Painting Article By Vancouver’s Best Painters

CRACKING AND LATE  STAGE FLAKING

Cracking and flaking are advanced stages of checking. The breaks in the coating penetrate the film completely to the substrate.  On surfaces that have received numerous coats of paint, the underlying layers lose their elasticity and are unable to expand and contract with the surface as it responds to temperature and humidity changes. As the wood swells, stress breaks the bond between layers to form checks.

Additional swelling widens the breaks to form cracks. Because wood expands to a greater extent between grain lines, more force is exerted across the grain. Cracks are therefore more likely to form with the grain.  If the surface is plywood or flat-grain wood, the material itself is likely to crack eventually, which causes the paint film to crack also. Finish coats for plywood should, at minimum, be 100% acrylic latex, but elastomerics are the best of all for plywood.  If paint cracking at plywood joints is severe, caulk the joints with a good grade of acrylic latex or elastomeric-type caulk. This prevents further moisture from penetrating the laminations of the plywood. Failure to adequately prime and protect pressed composition boards and siding can also result in cracking.

Solution

Cracking down to the wood usually requires the complete removal of the coating, re-priming, and re-painting. In cases where cracking occurs over plywood, only periodic scraping, sanding, re-priming, and re-coating will solve the problem.

Latex paints will usually fill plywood cracks better than oil-base materials. Try a latex exterior primer and a good grade of latex finish coat. Pressed composition boards should be primed immediately following installation; adequate coating should be kept on the surface at all times to seal out moisture.

Rick Anderson

www.vancouversbestpainters.com

www.vancouverindustrialpainting.com

www.604painters.com

call: 604-PAINTER

Toll Free: 1-800-PRO-PAINTER

Solutions For Blistering..cont And Checking

If the blistering was caused by moisture, a number of solutions exist. Repair loose caulking and install vents or exhaust fans, if necessary. If the home has lap siding, siding vents can be installed under the siding in areas where blistering has occurred. This will allow moisture from the inside of the house to evaporate before penetrating the wood siding, preventing future blistering problems. Sand and scrape the peeling paint to bare wood; prime exposed areas and repaint. If large areas of the painted surface have blistered and need to be removed, high-pressure washing or the use of a heat gun will speed the removal process.

If the entire house is reprimed, but stands without the finish coat for an extended period of time, more blisters may develop. These should be scraped smooth and spot-primed before applying the finish coat. Blistering is the beginning stage of peeling. Blistering problems and solutions are discussed in more detail later in this module.

CHECKING

Checking (Figure 3) is shallow breaks in the coating film that do not penetrate to the substrate.  Slight checking indicates a relieving of the shrinkage stresses in a paint film. If the film does not check, it may crack due to greater tensile strength and the expansion and contraction of the coating film.  Characterized by a pattern of short, narrow breaks in the top layer of paint, checking usually develops as the paint begins to lose its elasticity. The underlying layers of numerous coats of paint become brittle and no longer expand and contract in response to changes in temperature and humidity. As the wood swells, stress breaks the bond between layers and checks form. Plywood is likely to check because of its construction.

Solution

Remove as much loose paint as possible with a scraper and wire brush and smooth the surface with sandpaper. Use exterior spackle to level material that cannot be removed. If many layers of coating are involved, you should probably remove all the paint to the bare wood to avoid unevenness and prevent rechecking. Prime all bare wood and let it dry; then apply the finish coat. Be careful not to apply it too thickly or when the temperature is too high.

Rick Anderson

www.vancouversbestpainters.com

www.vancouverindustrialpainting.com

call: 604-PAINTER or Toll Free: 1-800-PRO-PAINTER

Notes From Vancouver’s Best Painters:  Call 604-PAINTER (604-724-6837 or

Toll Free: 1-800-PRO-PAINTER

 Solution for Alligatoring of Paint

Remove all paint completely by scraping and sanding. Removal of large areas can be don quickly by power washing or with the use of a heat gun. Make sure the substrate is properl cleaned to remove dust and oils. Prime with either a high-quality latex or oil primer, an paint with either oil or acrylic latex house paint. Make sure the substrate has the propE moisture content and that the paint is dry before it is exposed to additional moisture (de’ rain, etc.)

BLISTERING

Blisters are raised bubbles in the finish surface.  Blisters can be caused by heat or moisture. Painting in direct sunlight on a surface that i too warm causes heat blistering. The film dries too rapidly and trapped solvents late vaporize, bringing pressure against the topcoat and creating blistering. This is more commo:  when using a dark-color coating, since darker colors absorb the heat more readily than lighte ones.  Blistering can also be caused by moisture, particularly in winter months. Interior moisture in tightly constructed homes is a major cause of exterior paint failures. Moisture build up inside the house escapes through the walls because there is no other place for it to go.   In the summer, the sun heats the siding and the water trapped behind the paint film i vaporized. The resulting pressures cause blistering. (Condensation problems are discussed in greater detail later in the posts that follow.

