporated in the paint to contribute color. Fillers are granular solids incorporate to impart toughness, texture, give the paint special properties, or to reduce the cost of the paint. Alternatively, some paints contain dyes instead of or in combination with pigments.Pigments can be classified as either natural or synthetic. Natural pigments include various clays, calcium carbonate, mica, silicas, and talcs. Synthetics would include engineered molecules, calcined clays, blanc fixe, precipitated calcium carbonate, and synthetic pyrogenic silicas.

·         Vehicle: These substances are used to dissolve pigments. The vehicle is composed of the binder; or, if it is necessary to thin the binder with a diluent like solvent or water, it is the combination of binder and diluent. In this case, once the paint has dried or cured very nearly all of the diluent has evaporated and only the binder is left on the coated surface. Thus, an important quantity in coatings formulation is the "vehicle solids", sometimes called the "resin solids" of the formula. This is the proportion of the wet coating weight that is binder, i.e. the polymer backbone of the film that will remain after drying or curing is complete.

·         Drier: These substances are added to help in drying of paint.

·         Thiner: These are the liquids added in the paint to make it thin so that paint can be easily be applied on the surface more easily. The main purposes of the diluent are to dissolve the polymer and adjust the viscosity of the paint. It is volatile and does not become part of the paint film. It also controls flow and application properties, and in some cases can affect the stability of the paint while in liquid state. Its main function is as the carrier for the non volatile components. To spread heavier oils (for example, linseed) as in oil-based interior house paint, a thinner oil is required. These volatile substances impart their properties temporarily—once the solvent has evaporated, the remaining paint is fixed to the surface.This component is optional: some paints have no diluent.Water is the main diluent for water-borne paints, even the co-solvent types.

Solvent-borne, also called oil-based, paints can have various combinations of organic solvents as the diluent, including aliphatics, aromatics, alcohols, ketones and white spirit. Specific examples are organic solvents such as petroleum distillate, esters, glycol ethers, and the like. Sometimes volatile low-molecular weight synthetic resins also serve as diluents.

·       Filler: These are the cheap substances added to paint to increase the quality & quantity of paint.

·       Plasticizer: These are the constituent of the paints to minimize cracking & to give elasticity to the films.



  • To protect the painted metallic surface from corrosion. 
  • To protect structure from weathering action like rain, wind, snow, UV rays, etc.
  • To protect wooden surface from fungus, insects & termites.
  • To impart pleasing appearance to the painted surface.



1.     Water Based Paint

Also known as Latex, it uses water as a diluent. It covers the majority of the paint market in Nepal. It is available in wide range of price and quality and can be used for both interior and exterior painting.

a.       Distemper: It is made of water, chalk, pigments mixed with glue or adhesive.

b.      Emulsion: It is formed by mixing water with emulsifying agent.

c.       Cement Paint: It is powder form of paint mainly used for exterior purpose.


2.     Oil Based Paint

Also known as Enamel, it uses oil, spirit as diluent. It is use for painting metallic and wooden surfaces. It is durable however colour fades after long period of time.


3.     Special Paint

Used for special purpose. For example: anti-fungal paint, fire retardant paint, cellulose paint, heat resistant paint, luminous paint, anti-fouling paint, water repellent paint.


      It should posses a good spreading power.

      It should stick well to applied surface & able to seal porous surface.

      It should dry rapidly to give homogenous film.

      It should form quite tough, uniform, adherent film om applied surface.

      It should protect the coated surface from corrosion & other environmental effects.

      Film must not crack on drying.

      It should be non toxic, cheap, easily available & applicable.



A.   Concrete & Masonry Surface (IS 2395: 1994)

                              I.            Properties of Sub Strata (Clause: 5)

According to IS 2395:1994 (part 1) clause: 5.1, calcareous or concrete surface is highly alkaline. Concrete, lime and cement plasters are likely to cause alkali attackon paint. This will have to be clearly distin- guished from materials which are neutral or nearly so, as in case of calcium sulphate plasters.

