- Portland (503) 384-9100
- Seattle (206) 652-4200
Exterior trouble shooting FAQ
Q: I have tried everything I can think of to keep paint on exterior window sills. What do you suggest my painting contractor do?
A: The painting contractor should prepare and repaint the entire window unit. The painting contractor must remove all loose paint with a wire brush or scraper, this includes the ends and underside of the sill, as peeling or cracking often begins there. Next, your painting contractor must remove any old failing caulking from the joints in the frame and the areas where the frame meets the sill and where the frame and sill meet the siding. Finish the surface prep by removing all loose particles from the sill. Now the painting contractor must apply one coat of exterior slow drying alkyd wood primer, again paying special attention to the end grain and underside of the sill. After the primer dries, apply an acrylic latex caulk to the joints where previous caulking was removed in the frame, the space between the frame and sill, and the space between the window and the siding. The painting contractor must follow with one or two coats of a top-quality acrylic latex flat, or satin house paint.
Q: Can mildew be permanently prevented by a painting contractor?
A: No. A Painting contractor cannot prevent mildew reoccurrence. However paints can be formulated to inhibit mildew growth, but under some conditions, mildew eventually will reappear on any type of paint.
Q: I am experiencing a great deal of peeling under the eaves of my house. Is moisture the culprit or do you think my painting contractor failed to properly prepare the surface the last time my house was painted?
A: The eaves of a house are a frequent location for paint problems, with peeling topping the list of concerns. Moisture drawn out of the house sometimes is the source of the problem, but more times than not the culprit is lack of inter-coat adhesion. This occurs when painting contractors apply paints to old, and when dirt and contaminants, such as salt, is not properly removed prior to painting.
Q: Why does wood fencing darken significantly when left unprotected, did my painting contractor do something wrong?
A: Ultra-violet radiation from the sun causes wood to naturally darken. For wood surfaces that have never been coated, or which have been finished with clear varnishes or lightly pigmented stains, this darkening can be unattractive. Unfortunately this problem cannot be solved by a painting contractor
Q: The following day after my painting contractor finished painting the siding on my house, I noticed wrinkles in various areas of the finish. What did my painting contractor do wrong?
A: If your painting contractor applied excess of the recommended wet film thickness or two coats of paint were applied too quick. This will not allow sufficient drying and wrinkling may occur. This surface imperfection should be corrected by the painting contractor once the paint film has dried by power sanding. The smooth area should then be primed with a quality oil or latex primer prior to top coating.
Q: After a painting contractor painted my aluminum siding with a latex house paint, there where sections of the house that contained streaks. What happened?
A: When dew forms on latex paints before the film has fully cured, a concentrated residue from the paint material can form on the surface, causing staining, unsightly runs and gloss patterns. This finish problem is known as surfactant leaching. Aluminum siding is particularly prone to surfactant leaching because this type of substrate reacts to temperature changes faster than wood. To avoid this problem, your painting contractor should apply paint during temperatures that allow proper curing.
Q: My new stucco house was just painted by a painting contractor and now has unsightly stain streaks. Do you know what possibly could be causing this?
A: Stucco and mortar joints contain hydrated or "hot" lime, a dry compound added to improve the workability of these materials. If the high alkalinity of mortar, cement mixes and concrete is not addressed prior to painting by your painting contractor, a reaction can occur when moisture is present, resulting in blistering, peeling and burning stains.
Q: What causes reddish colored stains on cedar and redwood?
A: The culprit here is a water-soluble dye called tannin. Moisture in the wood will cause the tannin to migrate to the surface and stain the paint. New red-colored wood must be sealed with a quality alkyd or latex under coater to create a barrier between the topcoat and the wood. More severe cases of tannin bleed may need one or two coats of an alkyd primer to prevent discoloration. Your painting contractor will be able to correct this problem
Q: Why do doors painted with latex paint sometimes stick to the weather-stripping? Did my painting contractor make a mistake?
A: Latex paints contain chemicals called plasticizers that allow proper film formation and keep the coating flexible. Many vinyl and plastic weather-stripping materials also contain plasticizers to give them flexibility. When two surfaces containing plasticizers come in contact with each other, they can have the tendency to stick. This condition, known as blocking, will generally occur during the early curing time of the coating, but it can continue for some time. Blocking can also occur on double-hung windows and garage doors. The way a painting contractor will prevent blocking is to use a non-blocking acrylic, or alkyd base paint in areas where it may occur, also proper ventilation to these areas during the drying period are critical.
Q: What causes white powdery deposits on masonry surfaces, and how can I fix them?
A: The deposits, known as efflorescence, are caused by moisture in the masonry. The moisture dissolves salts in the masonry -- the mortar, block, concrete, etc. -- and is drawn to the surface by the heat of the sun. The water evaporates, leaving behind white deposits that must be removed before painting. After your painting contractor finds and fixes the source of the moisture, the painting contractor must remove the efflorescence with a wire brush and coat the surface with a masonry primer and topcoat.
Q: What causes small cracks to form on a recently painted wall?
A. This problem is commonly called "alligatoring." The most common cause of alligatoring is the application of too thick of a paint film. The surface of the film dries first, with the rest of the film taking longer to dry than normal. When the underside of the paint finally does dry, it shrinks, causing the top of the film to pull apart and leaving unsightly cracks. A painting contractor can prevent this by applying the paint at the manufacturer's recommended thickness and spreading rate. A less frequent cause of alligatoring results from painting over a contaminant on the surface such as oil, silicone, body oils, hair spray, etc. A painting contractor can prevent this by thoroughly cleaning the surface before painting.