The use of alkyd or oil paint finishes in extremely humid environments with wide temperature variations can cause blistering. Alkyd finishes are sealer-type finishes that restrict the ability of moisture to vaporize and escape through the siding’s surface film Summer sun will cause moisture escaping from the interior of the home to vaporize faster than the alkyd finish coat will allow moisture to escape through its surface. Eventually, this causes blistering of wood surfaces.

One other cause may be the application of coatings over contaminated substrates. Failure to properly remove soluble chemical salts from the substrate prior to coating may result in blistering at a later date.

 Solution

First, determine which type of blistering exists. Break open one of the bubbles. If bare wood shows, the blister was probably caused by moisture; if another layer of paint shows, a heat blister is the most likely cause. In either case, remove the blisters by scraping and sanding In the latter case, the primer coat is generally not affected; you can repaint, without priming when the sun is not shining directly on the surface.

Rick Anderson

www.vancouversbestpainters.com

www.vancouverindustrialpainting.com

www.604painters.com

local: 604-PAINTER 604-724-6837  Toll Free: 1-800-PRO-PAINTER

Vancouver’s Best Painters:  Call: 604-PAINTER

Improper application and thickness control of the paint film can lead to coating failures. These are definitely within the control of the painter.

Moisture can also cause coating failures. These failures can occur as a result of:

•           Painting over wet or moisture-contaminated surfaces

•           Rain falling or moisture condensing on wet or insufficiently dried paint

•           Moisture seeping into a building or structure as result of improper construction Many paint problems, particularly with exterior wood, are caused by moisture, It is important to eliminate sources of moisture and ensure that a substrate is dry before painting. This subject is discussed in more detail later in this module.

TYPES OF EXTERIOR FAILURES

Many types of coating failures have characteristic appearances and specific causes, which are described in this module. The following paragraphs discuss the causes and remedies for most of the coating failures you will encounter.

ALLIGATORING

Alligatoring is seen as pronounced wide cracks over an entire surface. These cracks may not reach the substrate; they may affect a single layer of coating film only. Alligatoring may begin as checking or cracking, but the breaks tend to grow wider at the bottom as wel’ as the top. The topcoating contracts, exposing portions of the undercoat. In an extreme case of alligatoring, the islands of coating between interlacing breaks have not only contracted in area, but have increased in thickness. Consequently, they become wrinkled.

Alligatoring is often caused by failure of the topcoat to bond smoothly to a glossy coat beneath it. A glossy finish is too hard to provide a good bond. In addition, application of an extremely hard coating over a soft primer can result in alligatoring. Alligatoring also may be caused by not allowing time for the undercoat to dry before recoating.

Another possible cause is the natural aging of oil-based paints in extreme climates of freezing and thawing. Also, the moisture absorption/drying-out process, combined with everyday expansion and contraction, results in a loss of paint film elasticity.

Other possible causes include application of a shorter oil-type finish over a longer oil-type undercoat or primer. This problem is magnified if the finish is applied before the undercoat is completely cured. Another cause is a coating that is too thick.

Rick Anderson

www.vancouversbestpainters.com painters painting in the Vancouver area call toll free:

1-800-PRO-PAINTER or visit www.vancouverindustrialpainting.com or call locally:

604-PAINTER

Vancouver’s Best Painters

When a manufacturer makes a mistake with a coating batch that causes it to fall outside specified tolerance ranges, the coating is either discarded or remanufactured to bring it within tolerance. As one might imagine, it is expensive to throw away a batch of 50 to 1,000 gallons or more of coating material. Accordingly, coating manufacturers may do extensive reworking of a batch before deciding to discard it. These “reworked” batches may have more application or performance problems that a coating batch that initially is manufactured properly.

SURFACE PREPARATION

The preparation of a substrate prior to painting is probably the most tedious, expensive, and time-consuming portion of any paint job. It is also the most critical in preventing failures. Prior to painting, the surface must be dry. All oil, grease, dirt, mildew, and other residues must be removed. Surface irregularities must be eliminated or minimized, and holes must be filled. Non visible chemical contaminants as well as aged, brittle, or loose coating material must also be removed. Finally, the surface should have a roughness suitable for good adhesion. If any of these surface preparation conditions is not adequately met, the possibility for coating failure becomes high, particularly if the exposure environment is relatively severe.

When there is insufficient surface preparation, paint may fail because:

•Dirt, debris, oil, grease, mildew, moisture, or old, deteriorated paint prevent the coating

from bonding.

Contaminants such as salt residue draw moisture through the coating to the surface and cause blistering.

            The surface is too smooth for paint to adhere.

            The surface is not sound.

       Cracks or holes, such as bug holes in concrete, cause openings in paint film.

