It is not a good idea to caulk the lap on your siding. To do so could trap moisture from inside the home behind the siding, causing it to come out through the paint, resulting in peeling.
I occasionally paint buildings where non-galvanized iron nails were used in siding and have rusted, causing a bleeding on the old paint surface. Will an acrylic latex cover these stains and prevent further bleed-through, or must something be done to these nailheads before applying the acrylic latex topcoat?
Stains caused by rusted nails will bleed through the topcoat of even the most durable paints unless a stain-resistant solvent-based or acrylic latex primer has been applied first. If you are painting new exterior construction where non-galvanized nails have been used, it's advisable to spot-prime the nailheads and any knots in the wood prior to applying the topcoat.
If the old paint is peeling, take a good size piece of the peeling paint and hold the edges of it between your thumb and index finger. Exert pressure on both sides of the chip. If it is very flexible and bends easily, it is probably latex. If it is hard, brittle and breaks instead of bending, it is most likely oil-based paint. Another way to test the paint is to wet a rag with denatured alcohol and rub the surface of the paint. If the paint softens or rubs off, it is most likely latex. An alcohol test usually will not affect an oil-base paint.
A primer is beneficial because it helps provide a uniform surface that promotes good adhesion of the topcoat. A primer can also serve a special purpose by sealing a porous surface, blocking out stains, preventing rust formation on iron and steel, and preventing tannin bleed on wood. Most finish paints are designed to provide a decorative or protective finish for a substrate. In most situations, they do not provide the features of a primer, so it is always important to follow the manufacturer''s recommended coating system.
Fisheyes are caused by some type of surface contamination that was not removed in preparation for painting. This contamination can be from body oils, silicone from furniture polish, or any greasy or oil substance. The slippery deposit on the surface does not allow the paint to adhere, causing it to shrink away from the contamination and form a dimple-like void in the paint film.
Try using a solution of one quart household bleach in three quarts of water. Apply the solution to the area with mildew and then rinse off with water. Never add detergents or ammonia to the bleach/water solution. Always protect your skin and eyes against splashes.
If it is not practical to allow the surface to weather for six months before painting, it must be cleaned with a solvent to remove any surface contaminants and oils applied by the manufacturer to prevent oxidation of the zinc in the galvanized coating. This is best accomplished by using a water-soluble degreasing cleaner applied with a clean cloth or sponge. Change sponge or cloth and cleaning solution frequently so the dirt and oil are removed from the surface, not just spread to other areas. Rinse the surface thoroughly and allow to dry before painting.
Until recently, you had to wait one to two months for the stucco to cure properly. However, new-generation masonry primers speed up the process considerably. For instance, Loxon Exterior Masonry Primer from Sherwin-Williams can be applied as soon as the stucco is hard, dry and at a pH level of less than 13. After the primer dries, you can follow with latex house paint immediately.
Handle it the same as you would a regular stucco finish. Loxon Exterior Masonry Primer can be applied as soon as the stucco is hard, dry and at a pH level of less than 13. After the primer dries, you can follow with Duration® or Super Paint. The small glass particles should be imbedded into the stucco enough that they shouldn''t bother the adhesion of the new paint.
No, as long as the siding has had a chance to weather a year before painting. You do need to clean the surfaces first with an Extra Strength Cleaner Degreaser. You want to be sure the surfaces are free of chalk and residue.