Q: Why after one year am I getting discoloration on some areas of pre-primed finger jointed wood-work coated with a latex semi-gloss?
A: The most likely cause of the discoloration is the resin in the glue used to hold the wood together. If your painting contractor applies and primer to the wood before the latex semi-gloss, it will usually lock this in the resin, but sometimes the contractor will need to resort to an alkyd stain killer, or even a pigmented shellac stain killer in severe cases.
Q: After a new home is painted by a painting contractor and the wood shrinks along with the caulk, is it normal to need to re-caulk and/or repaint before the first year?
A: With the settling you get in a new house and as the wood dries and shrinks, you're bound to have some places that will need touched up with more caulk and paint. Usually after the first year, you won't have any more shrinkage. Make sure your painting contractor uses a good acrylic latex caulk that is flexible and will withstand some movement in the joint.
Q: My vertical wood siding house was recently painted white by a painting contractor, and now I notice rust staining from nails. What did my painting contractor forget to do?
A: If steel nails or uncoated steel hardware is exposed to air or moisture, unsightly stains can develop on adjacent paint surfaces. This problem is easily rectified and avoided if the painting contractor wire brushes or sands the metal clean and applies a rust-preventative primer. The painting contractor should also caulk deeply recessed nails with a good acrylic latex caulk.
Q: My new cedar house is being painted by my contractor and I have noticed discoloration of the paint film after the paint dried. What could be causing this to occur?
A: Red-colored woods, such as redwood and cedar, contain a water-soluble dye called tannin. If latex topcoats are applied directly to these wood surfaces, a reddish discoloration may form through the paint finish. Discoloration may also occur on these woods by water migrating to the surface. Your painting contractor must use a slow drying alkyd primer to block these stains before applying a latex finish coat.
Q: What usually causes a coating to fail?
A: The most frequent causes for premature paint failures are due to a painting contractor failing to do sufficient surface preparation; not applying enough paint; using an improper coating; not applying the product as directed; or environmental conditions (moisture, fumes, chemicals, etc.).
Q: Why is it so difficult to keep paint from peeling off of exterior wood decks?
A: The culprit here is moisture. Usually, only the top and ends of the boards used on a deck are painted. This leaves the sides and bottom uncoated and able to absorb moisture from rainfall and the soil under the deck. The moisture, drawn to the surface by the heat of the sun, destroys the adhesive bond between the wood and the paint, causing it to blister and peel. The best way for your painting contractor to protect a new deck is to apply a deck sealer/toner or semi-transparent stain to all the raw material before the deck is built, to thoroughly seal all surfaces. The painting contractor should then re-stain/seal the deck once the deck is assembled.
Q: About a year ago, I had a painting contractor clean and refinish my pressure treated deck with a clear water repellent. It looked like new when the painting contractor finished it, but a few weeks ago I noticed it was turning gray again. Did the painting contractor do something wrong?
A: Your painting contractor probably didn't provide the wood with any protection from the damaging effects of the sun's ultraviolet (UV) rays. Clear water repellents do a great job of protecting wood from damage caused by water, but they usually don't provide any UV protection. Wood that is not protected from UV rays can turn a silver gray color in as little as six months. After you use a deck cleaner to restore the wood to a "like new" look, apply a finish with UV protection. If you want to change the color of the deck, have your painting contractor use a semi-transparent stain or a toner. For a clear, natural wood look, try one of the new clear wood finishes that offer UV protection. Many are water reducible for easy clean-up. Note that most semitransparent stain products will only protect for a couple of years before the graying returns.
Q: How should my painting contractor determine the difference between wax bleed and mildew on hardboard siding?
A: Your contractor should clean the area with a mixture of three parts water and one part house hold bleach. If it comes clean, it's probably mildew. If your contractor sprays the area with a spray bottle filled with water (like an old window cleaner bottle) and the water beads up and slides off, the problem could be wax bleed. To further complicate the issue, many areas affected by wax bleed will easily mildew. Because of the sticky wax on the surface, mildew attaches to it very easily.
Q: I was disappointed to find that the paint my painting contractor applied over the caulk around windows of a house cracked. What didn't my painting contractor do right?
A: When the painting contractor applied paint over a partially dried bead of caulk, the paint forms a film first. As the caulk continues to dry, it separates from the underside of the paint film, resulting in cracks. To prevent this surface defect, the painting contractor must allow sufficient time for the caulk to dry prior to painting. Conditions that affect the drying time of caulks are high humidity, wide joints in excess of 1/2 inch in width or depth, and low temperatures (below 40° F).
Q: Last fall, my house was painted by a painting contractor with a glossy oil-based exterior paint. The job looked fine when I finished around 5 p.m.; but when I looked at it the next morning, some areas were glossy, some flat. What happened?
A: Since your painting contractor finished painting late in the day, during a season when the temperature usually drops dramatically as soon as the sun goes down, I suspect that moisture was the culprit. In the spring and fall, condensation (dew) forms on surfaces that have been warmed by the sun during the day, then cooled quickly when the air temperature drops after sunset. Using a glossy oil-based paint, which typically takes longer to dry, can compound the problem. The slower drying time allows moisture to get into the paint film before it's fully cured. The result is an uneven, mottled appearance. The problem can usually be fixed by having the painting contractor allow the paint to dry for a couple of days, then have the contractor apply another light coat of the same paint. The contractor must allow this coat to dry for several hours before the sun sets and the temperature drops to prevent a reoccurrence of the problem.