COATING APPLICATION

Most coating materials are applied by brush, roller, or spray equipment. Because successful application depends upon the skill of the craftsperson, failure can occur because of application error. For instance, during spray application, the spray gun should be moved at the appropriate speed, be held perpendicular to the surface being painted, and not be held either too close or too far away. In roller operations, the proper roller nap should be used, and care should be taken not to roll out the paint too much. When brushing, the proper size and shape brush and suitable bristle should be used. It is also important to use the proper technique for dipping the brush and spreading the paint onto the surface.

Vancouver’s Best Painters.

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Vancouver’s Best Painters

CAUSES OF FAILURES

The following is a brief description of some of the causes of premature failures, which may result from substrate conditions, paint material, surface preparation, application, and underlying moisture.

SUBSTRATE VARIABLES

The substrate, or base material over which the coating is applied, may be suitable for some coatings and unsuitable for others. For example, an epoxy coating that may work well over concrete and steel may fail when applied over wood because the wood expands and contracts too much. Similarly, an alkyd coating that is suitable over wood and steel may fail over concrete due to the high alkalinity of concrete. Many substrates can be painted, and each has its own characteristics, including hardness, porosity, flexibility, coefficient of thermal expansion, roughness, pH level, and moisture sensitivity.

COATING MATERIALS

There are many generic coating types. Even within the same generic type, different solvents and pigments can be used to manufacture a paint with modified application and performance characteristics. Just as no single coating material can be expected to resist all environments, no one coating material can be expected to work on all substrates, with all types of surface preparation methods, and in all kinds of weather conditions.

Coating materials are generally formulated to be applied under specific conditions, to specific substrates, and with recommended surface preparation methods. Deviation from the recommended conditions or usages for the paint may result in failure.

On rare occasions, coating failures may be caused by a manufacturing error. When developing a paint, manufacturers test a number of different coating formulations and decide upon the best formula based on cost, performance, ease of application, and other factors. Once that formulation is determined, the paint is made in batches, often consisting of 50 to 1,000 gallons or more.

Resins, pigments, and solvents are added to the batch according to the paint formula. If all of the ingredients are carefully screened for quality, weighed, mixed, and added to the batch as planned, the paint will be consistent with other batches and with the original formulation. However, if any of the ingredients are defective (for example, an improperly-compounded resin) or if something should go awry in the manufacturing process (such as the addition of the wrong pigment or solvent blend), uniformity is not maintained, and a particular batch will be different from other batches. The properties of this batch may cause problems during or after coating application.

Rick Anderson

www.vancouversbestpainters.com

www.vancouverindustrialpainter.com

www.604painters.com

local: 604-PAINTER  Toll Free: 1-800-PRO-PAINTER

 Paint Failure By Vancouver’s Best Painters www.vancouversbestpainters.com

As a member of the painting trade, you will often be called upon to correct finish problems. It is important that you be able to determine what caused a problem so that you can both correct it and prevent it from recurring. This includes recognizing problems caused by improper construction and advising building owners on what to do to correct them. If you are not able to do these things, your work will suffer. You may also find yourself in a situation where you take the blame for a failed finish when the problem was caused by something outside your control.

As you will learn, many finish problems can be attributed to poor workmanship, such as a failure to anticipate problems, improper surface preparation, or improper application of the coating.

However, workmanship is only one of several possible reasons for paint failures. Other potential causes include:

•           Improperly-specified paint (the wrong paint for a given environment)

•           Poor coating specifications, including improperly-specified surface preparation, paint thickness, or application

•           Improper batching or paint formulation

•           Unanticipated exposure conditions such as temperature extremes, chemical contamina­tion, unanticipated abrasion, or mechanical damage

Most often, the problems of workmanship are a result of cutting corners, working too fast, or not doing a thorough job. Here are some problems that arise from poor workmanship:

•           Improper or insufficient surface preparation

•           Mixing and/or applying paint when ambient or substrate conditions are inappropriate (too hot, too cold, too wet, or too windy)

•           Improper or inadequate mixing of materials

•           Application of a coating that is too thick or too thin

O         Curing under adverse temperature or moisture conditions

Virtually all of these application-related problems can be solved by the painting contractor or the company’s workers.

The next few blogs will cover problems related to adhesion on interior and exterior surfaces. As we go on you will receive training on application errors, paint discoloration, and special situations.