According to IS 2395:1994 (part 1) clause: 5.2, there is presence of dampness in the concrete. Its sub clause 5.2.1 explain that the property of final coat depends on initial coat. If the concrete is completely cured, dampness present in it can be neglected which is stated in clause 5.2.2. If there is lack of time for curing, decoration with porous finish such as lime wash, colour wash can be done to continue drying as per clause 5.2.3.

Painting on both side of wall results more risk of paint failure; escape of water is restricted as stated in clause 5.3.

According to IS 2395:1994 (part 1) clause: 5.5, surface imperfection may lead to bad appearance of paint finish.

Clause 5.6 warns for growth of fungi, algae, mould & lichen on damp surface.

                           II.            Surface Preparation (Clause: 7.1)

a.     Lime Plaster

New Surface shall be left unpainted for first few months, so as to allow the surface to dry & harden thoroughly. (clause: 7.1.1)

In case of old unpainted surfaces any source of dampness shall be removed. Any major or minor cracks if presents shall be sealed with putty. (clause: 7.1.2)

In case of previously painted surface, mild detergent is used to wash & light sanding is done. (clause: 7.1.3)

Any existing fungus or mould growth shall be completely removed by scrapping & rubbing down with bristle brush & sand paper, washed & dried. (clause: 7.1.3)


b.    Concrete Surface Painting (Clause: 7.2)

New Surface is left unpainted for as long as possible to allow drying.

Surface shall be thoroughly brushed to remove all dirt & powder material.

Treatment of surface with solution of acid or salt is not advisable because efflorescence may occur.

In case of old unpainted surface, extensive growth of vegetable material may be removed by applying a wash of ammonical copper solution.

Any loose or uneven area or any measure cracks shall be sealed in “V” shape which provides mechanical bonding.

In case of previously painted surface, mild detergent is used to wash & light sanding is done. (clause: 7.1.3)


c.      Masonry Surface Painting (Clause: 7.4)

All mortar joints shall be brought to sound condition.

In case of new brick work, the surface shall not be painted for at least 3 months.

Dirt is removed by washing with water.

In case of old masonary, the extensive growth of vegetable matter shall be removed by ammonical copper solution.

In case of previously painted surface, mild detergent is used to wash & light sanding is done. (clause: 7.1.3)


                       III.            Application of Paint (IS 2395: 1994, Part II)

Wall putty is applied & left to dry for 24 hrs. Sanding is done so the surface would be even& balanced. Primer coat is applied with brush or roller. Wall putty is applied twice followed with sanding so surface would be smoother. Finally the surface is checked & repaired.

First coat of paint is applied in ‘W’ or ‘M’ pattern & allowed to dry. Surface is checked & second layer of paint is applied in same pattern. Final examination is done & final coat is applied to get desired appearance.

A.   Wooden Surface (IS 2338: 1967)

I.                  Surface Preparation (Clause: 6.1) 

The wood should be properly seasoned (moisture <15%) (clause 6.1.1) 

The surface should be well cleaned without any dust, spot, greasy material.

The nails used in wood work should be punched up to 3 mm below the surface.(clause 6.1.2)

The surface is made smooth by rubbing with sand paper of appropriate grade.(clause 6.1.3 & 6.1.4)


II.               Knotting (Clause: 6.1.5)

Resin released from knots is harmful thus the knots need to be sealed.

Any knots, resinous streaks or bluish sapwood present should be treated with two coats of pure shellac knotting.(clause 6.1.5)

Knotting can be done in three ways:

·         Patent Knotting: Knot is sealed by coating with aluminum varnishes.

·         Ordinary Knotting: It consists of two coating; first coat (red lead + water +  glue) & second coat (red lead + boiled linseed oil + turpentine oil)

·         Lime Knotting: Hot lime coat is applied & left for 24 hrs.


III.           Priming (Clause: 6.2)

In this process pores are filled by applying prime coat or first coat.

Recommends at least two prime coat.


