Steps to Success

Carefully examine the surface you're planning to paint. Is the old paint peeling and cracked? Are fungus, algae and dirt dulling the colour? Unless these problems are addressed they'll sabotage your new paint job in no time. Careful surface preparation is the foundation of a long-lasting paint job.

Proper surface preparation often takes much longer than the actual application of paint. Be sure to allow for this important step in your budget and schedule.

Dealing with old, lead-based paint

The paint on old houses or buildings may contain lead pigments. White lead was used in house paints until the mid-1950s, and red lead was commonly used in primers until the 1980s. Lead chromate pigments were used in some red, yellow and orange colours, and calcium plumbate pigment was used on galvanised iron and steel structures up to the 1980s.

Though not so common, lead test kits can be purchased from diy and specialist paint stores. If possible, the old lead-containing paint should be left undisturbed and simply cleaned and repainted.

Remove old, damaged paint or stain

Scraping
This is a traditional effective approach for many flat surfaces from smooth masonry and hardboard to wood and ferrous metal. For maximum effectiveness, keep the scraper sharp and apply even pressure as you scrape in one direction, then at 90 degrees. Use shaped scrapers like triangle or oval shapes to get into corners and on rounded profiles. Take care not to gouge or score wood and be sure not to apply pressure when scraping hardboard. For heavier scraping on hard or metal surfaces try a two-hands scraper. Feather sand all rough edges of remaining paint with a medium grade sandpaper to achieve a smooth finish. Wear goggles or face mask for eye protection, leather or work gloves to protect the skin and limit dust intake with a protective mask or respirator. Scraping is less effective on rough surfaces such as stucco.

Wire brushing
A stiff metal hand brush works well on brick, stucco and other masonry. Used vertically it is also effective removing paint from wood shingles. Power wire brushing can be used on stubborn areas, but must be used with extreme care. Wear goggles or face mask for eye protection, leather or cloth work gloves to protect the skin, and limit dust intake with a protective mask or respirator.

Sanding
Areas that have been scraped should be smoothed with sanding. A power sanding tool like an electric belt sander is an option when the substrate is wood or steel. Do not attempt to power sand masonry, hardboard, aluminium or plastic materials.

Power Washing
A high pressure plain water stream is effective in lifting old, loose paint. Never use harsh cleansers or bleach since they can infiltrate the substrates and inhibit paint performance. Hold the spray nozzle 150mm to 200mm from the surface. To prevent damage, spray at a horizontal or downward angle only. Power washing is not recommended for soft woods like cedar and redwood. Wear goggles and water repellent clothing and footwear.

Chemical Removal
Strong solvent-based removers work well on most solvent-based and water-based paints, primers, stains, and varnishes. Apply a heavy coat to a small area, about 0.2 m² at a time, using a low-end natural bristle paint brush. Give it plenty of time to work as recommended by the manufacturer. Carefully remove the softened coatings using a putty knife or wooden blade and scrape the material into a cardboard box. Reapply more stripper if needed and then clean the surface with wadded up paper towelling. Do not use steel wool because it can discolour the treated surface. Use these chemical removers only on small vertical and horizontal face-up areas, such as trim and mouldings. Do not use on face-down surfaces such as porch ceilings. Before using these products, clear the area of children and pets. Cover floors and steps and remove plants, rugs and furniture. Dispose of all waste after the job, carefully following manufacturer instructions. Wear goggles or face mask for eye protection; use chemical resistant gloves, long sleeve shirt and trousers to protect the skin; and protect breathing with a respirator designed for use with chemical solvents. There are low odour alternatives to the strong solvent removers, but they may take much longer, especially if the old coatings are thick and old.

Carefully select your remover. Some are formulated for specific jobs and will not perform well in other applications.

Follow all directions and safety precautions for use and storage of these products. Some products are highly flammable and all fire sources must be extinguished prior to use.

Heat Gun
Old coatings such as paint and varnish can be removed with a heat gun, but special care is required for safety. A dust sheet should be placed on the ground under the entire work area and must be kept damp by periodic misting with a garden hose. Also lightly spray the area of the building where the coating is to be removed. As the old coating bubbles up and softens, carefully remove it with a putty knife. Place the hot softened coating into a metal container for disposal. Wear goggles or face mask for eye protection; use chemical resistant gloves, long sleeve shirt and trousers to protect the skin; and protect breathing with a respirator designed for use with heat gun paint removal.

Do not use a propane torch or a blow torch, as they may pose serious fire hazards. Only use a heat gun designed specifically for paint removal.Do not remove old paint with a heat gun if you suspect it could contain lead. The heat can vaporise the lead and cause a health hazard.

CAUTION: Be sure to take the appropriate precautions when preparing surfaces which may contain harmful materials such as lead or asbestos. See our recommendations under the 'Prepare The Surface' section.