Rick Anderson www.vancouverindustrialpainting.com call: 604-PAINTER

Or visit www.604painters.com or www.vancouversbestpainters.com Painters painting in the Vancouver and Greater Vancouver area.  Toll Free: Call 1-800-PRO-PAINTER

8. Which of the following methods can be used to get rid of algae?

a. Avoid painting when there is direct sunlight on the surface

b. Clean the affected area with a bleach solution

c. Use paints that contain a mildewcide

d. Use only oil-based paint in areas where algae is likely to form

9. The use of a colorant intended for indoor use on an exterior surface may result in          

a. fading

b. wrinkling

c. mildew

d. tannic acid bleed

10. If you find mildew on a painted surface, a good way to get rid of it is to

a. scrape it off

b. paint directly over it with a mildew-resistant paint

c. clean with a bleach solution, then apply a mildew-resistant paint

d. spray it with a high-powered hose

11. A pinkish tint is likely to appear on the surface if you    

a. paint over algae without cleaning it

b. do not apply a primer/sealer before painting drywall

c. paint over an aniline stain with a light-colored coating

d. paint over hardboard siding with a light-colored coating

12. Which of the following correctly describes a surfactant?

a. A detergent-like substance in natural wood siding

b. A harmful acid that will damage the finish if not removed

c. A detergent-like substance found in latex paints

d. A discoloration left when leeches crawl across a surface

13. Which of the following conditions is not a recommended method for identifying wax bleeding from hardboard siding?

a. Place a few drops of water on the surface to see if it beads

b. Place a flame close to the surface to see if the wax melts

c. Place a few drops of bleach on the surface

d. Check to see if the surface feels oily

14. True or False? It is a good idea to use a primer containing tung oil on a surface that has previously been decorated with a wallcovering.

15. Before painting over a vinyl wallcovering, you should   

a. sand the wallcovering

b. prime the wallcovering with a semi-clear acrylic sealer

c. prime the wallcovering with an oil-based primer

d. spread a skim coat of topping compound over the wallcovering

these questions were brought to you by Rick Anderson of Vancouver’s Best Painters:  Painters painting in the Vancouver and Greater Vancouver area.

www.vancouversbestpainters.com www.604painters.com www.vancouverindustrialpainting.com call 604-painter

PAINTING QUESTIONS FROM Vancouver’s Best Painters

1. One way to avoid brush marks when you are working on a porous surface is to  

a. use less paint

b. brush harder

c. apply a primer

d. apply the next coat before the first one dries

2. Which of the following is a likely cause of the small depressions known as cratering in a dry paint finish?

a. Painting in cold weather

b. Using a new roller without proper preparation

c. Failure to stir the paint

d. Thinning the paint too much

3. True or False? If cratering occurs, you can easily eliminate it by just painting over the cratered surface.

4. Which of these is a recommended way to prevent bristles from shedding onto the painted surface?

a. Avoid natural-bristle brushes

b. Throw the brush away after the first use

c. Buy top-of-the-line brushes

d. Shake the brush each time before you dip it into the paint can

5. Excessive splatter when using a roller occurs because       

a. the roller pulls the paint up from the surface

b. the roller nap is too short

c. there is not enough paint on the roller

d. the paint has not been thinned enough

6. Which of these problems is likely to occur if you apply paint when the humidity is higher than 85%?

a. Tannic acid bleed

b. Algae

c. Surfactant leaching

d. Sagging

7. When a paint has thickened over the winter, which of the following should you do?

a. Use it as is, but brush it out more

b. Allow it to warm naturally

c. Add thinner to return it to normal consistency

d. Throw it away

These questions about painting were brought to you by Rick Anderson at www.vancouversbestpainters.com cell: 604-painter

PAINTING OVER[: AREAS WHERE WALLCOVERINGS HAVE BEEN REMOVED

Areas previously decorated with wailcoverings may have a residue of paste and/or wailcovering backing if the proper commercial walicovering paste has not been used. Failure to assure proper surface cleanliness can result in staining or discoloration of the paint film. Newly applied paint film may fail to properly cure due to chemical reactions between the resins in the film and the residual paste on the wall.

The paint film may separate into layers, especially if a latex is used. When paint is applied over residual wallcovering backing, the water in the paint reacts with the walicovering paste.

For Painting Over Wancovering Residue

Wall preparation is key. Make sure to remove all walicovering pastes and backings by using a commercial grade walicovering remover or paste remover. If you are unsure of the complete cleanliness of the wall, use a primer containing tung oil and either a latex- or oil-based topcoat.

 PADDING OVER WALLPAPER MW OTHER FLEXIBLE WALKOVERINGS

Problems usually caused by improper surface preparation include dye-bleed, uneven surfaces that have not been spackled, and loose seams.

Solution For Painting Over wailcoverings

When possible, remove old walicovering attached to a solid surface rather than painting over it. However, if wallboard or sheet rock is underneath, paint over the walicovering because wet-stripping can damage those surfaces. When painting textured wallcoverings, be aware that the texture will show through the painted surface

Test for dye-bleed with a finish coat. If dye shows through or the surface is stained, a prime coat is necessary. Oil-based stain-killer/primers are quick drying and work well.

When painting over vinyl or foil wallcoverings, the surface should always be primed. A clear or semi-clear acrylic sealer is best for vinyl; an oil-based primer is best for foil.

When the primer is dry, apply a finish coat of latex or oil. If latex water-based paint is used, bubbles may develop where water reacts to dry areas of wallcovering. Wait to see if bubbled areas dry back against the wall. If they do not, slit the bubbles with a razor blade, remove the loose paper, then spackle and sand. Repaint the affected areas.

