The preparation phase of the exterior painting is the most important stage. Scraping or sanding is the most common practice when preparing a house for paint.
Scraping will remove the larger loose or raised areas and is completed before sanding. The sanding of any surface can be completed by hand sanding, or power sanding.
Hand sanding is most commonly done when the peeling paint or stain is minimal, or the surface area is small with many angles or different levels.
Areas such as gutters, fluted columns, columns, dental moldings, crown moldings, louvered vents are a few of the items that are commonly hand sanded.
EPA guidelines require any painted surface older than 1978, be hand scraped only due to the lead paint laws and no sanding should be done.
The term Feathered edge is used to describe the edge of the old paint where it meets bare wood. The technic is to sand the painted edge to a tapered transition to the bare wood. A feathered edge will be smooth to the touch and have no jagged abrupt lines between the wood and old paint.
Scraping only, when done on older homes with lead, will give you an un-feathered edge leaving a defined jagged edge between the old paint left intact and the bare wood.
Power sanding is a much more aggressive and faster way to prepare a surface for paint.
There are many sanding machines available and each has their own pros and cons and should be researched before choosing which one to use.
We suggest using a random orbital, this machine is more forgiving and will provide a very smooth surface with very little circular marks.
A grinder or disc sander is used when the peeling paint or stain is severe and has multiple layers of paint.
Grinders or disc sanders can damage the wood surface and leave very pronounced swirl marks if used by a apprentice or homeowner and is only suggested to be used be professionals.
Surfaces most commonly prepared with a power sander is decking, clap board siding, shingle siding, trim.
When using a power sander, the grit should be tested to make sure that it will not damage the substrate. A feathered edge is much easier to accomplish by using a power sander.
Priming is completed to assure proper adhesion for your top coat. Primers are universal and both Latex and oil paints can be applied over any primer. Most paints require priming of bare wood with full prime coat.
Oil primers or Under body primers are the safest to use on exterior surfaces as they have the ability to hold back Tanaan bleed that can come from exposed natural wood. Knots in wood require a shellec based product either clear or white to stop the knot from bleeding through the paint.
Primers are not sufficient to hold back knot bleed. Rust requires a Rust Stop product and then a primer, rust will bleed through primer coat only.
Choosing the proper primer is also very important step to assure that your finish coat has the best opportunity to last the longest period.
Finish paints have different product and sheens and are recommended to be applied over certain surfaces.
First identify the surface that you are top coating, wood, cement, Azek, shingles, clapboards, decking.
After you have identified the surface, you will need to determine the paint brand that you would like to use, we recommend either Sherwin Williams or Benjamin Moore.
We recommend for previously painted wood trim surfaces with either oil or latex to top coat with a 100% Acrylic latex.
Always choose the highest quality product from the manufacture that you have chosen.
The easiest part of any project is the finish coating, and to use a lesser quality paint can minimize the duration of the paint job.