Remove fungus or algae

This spotty black, grey and brown mould is sometimes stubborn to eliminate, but if it is not removed before priming, painting or staining, it can grow through the new coating and ruin your paint or staining job. Fungal contamination thrives in warm, moist, low light environments. Algal contamination on the other hand proliferates is the presence of light. Carefully inspect northern exposures and shaded areas of the house, around the trim and under the eaves, where the sun seldom shines. In addition to fungicidal washes; another effective removal method is to prepare a 3:1 mixture of water and household bleach. Apply the bleach to the fungus or algae allowing a half metre margin around the affected area. Allow it to dry for at least 20 minutes, reapplying as it dries. Rinse the area thoroughly with water and then wash it with a mild detergent and rinse again. Always wear goggles, rubber gloves and old clothes when working with bleach.

Clean the area

Before priming you should remove any dirt, chalk or treated fungus or algae. Scrub the surface area with detergent, water and a stiff bristle brush. Rinse the surface thoroughly, and allow it to dry completely before priming. Another effective surface cleaning method is power washing with water. Never use harsh cleansers since they can infiltrate the substrate and inhibit paint performance. If using bleach to remove the fungus or algae, be sure to wash the area thoroughly and allow to dry before applying paint. Hold the power spray nozzle 150mm to 200mm from the surface to prevent damage, and at a horizontal or downward angle only. Be careful around doors and windows since the spray could have enough force to shatter glass and damage seals. Follow all manufacturer's instructions. Wear goggles and water repellent clothing and footwear.

Prepare glossy surfaces

A new coating may not adhere well to a high-gloss surface, so it is recommended that all glossy areas be dulled for the best primer or paint adhesion. Sanding with a medium grade sandpaper works well for general exterior work. Use fine sandpaper for critical work such as doors and prominent trim. After sanding, remove dust with a damp cloth. Chemical deglossers are also available, but require care and caution. Leaving the product on the surface too long can soften and wrinkle the old coating. Follow all manufacturer's instructions and treat these products as strong solvents exercising safety precautions with protective goggles, gloves and clothing.

Select the primer

The primer coat is critical to a quality paint job. A primer should be used if the surface is very porous or is at all uneven in porosity; or if all chalk cannot be removed from the surface. It is also very effective even when used over sound painted surfaces to maximise adhesion of new coats and ensure the uniformity of gloss or sheen of a finish coat. As a general rule any previously unpainted or unstained surfaces should be primed. And, depending on the surface, a special stain-blocking primer may be necessary. Although both water-based and solvent-based primers are available for most applications, solvent-based primers usually provide superior stain-blocking. Keep in mind that primers have been developed specifically for different surfaces and it is vital that the proper primer be used for wood, masonry, hardboard, or metal substrates and that the primer is formulated for exterior use. Be sure to read manufacturer recommendations about spread rates (how large an area can be covered per litre), drying time before a top coat can be applied, how long the primer can be left before it must be top coated, and how advisable it is to apply a second primer coat. These factors are important to ensure the best finish coat results.

Check all sealant

Chances are if it's time to repaint, it's time to re-seal too. Sealants seal areas where there are gaps in materials or where there were openings made in exterior walls for pipes, wires and light fixtures. Sealant keeps out the elements and insects and gives the house a neat finished look. Inspect sealant around your house and remove any that is old, cracked, or pulling away from the surface. Scrape the area and dust before priming, if the area is to be painted. Apply fresh sealant to all cracks and openings up to 12mm wide. Acrylic or siliconised acrylic sealants are appropriate for exterior use. Silicone types of sealant are durable and suited to exterior use as well, but they should not be painted. For areas where building materials meet that are not going to be painted use a clear acrylic sealant for cosmetic purposes. Allow all sealant to dry overnight and re-apply as needed.

Putty

Check all windows for cracked or loose putty and replace with Linseed Oil putty. Remember to prime the timber window first so that the Linseed Oil is not absorbed into the timber causing the putty to crack. Use a quality water-based or solvent-based primer.

Brushes:

High quality brushes generally have longer bristles and a divider inside to provide a larger paint reservoir for more efficient application of paint, compared with lower quality economy brushes. The ends of the bristles are flagged or split at the tips and the brush is tapered with longer bristles at the centre and shorter bristles to the outside. This means the paint will go on smoother and more evenly. Look for a bare wood handle rather than plastic or painted wood; you'll get a better grip. A rust-resistant metal ferrule that is nailed on instead of crimped to the handle means that you'll shed fewer bristles.

Brushes are available with polyester, nylon or natural bristles. Synthetic bristles are preferred with water-based paints since natural bristles tend to absorb the water in water-based products and lose their shape. Some synthetic brushes are recommended for solvent-based products as well as for water-based coatings. Natural bristle brushes are recommended for solvent-based coatings. Brushes should be pre-primed before use. For painting with water-based products, prime the brush with water. For solvent-based coatings, prime the brush with white spirit. All excess should be removed before dipping the brush into the paint.

Different sized brushes have different functions. Use 30mm to 50mm brushes for trim; 50m to 80mm for doors, 100mm for larger areas such as floors and wall sections, and up to 150mm brushes for broad wall areas.Angular sash brushes are excellent for precise work such as cutting in adjoining surfaces, eg when tackling window frames.