Rick Anderson

www.vancouversbestpainters.com

cell: 604-painter

LAP MARKS

Lap marks (Figure 14) sometimes occur where wet and dry layers overlap during the application of paint or stain. This non uniform appearance can be caused by a number of situations such as working too long in one area when painting, too much heat or draft during application, too porous a surface, or the use of an improper thinner. Too much heat or draft causes a rapid loss of solvent and speeds up the setup time, resulting in a thicker film wherever overlapping occurs.

Solution For Lap Marks

Another coat of paint, spread uniformly, is necessary to block out lap marks. If the finish coat is relatively transparent or the surface overly porous, a second coat or a primer coat should be applied.

To avoid lap marks, do not paint one section of a building from top to bottom completely. Instead, paint in small sections as defined by length or width of boards so there is no time for one to dry completely before starting on the adjacent one. However, top to bottom painting is appropriate on siding shingle surfaces since they provide natural breaking points.

Low-luster exterior paints that are highly pigmented require special application techniques. Unless a wet edge is maintained, brushing back into a semi-dry area will double the coat and result in shiners in these places. Work in limited areas to maintain a wet edge, even if it means doing one board at a time.

Painting on hot, windy days speeds up drying time; avoid painting on these days. Add thinner sparingly if it is needed.

Rick Anderson

www.vancouversbestpainters.com

call: 604-painter

Knots that are visible in siding, either painted or stained, are caused by solvents in the wet paint film dissolving the heavily concentrated resins in the knot itself, making them visible through the dried paint film.  Existing resin buildup on the surface of the know prevents latex paints from covering satisfactorily.  Stains, ranging in colour from orange to brown, will appear over the pitchy area of the knot after the coating of paint has been applied.

According to Rick Anderson of www.vancouversbestpainters.com , painters painting in the Vancouver area (call: 604-painter) the solution for pitch bleeding is that new and future coats of paint also will stain unless the knots are prepared properly.  The knots, and the areas aroud them, should be scraped to bare wood before being sealed.  A coat of exterior grade primer sealer or shellac should be applied over the pitchy knot. Finish with the desired topcoat.

Rick ANderson

www.vancouversbestpainters.com www.604painters.com www.vancouverindustrialpainting.com

One cause of discoloration seen on painted hardboard siding is wax bleeding.  Used while manufacturing hardboard siding, wax or petroleum make a board more moisture resistant.  But under certain conditions, the wax can migrate to the surface of the painted board.  Once on the surface, the wax can change the appearance of the board with a wetting effect.  Another cause comes from the surface wax retaining dirt, thereby affecting the appearance of the painted surface.

Some contributing factors are:

The was in the board is more mobile at high temperatures, so dark colour paints tend to exhibit more discoloration because of their tendency to absorb heat.

Areas with inadequate coats of paint are more likely to stain because was bleeding is seen more readily in the thin areas of the brushed or rolled surface.

Paints containing low levels of binder or a non-volatile vehicle are more porous, and are therefore more likely to allow wax migration from the hardboard.

Southern and western exposured are often subjected to direct sunlight; when a surface becomes hot, it accelerates wax bleeding.

In order to correct discoloration, wax bleeding must be identified as the problem.  Some identification methods include:

Wax is not affected by household bleach.  To test this, place a few drops of bleach on the discolored area.  If there is no whitening or bleaching, the stain is probably wax.

Place water droplets on both normal and discolored areas.  If the water beads up and runs off, a wax film is likely.

In sever cases, the wax may be felt as an oily substance.

When cleaning, if surface wax is light or moderate, areas of discoloration can be cleaned with a detergent solutions.  In sever cases, the surface must be cleaned thoroughly with a solvent such as mineral spirits.  The rags should be changed frequently and the surface allowed to dry before painting

When repainting after cleaing, the surface should be primed with an oxidative primer and topcoated as recommended above.

According to Rick Anderson of Vancouver’s Best Painters, painters painting in Vancouver area in BC, British Columbia www.vancoversbestpainters.com and www.vancouverindustrialpainting.com Vancouver Industrial Painters painting in Vancouver alongside 604-PAINTERS of www.604painters.com and Canadas bes painters located at www.canadasbestpainters.com the solution for Wax Bleeding is as follows:

Early painting prevents discoloration.  Unprimed boards should be primed or painted within 30 days.  Factory-primed boards should be painted within 90 days of installation.  The proper amount of paint will minimize problems.  On unprimed hardboard, apply a primer and two topcoats.  Factory primed hardboard may need to be re-primed and then have two topcoats applied.  Paints should be applied at the spreading rate recommended by the manufacturer.

