Vinyl fencing is one of the most DIY-friendly home improvement projects out there. The panels are engineered to fit together — no nailing individual pickets, no staining afterward. Here's how to do it right, step by step.
Before You Dig: The Boring (But Critical) Steps
- Call 811 first. Washington's free utility-locate service marks buried gas, electric, and water lines. It's the law — call at least 2 business days before you dig.
- Check your property lines. A professional survey is cheap insurance against building on your neighbor's land.
- Know the height rules. In Seattle residential zones, fences up to 6 feet generally don't need a permit. Taller than that — or in a front yard — check with the city.
- Talk to your HOA. Many Seattle-area HOAs have rules on fence style, color, and height. Get written approval before you buy materials.
- Talk to your neighbors. Not legally required in most cases, but a heads-up prevents 90% of fence disputes.
Tools and Materials
Tools: post-hole digger or rented auger (~$75/day), 4-foot level, string line and stakes, tape measure, circular saw or miter saw, rubber mallet, wheelbarrow, drill/driver.
Materials per 8-foot section (Smart Fencing kit): 1 post (5"×5"), 1 post cap, top rail, bottom rail, 8 tongue-and-groove boards, 2 U-channels, 1 aluminum reinforcement insert — plus 2–3 bags of concrete mix and gravel per post.

Step 1: Plan Your Layout
Measure your total run and divide by 8 feet to get your panel count. Mark post locations with stakes and run a string line between them — this is your fence line, and every post must sit on it. Mark gate openings now; gates need their own plan (and beefier posts).
Pro tip: Buy 1–2 extra panels. Miscuts happen, and matching dye lots later is a pain.
Step 2: Set the Posts
This is the step that determines whether your fence lasts 30 years or 3. Take your time here.
- Dig holes deep enough for your local frost line and soil conditions, about 10–12 inches wide.
- Add 4–6 inches of gravel at the bottom for drainage — critical in our wet soil.
- Set the post, check plumb on two sides with your level, and brace it.
- Pour concrete, sloping the top away from the post so water runs off.
- Let the concrete cure fully before hanging any panels. Don't rush this.
Keep post tops at a consistent height using your string line — or plan to trim later.

Step 3: Install the Rails and Panels
- Slide the bottom rail between the posts.
- Insert the U-channels on each post — these frame the boards neatly.
- Slide the tongue-and-groove boards in one at a time, starting from one end. They should fit snugly without forcing.
- Drop in the aluminum reinforcement insert (this is what keeps long spans from sagging).
- Set the top rail, then press on the post cap.
Work one section at a time, checking level as you go. On slopes, step each section down rather than trying to follow the grade — it looks cleaner and panels stay level.
Shop styles and pricing or book a free consultation — we also offer professional installation.