IV.           Stopping & Filling (Clause: 6.3)

Nail holes, cracks & joints present are filled by applying putty.

When putty dries & hardens  surface is made smooth by rubbing with glass paper or pumice stone.


V.               Undercoating (Clause: 6.4) 

Underercoat shall be applied after the surface has been primed, stopped, filled and rubbed down to a smooth surface. Undercoat may be brushed or sprayed. After drying the coat shall be carefully rubbed down and wiped clean before the next coat is applied.


VI.           Finishing Coat ( Clause: 6.5) 

The application of finishing paint varies according to the type of paint employed. Cleanliness is essential and as far as possible the application should be carried out in normal dry conditions. The finishing coat may be applied either with the brush or sprayed.

B.    Metal Surface (IS 1477: 1997)

I.                  Surface Preparation ( Part I – Clause: 7 & 8)

·         Removable of Greasy Material: Abrasive paper wetted with solvent like acetone, baking soda, vinegar, 10% formic acid, etc are used. (Clause: 7.1.2)

·         Removable of Rust: Descaling is done by hand scraping or shot blasting but derusting can be done by petroleum, alkaline & emulsion solvent cleansing. (Clause 7.2)

·         Repairing small holes & dent: For small hole inject epoxy based composite directly into hole & for larger hole apply epoxy filler to the edge of hole, place piece of fiber glass appx larger than hole & press into filler. (clause: 8.1)


II.               Surface Painting (Part II – Clause: 4 & 5)

a.      Priming: It is done to prevent the structure from rusting, increase adhesion of paint, protect from environmental factors. It is applied as soon as possible after pre treatment or surface preparation. 

·         Two types of primer: Rust Converters (Lead Based) & Galvanized Metal Primer (clause 4.1)\

·         Paints may be applied by the usual brushes and spray guns. Primer containing lead pigments shall not be applied by spray. (clause: 4.3)

·         Two coats shall be applied allowing a drying time so that the first coat is quite hand dry before the second coat is applied. (clause: 4.4)


b.      Undercoating: After application of the primer, a coat of undercoating is recommended where a high class finish is required. The purpose is to provide a smooth and level foundation for the finishing coat, hide the primer/filler coats and give a full bodied colour in conjunction with the finishing coat.  

c.     Finishing Coat: The finishing coat gives the desired finish to the article. This is the coat which comes in direct contact with the weather and has to protect the underlying coats, which in turn protects the painted article. Choice of the finishing paint shall be made after carefully considering the conditions under which it has to perform. Finishing paiuts/enamels conforming to the relevant Indian Standard specifications shall be employed




·        Efflorescence:

Cause: Moisture present in masonry wall carried the salt to the surface through capillary action. When water evaporates, the white residue of salt appears. (clause IS 2395:1994 Part I, Annex C-2)

Remedy: Remove the efflorescence using wire brush & provide bituminous or metallic seal to avoid capillary action. (clause IS 2395:1994 Part I, Annex C-2)


·        Bleeding:

Cause: Discoloration of paint film due to pigment seeping to the surface from undercoat or resin from knots in timber.

Remedy: Use of shellac or shellac based primer.


·        Peeling/Blistering:

Cause: Painting on direct heat of sun or trapped moisture seeping through the surface or from corrosion site.

Remedy: Avoid painting in hot weather (>84 F) or direct sunlight. Use paint conditioner to slow drying.


·        Cracking & Peeling:

Cause: Inadequate adhesion & flexibility, over spreading or thinning of the paint, inadequate surface preparation, applying to bare wood without primer.

Remedy: Use primer in wood painting. Use a wire brush or paint scraper to scrape off all loose paint. Repainting according to standard.


·         Chalking:

Cause: Resin breaks down due to weathering or painting over porous surface

Remedy: Remove all chalk residue & repainting according to standard.


·         Fungus:

Cause: Growth of algae & fungus due to permanent moisture.

Remedy: Brushing the organism with wire brush, seal the source of moisture, prepare the surface & repainting.


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