The type of paint selected is critical to achieving good performance.  On unprimed hardboard,use a good quality, oxidative cure primer (such as alkyd or oil).  The topcoat should be first quality and contain sufficient binder to form a tight uniform film.  It may be oi or latex based.  Stains and or shingle and shake paints should not be used on hardboard.  Paints that are specially formulated for hardboard are recommended.  Always apply two topcoats over factory primed hardboard.

Rick Anderson www.vancouversbestpainters.com

Chemical extractives in wood react with metal flashing and produce a stain below the flashing.  Stains can also occur in other areas where the wood surface is in contact with metal;  outdoor faucets, air conditioners, and conduits, for example.

Solution For Flashing Stains

Chemical extractive stains normally can be removed by washing with a mild solution of houshold detergent and water.  Fill any cracks between the flashing and a wood surface with a top quality acrylic or butyl rubber caulk to prevent the stain from recurring.  After the surface is dry, coat with a clear wood finish or other coating or stain.

Surfactant Leaching

All latex paints contain detergent like substance called surfactants.  There are necessary to the paint formula and are used in the process of making paint.  Under certain curing conditions, such as low temperatures or dondensing moisutre, a leaching process occurs which results in a buildup of surfactants on the surface of the paint film.  Surfactants are not part of the paint film, and their coming out of the paint film does no harm to it whatsoever.  In most cases, these substances come out of the paint film slowly and are often washed away undetected.

Solution For Surfactant Leaching

Most often, weathering removes the visible film of surfactant from the surface.  The sheen and colour are then restored.  If washing is necessary (for example, in areas protected from the weather) it should be done only after the surface has cured and well before condensation in the evening can occur.  To hasten the washing process, spray with a fine mist from a garden hose.  The best solution is to do nothing and let nature take its course.  The surfactant does no harm and time will correct the problem.

Rick Anderson Vancouver’s Best Painters www.vancouversbestpainters.com local: 604-PAINTER or toll free from anywhere in North American 1-800-PRO-PAINTER

Dark vertical lines at the bottom of siding shingles are caused by rusting nail heads used to attach the siding to the xterior wall.  Good construction practices call for the use of box nails in siding, but common nails with large heads are often used.  The cannot be countersunk, so they usually rust when excessive moisture is present.

Solution For Rust Stains From Nail Heads.

Rick Anderson of Vancouver’s Best Painters www.vancouversbestpainters.com says that nail heads should be coated with a rust-inhibitive primer before house paint is applied.  If rust has already developed, it must be removed from each nail head with sandpaper and rust-inhibitive primer applied.  If possible, countersink each nail head 1/8 inch below the surface and immediately spot prime.  Fill primed, countersunk holes with caulk or putty.  Removing the stains is almost impossible, but they usualyy can be hidden by another coat or two of paint.  Cover the stains with a rust-inhibitive primer before applying the top coat.

The best prevention against further rusting is to remove the steel nails and to replace them with stainless stell, galvanized steel, or aluminum ones, but this may not be practical.  Rustinhibitive primers are usually effective enough.

Rick Anderson Vancouver’s Best Painters visit us on the web at www.vancouversbestpainers.com or www.604painters.com or www.vancouverindustrialpainting.com or www.canadasbestpainters.com or you can call us locally at 604-PAINTER or toll free at 1-800-PRO-PAINTER.

www.vancouversbestpainters.com www.604painters.com www.vancouverindustrialpainting.com and www.canadasbestpainters.com all state that stains mae with aniline are generally prevalent in older homes and were used primariliy over woodwork and some furniture.  When a light-colored coating is applied to woodwork previously painted with this type of stain, it will produce a pinkish tint.

Solutions For Aniline Stains

The best solution is to seal the stain.  This can be done in one of two ways.  First, test a patch using multiple coats of pigmented shellac.  After applying the pigmented shellac, use a topcoat to determine the effectiveness of using shellac as a sealer.  If the topcoat still has a pink tinge, try sealing with aluminum paint.  Edges may have to be resealed.  This will be effective because of the aluminum paints laminar pigmentation, but it is generally used as a last resort because of difficulties with topcoat adhesion of subsequent coats over the aluminum primer.

Rick Anderson www.vancouversbestpainters.com local: 604-PAINTER or Toll Free: 1-800-PRO-PAINTER

Mildew is not cuased by paint.  It is a fungus that grows on almost any organic surface including painted ones.  Mildew discoloration, which resembles dirt, is actually caused by fungi feeding on oil contained in paints or on thickeners in latex coatings.  Fungi also feed on nutrients in the substrate material, underneath the paint film.  Mold and mildew spores are microscopic and are found universally in the aire, transported by the wind and atmosphere.  These mold and mildew spores can remain dormant indefinitely until conditions are favorable for their growth.  Lengthy perods of warm, moist conditions can activat these spores on what appears to be a perfectly clean surface.  Mildew contaminated homes contaminate ohter homes in the area.

www.vancouversbestpainters.com and www.vancouverindustrialpainting.com says that moisture and warm conditions are the two most important factors in the growth of mildew.  For this reason, mildew generally grows in warm, humid areas with poor air circulation.  Thick shrubbery planted in front of a painted surface can hinder air circulation and block out sunlight, making a perfect environment for mildew to grow.  To determine if mildew is present, drop a small amount of household bleach on the discolored surface.  If mildew is present, bleach will destroy the fungus and whiten the surface.  If the discoloration is simply dirt, the bleach will have no effect.

