Preparing Your Home for Exterior Painting: A Step-by-Step Guide

Step 1: Pressure Washing

Every exterior paint job in the Pacific Northwest should start with a thorough pressure wash. Over the course of a year, your siding accumulates dirt, mildew, algae, pollen, cobwebs, and chalking from the old paint. Paint will not bond to any of that. The siding needs to be clean and dry before anything else happens.

The right pressure matters. Too little pressure and you will not remove the mildew and chalk. Too much pressure and you can force water behind the siding or damage the wood fibers. A good contractor knows the right PSI for each type of siding and uses a mildewcide wash to kill organic growth before it gets sealed under the new paint. After washing, the siding needs at least 24 to 48 hours of dry weather before painting.

Do not skip the mildewcide. In Eugene’s shaded, damp environment, mildew and algae are present on almost every exterior surface. If you wash with plain water, you remove the surface growth but leave the spores behind. A proper mildewcide wash kills the growth at the root and prevents it from returning through the new paint. This is one of those details that separates a prep job done right from one done fast.

Step 2: Scraping and Sanding

Once the siding is dry, every bit of loose, peeling, or bubbling paint needs to be scraped off. This is tedious work, but it is essential. Paint applied over loose paint will peel right along with the old layer — usually within a year. A sharp paint scraper and a lot of elbow grease is the only way to do it right.

After scraping, the edges of the remaining paint need to be feathered smooth with sandpaper. Rough edges show through the new paint and create spots where moisture can get underneath. On wood siding, a hand-sanding or light orbital sanding smooths the surface and gives the new paint something to grip.

Step 3: Priming Bare Wood

Anywhere the old paint was scraped down to bare wood needs to be primed before the new topcoat goes on. This is not negotiable in Oregon. Bare wood is porous and will absorb moisture from the air, from dew, and from rain. Primer seals the wood, prevents tannin bleed from cedar and redwood, and gives the topcoat a uniform surface to bond to.

Use a high-quality exterior primer — oil-based for stain-blocking on knotty woods, or a high-bond acrylic primer for most other surfaces. Cheap primer is a false economy. The cost difference between a good primer and a cheap one is pennies per square foot, but the difference in longevity is years. A $50 gallon of primer that fails in two years is far more expensive than a $70 gallon that lasts a decade.

Do not let a painter talk you into skipping primer to save time. We hear this all the time: “The paint has primer built in, so we do not need a separate coat.” That is marketing language, not reality. Self-priming paints are better than they used to be, but they are not a substitute for dedicated primer on bare wood in a wet climate. If you are painting over bare cedar or fir in Eugene, you want a separate primer coat. Period.

Step 4: Caulking Gaps and Sealing Joints

Every gap, joint, and seam on your home’s exterior is a potential entry point for moisture. Before painting, all of these need to be sealed with high-quality exterior caulk. This includes the gaps around windows and doors, the corner boards where siding meets, the joints where trim meets siding, and any cracks or holes in the surface.

The right caulk matters. Use a paintable, flexible exterior caulk that moves with the wood as it expands and contracts through Oregon’s wet-dry cycles. Cheap acrylic caulk dries out and cracks within a year. A good polyurethane or siliconized acrylic caulk lasts as long as the paint job.

Step 5: Masking Windows, Fixtures, and Landscaping

Protecting everything that is not being painted takes time, but it saves headaches later. Windows need to be masked off carefully, especially if the painter is working around glass. Light fixtures, outlet covers, hose bibs, and door hardware should be removed or wrapped. Landscaping near the foundation should be covered with drop cloths to protect plants from paint drips and cleaning solutions.

A clean job site is a sign of a professional contractor. If a painter shows up and starts painting without taping or covering anything, that tells you everything you need to know about their attention to detail. Good masking takes time — often half a day or more for an average home — but it is time well spent. Paint splatter on windows, driveways, and plants is not just unsightly; it is a sign that the contractor rushed the job.

At Randall J. Banks Painting, we use high-quality blue tape, rosin paper, and canvas drop cloths. We do not use plastic sheeting for landscaping because plastic traps moisture and can damage plants. Canvas breathes and protects without smothering. It is a small detail, but small details add up to a professional result.

Step 6: Dry Rot Inspection Before Painting

This is the step that saves homeowners the most money, and it is the one that gets skipped most often. Once the old paint is scraped off and the siding is bare, any dry rot or water damage that was hiding underneath is fully exposed. A thorough contractor inspects every square foot of bare wood and probes suspect areas with a pick or screwdriver.

If rot is found, it needs to be cut out and replaced before painting. Painting over rot is like putting a Band-Aid over a broken bone — the rot continues spreading underneath the paint, and within a year or two you will see bubbling and peeling right where the rot is. Addressing rot during the prep phase is far cheaper than repairing it later after it has spread to surrounding framing.

How Many Coats Does Your Home Need?

Once prep is complete, the number of paint coats matters as much as the prep work. In Oregon’s climate, two coats of top-quality exterior paint over a proper primer coat is the minimum for a lasting job. One coat is never enough — it is too thin to provide adequate UV protection and moisture resistance, and it will show every imperfection in the surface.

Some contractors quote a single coat to keep the price low and then add a second coat as a “premium upgrade.” That is a red flag. A written quote for exterior painting in Eugene should specify the number of coats of primer (if needed) and the number of coats of finish paint. Two finish coats should be standard. At Randall J. Banks Painting, our exterior quotes always include two coats of premium paint over properly prepared surfaces. No surprises, no upgrades.

The Value of Hiring a Contractor Who Does It All

One of the biggest advantages of hiring a painting contractor who also handles carpentry and dry rot repair is the seamless workflow. When we find rot during a prep inspection, we fix it on the spot and keep moving. The homeowner does not have to find a separate carpenter, coordinate schedules, or worry about whether the rot repair will be compatible with the paint system.

At Randall J. Banks Painting, our prep and repair process is all in-house. We pressure wash, scrape, prime, caulk, mask, repair rot, and paint — all with the same crew. That continuity means nothing gets lost between contractors, and the final result is a paint job that is built to last through Oregon’s toughest weather. We serve Eugene, Springfield, and all of Lane County.

Why You Should Never Skip the Prep Budget

When homeowners get quotes for exterior painting, the biggest variable between bids is almost always how much prep work is included. A low bid is not a bargain — it is usually a sign that the contractor plans to spray a single coat over whatever is already there and move on to the next job. Within two or three years, the paint will fail, and you will be paying to have the whole thing done again.

A properly prepped paint job on an Oregon home should cost more upfront. It involves more labor, more materials, and more days on site. But it should also last two to three times longer than a minimal-prep paint job. When you look at the cost per year of protection, proper prep is the most cost-effective choice you can make.

At Randall J. Banks Painting, we include all six prep steps in every exterior quote. We do not offer a “prep-light” version because we know it does not work in the Pacific Northwest. If you are getting quotes from other painters, ask them to itemize their prep work. If they cannot tell you exactly what they will do to prepare your siding before painting, that is your answer.

The Bottom Line on Prep

Proper preparation transforms an exterior paint job from a temporary cosmetic fix into a long-term protective investment. Every dollar and hour spent on prep returns years of additional paint life. In Oregon’s challenging climate, you cannot afford to cut corners — and you do not have to. A good contractor builds prep into their standard process and their standard price.

If a painter tells you they can paint your home quickly and cheaply, they are telling you they plan to skip the prep. Do business with them at your own risk. If a painter tells you the job will take time and cost a fair price because they do the prep right, that is the contractor you want working on your home.