Quality brushes give you a thicker, more uniform paint film for better hiding and durability. And a smooth application will be more resistant to dirt and fungal or algal contamination, than the same paint with brush marks. To sum up a better quality finish.

Rollers:

Quality rollers tend to be thicker and fluffier for greater paint capacity and less dripping and spattering. They also apply the paint thicker and smoother. A higher quality roller will not crack, holds its shape better, does not shed fibres, and is reusable.

For the smoothest application of solvent-based coatings use quality lamb's wool and natural mohair rollers. Synthetic nap rollers are appropriate for water-based paints and some are suitable for solvent-based products. Nap length is also an important consideration. As a rule, short nap rollers from 6mm to 9mm are best for smooth surfaces and long nap rollers from 12mm to 25mm are used for rough masonry.

Sprayers :

If your job is appropriate for a paint sprayer choose a good one. Better sprayers offer excellent uniformity of spray for smooth, drip-free application and are generally more reliable in their performance.

Not all paint is created equal. Top quality paints provide tremendous benefits. They adhere to surfaces much better and hide uneven colouration in the substrate better. They also resist chalking and colour fading, dirt and fungus better than economy paints. And despite costing more per litre, they are actually more economical since they last longer and cost less per year.

Solvent-based vs. water-based

This choice is mostly a matter of personal preference, but it may help to make your choice based on the advantages each type of paint offers. Quality interior water-based paints provide better long-term flexibility and resistance to cracking and chipping. They also tend to resist yellowing with age in areas protected from sunlight. They emit less odour, clean up with water and are not flammable.

Solvent-based paints offer superior one-coat hiding and better adhesion to difficult surfaces such as those not thoroughly cleaned. Solvent-based paints allow for greater 'opentime' or length of time the paint may be brushed before it sets; and superior resistance to 'blocking' or tackiness and abrasion, once cured.

Acrylic vs. vinyl acetate copolymer

If you choose water-based paint, there are acrylic and vinyl acetate copolymer based formulations. A pure acrylic formula offers several advantages including better colour holdout and adhesion in wet conditions, improved grease softening resistance, and better resistance to peeling, blistering, dirt and fungal growth. Resistance to staining from water and foods like mustard, tomato sauce and coffee is another plus along with resistance to alkalinity in household cleansers.

Different finishes

The level of sheen or gloss you select depends as much on appearance as functionality. Each finish has unique characteristics that will highlight or hide the character and construction of the room.

Matt paint is an excellent choice for a uniform appearance across a large area. It tends to hide dents and bumps, but it can trap dirt, stain and create a friendly environment for the growth of fungus more so than a satin or gloss formula. It will also tend to burnish more than other higher sheen finishes.

Silk finishes offer a crisp long-lasting just-painted look and are popular for large wall areas. This finish resists dirt, stains, and burnishing better than matt paint and is suitable for high traffic wall areas.

"Eggshell" or medium sheen finishes tend to be higher performing than general broadwall finishes. This high quality finish resists fungal growth and is ideal for areas where high wear will be inevitable like kitchens and bathrooms.

Water-based interior wall paints are commonly known as "emulsion" paints.

Satin and gloss finishes nicely set off doors, skirting boards, trim and other areas that deserve attention. Gloss paints have higher shine than satin paints. Both finishes are tough and tend to resist dirt and fungal contamination. Once only available as solvent-based paints, more user-friendly water-based alternatives are available today.

Ceiling paints are formulated to diffuse light from lamps and windows and have excellent spatter resistance, but since they have low hiding and scrub resistance they are not recommended for walls. A standard matt paint is also appropriate for ceilings.

There is more at stake in starting a job in fair weather than the comfort of the painter. Paint performs better in mild conditions, in fact poor painting conditions can greatly compromise the paint job even for interior application.

Not too cold

For many paints, the minimum application temperature is 5° C, which applies to the surface being painted as well as the air temperature. Painting at low temperatures, with either water-based or solvent-based paint, will make brushing and rolling more difficult, slow down drying, and leave the wet paint susceptible to capturing airborne dirt, and dust.

Not too hot

Because of the way water-based paints form their film, very hot conditions can make the paint dry too fast and compromise durability. Avoid painting in the following conditions, especially if more than one is present: air or surface temperature that exceeds 30° C, direct sunshine (e.g. window frame applications) especially with dark coloured paint and low humidity.

Not About to Rain

It sounds simple, but many exterior paint jobs go wrong because rain suddenly starts and you have to interrupt your work. Even professional painters often overlook this factor.

A simple solution to a simple problem: check your local weather forecast to find out what the weather is going to be like when you plan to be outside painting. If things look changeable, think of postponing for a few days if you can!

Good ventilation

Most interior wall paints in UK are formulated without solvents; and are commonly known as low odour emulsion paints.

The trim paints and stains market is still divided between solvent-based and water-based products. The odour associated with use of solvent-based coatings tend to linger which can be an irritation especially if the room is not properly ventilated. In such cases, care should be taken to ensure sufficient ventilation during and immediately after the paint job is complete.