Vancouver’s Best Painters and www.vancouverindustrialpainting.com both of who can be reaches at 604-PAINTER or toll free; 1-800-pro-painter both know the solution for mildew stains.  Solution:

The mildew must be removed before the painting process begins.  Painting over a mildew laden surface guarantees the return of mildew.  Mildew will grow through any paint film very rapidly; correction may then require complete removal of the coatings.  In extreme cases, you may have to remove the substrate.  Follow the manufactureres instrucations for washing, or use a solution of three parts water and one part bleach.  Commercial mixtures for washing the surface are also available from local suppliers.

After the bleach solution has been applied to the mildewed surface, the surface should be scrubbed to loosen the attached spores.  The bleach solution will quickly change the colour of the mildew when it contacts the spores:  therefore, you must keep a wet bleach solution on the surface long enough to the kll the mildew.  Rinse the affected surface with potable water to remove any residue. 

Repaint with a mildew-resistant paint as soon as the surface is dry.  The addition of more mildewcide to the finish coat may be advisable.  Always paint in dry conditions.  Do not use alkyds or oil based products in these situations.

Rick Anderson www.vancouversbestpainters.com www.604painters.com www.vancouverindustrialpainting.com call: 604-PAINTER or toll free: 1-800-PRO-PAINTER

All colour pigments will fade after prolonged exposure to ultraviolet light, but certain conditions speed up the process. Using a colorant designed for interior use on an exterior surface causes more rapid fading.  The use of a tinting base made with chalking type pigments to make an exterior colour also encourages the problem.  Applying only one coat in a two coat situation is another cause.  Moisture behind the paint film can eventually leach pigment from the film.  Alkali burns on masonry surfaces can contribute to fading.

Solutions For Fading

Once colour has faded, the only solution is to repaint.  Latex finishes are generally better than oil or alkyds for colour retention.  Use colorants formulated for exterior use only, which local suppliers can recommend.  Correct any possible sources of moisture such as cracked caulking or clogged gutters and downspouts. New construction usually requires a primer and a finish coat.

On unpainted masonry, use an alkali-resistant primer appropriate for the intended finish coat.  On burnt surfaces, scrape away as mch of the paint as possible and spot prime the bare spots with an alkali resistant latex primer.  Apply a full coat of primer after this and finish with a latex masonry paint finish coat.  Acrylic paints have proven to be excellent products for color and gloss retention.

Rick Anderson www.vancouversbestpainters.com www.vancouverindustrialpainting.com www.604painters.com

www.vancouversbestpainters.com teaches us that stains on cedar and redwood are due mainly to moisture and insufficient or improper priming.  The resins in certain types of cedar, redwood, and mahogany bleed through paint.  Moisture carries water-soluble colour extractives (tannic acid) contained in the wood through the film.  Staining is more visible when light or medium colours are used.

Two patterns of tannin bleed can occur;  their appearances indicate the source of the moisture.  Rain, dew, humidity, or faulty roof drainage cuase water to penetrate the paint film from the front of siding, crating diffused discoloration.  Water-based house paints also can leach out tannic acid and cause diffused discoloration.  Rundown or streaky discoloration occurs when water finds its way behind the siding.

Solution For Cedar Stain

First, the source of moisture should be located and corrected.  Remove loose or cracked caulking and repair with a quality product.  Avoid caulks that can crack, shrink, or lose adhesion.  Clean out nearby gutters and downspouts.  Wash the stained surface with a commercial-grade bleach solution , rinse with a pressure washer, and allow the surface to dry thoroughly for at least 48 hours.

Prime the dry wood.  Special water-thinned primers formulated to seal in stains are available; alkyd oil based primers are recommended by some manufacturers, as are some acrylic latex stain-blocking primers.  In cases of sever staining, use two coats of primer before topcoating.  A waiting period of at least 48 hours after application is recommended before applying the second coat and or the finish coat.

Most tannic acid stains will penetrate the first coat of primer in seven days, leaving a brownish spot or ring.  If tstains do appear, re-prime the stained spot, allow it to dry thoroughly, and apply the finish coat.  It is a good idea to prime board or siding shingle edges and ends.  If possible, backprime prior to installation.  These procedures will forestall moisture from entering the wood.  If staining occurs during application, sand lighly and re-prime before applying the final finish.

Rick Anderson  www.vancouversbestpainters.com www.604painters.com www.vancouverindustrialpainting.com

There are a number of conditions that can cause paints or staind to become discolored.  The material I will be discussing will show how to recognize and correct problems that cuase discoloration.

Algae

Algae is a growth that occurs where water is readily available to the painted surface.  Usually, algae forms on the lower portions of the norht exterior walls, often around faucets.  Growth requires some indirect sunlifht and is difficult to prevent.  Many paints do not contain an algaecide; also, paint that warranties against mildew may  not contain an algaecide.

Solutions For Algai Discoloration

Clean the affected area with bleach solution as recommended for cleaning mildew.  Power wash after the application of bleach to remove all algae and biomaterial.  Allow the surface to dry completely, then apply a latex paint which contains both an algaecide and a mildewcide.  Check with a local independent decoration products retailer as to the algae-resistant nature of the paint.  Try to identify and eliminate the moisture source.

Rick Anderson www.vancouversbestpainters.com www.604painters.com www.vancouverindustrialpainting.com

A rough, crinkled surface usually occurs when there is interference with the normal drying time of the paint.  If the surface film dries before the bottom layer, the dry film will move and wrinkles will form.  Possible causes of wrinkling include the application of a second coat before the first one is thoroughly dry:  application of a hard finish over a softer coat without priming; painting in the hot sun or over too cold a surface; applying too much paint;  application over a glossy finish; or mismatching materials (eg epoxy on top of an alkyd)

Solutions for Wrinkling Paint suggested by Rick Anderson and Vancouver’s Best Painters.

First, the wrinkled layers must be removed.  If the underneath layers are still soft, they can be removed by scraping alone; but if they are aged, chemical paint removers or other removal methods may be needed.  Areas stripped to the bare wood should be primed and allowed to dry completely before the topcoat is applied.  To avoid wrinkling, bursh out each coat thoroughly and allow it to dry completely.  Deep tones may require more drying time.  Follow the manufacturer’s recommendations.  Do not paint in direct hot sunlight or when the temperature is below 40 degrees F or 5 C.

Rick Anderson www.vancouversbestpainters.com www.604painters.com www.vancouverindustrialpainting.com

If the surface is extremely porous, a prime coat is necessary: otherwise, another finish coat, spread uniformly, might correct the problem.  Some unevenness can be expected on rough surfaces, but additional coats will give better uniformity. 

If moisture contact has caused flattening or if temperature variation has occurred, apply another coat of paint when moisture is not present or when changes in temperature are less likely.  If the undercoat was not dry, allow the flattened paint to dry hard and apply anothe finish coat.

Best Regards

Rick Anderson

www.vancouversbestpainters.com www.604painters.com www.vancouverindustrialpainting.com

Inadequate sealing of surfaces with varying porosity may, after painting, cause a non-uniform sheen.  If shiny spots are noticeable, this problem is sometimes referred to as flashing by www.vancouversbestpainters.com and www.604painters.com Unevenapplication can result in varying film thicknesses and uneven gloss.  Fog or moisture on the paint film during drying flattens high-gloss finishes.  Temperature variations during drying also affect gloss.  Areas surrounding nail heads and wall studs tend to retain gloss because metal conducts heat and speeds up drying time; also, metals are nonporous, which improves gloss.  In addition, painting over a paint film that is not thoroughly dry or that is too soft can cause uneven gloss.

According to www.vancouversbestpainters.com improper amounts of thinner or other addittives sometimes cause uneven gloss.

Rick Anderson

www.vancouversbestpainters.com

www.604painters.com

www.vancouverindustrialpainting.com

According to Rick Anderson of www.vancouversbestpainters.com and www.604painters.com, painters painting in the Vancouver area, sagging has several possible causes.  Applications over a hard glossy finish is a common cause. Other causes include applying too much paint, excessive thinning, or application over a residual film left by a washing compound.

Sagging also can be caused by using too much solvent or using solvents other than those recommended by the coating manufacturer.  Painting cold surfaces will sometimes cause sagging.  According to Vancouver’s Best Painters www.vancouversbestpainters.com and Vancouver Industrial Painting www.vancouverindustrialpainting.com the solution for sagging is to always sand glossy finishes before painting them.  Liquid preparation designed to soften and clean hard coatings are available where sanding dust is a problem.  To determine if the paint is being applied too thickly, use a wet film gauge or measure the square footage covered per gallon of the sagging coat and compare it to the recommended spreading area.  If the rate is too low, increase it by applying a lighter coat or even by thinning the paint if necessary: however, thinning itself may cause the paint to sag.

Sometimes in cold weather, paint stored in cold areas thickens.  Instead of using paint thinner in these cases, allow the paint to warm up naturally.  Do not paint a surface that feels cold to the touch.  Do not paint when humidity exceeds 85%, as drying time will be slower and this can also cause sagging.  If saggin is noted during application despite all precautions, try brushing upward with long, even strokes, wiping the brush after each stroke.

Rick Anderson www.vancouversbestpainters.com www.604painters.com www.vancouverindustrialpainting.com call: 604-painter now!