How to seal a driveway

By Ralph · Updated June 17, 2026

Sealcoating protects an asphalt driveway from water, UV, and oil — and done right it's a one-weekend job. A typical single-car driveway (about 480 sq ft) takes roughly 3 pails of sealer for two coats and a dry, mild weekend. Here's how to do it, and how much sealer to buy.

When should you seal your driveway?

Sealcoating fills surface pores and lays down a fresh black wear layer that keeps water and sun from breaking the asphalt down. The timing rules are simple:

• Reseal every 2–3 years — not every year. Over-sealing builds a thick, brittle skin that cracks and peels. Wait until the surface looks gray and dry.
• New asphalt needs to cure first. Let a brand-new driveway breathe for 6–12 months before its first seal, so the oils can evaporate.
• Pick the weather window. Apply at 50–90°F on a dry day with no rain expected for 24 hours — ideally a 24–48 hour dry spell. Avoid blazing midday sun, which flash-dries the coat.

A quick test: trickle water on the driveway. If it beads and runs off, the old seal is still working; if it soaks straight in and darkens the surface, it's time.

How much driveway sealer do you need?

Sealer is sold in 5-gallon pails. A pail covers about 400 sq ft per coat on smooth, previously sealed asphalt — less on rough or first-time pavement that drinks the first coat. Because you'll do two coats, a good rule of thumb is one pail per ~200 sq ft of driveway.

Pails = driveway area × coats ÷ coverage per pail

For a 40 × 12 ft driveway at two coats:

• Area: 40 × 12 = 480 sq ft
• Coverage needed: 480 × 2 coats = 960 sq ft
• Pails: 960 ÷ 400 = 2.4 → round up to 3 pails

What you'll need

• Driveway sealer (5-gallon pails) — buy all at once so it's the same batch
• Asphalt crack filler and a cold-patch product for any holes
• A stiff broom, leaf blower, and a hose or pressure washer
• Degreaser for oil stains
• A squeegee/brush applicator (and a smaller brush for edges)
• Painter's tape, and a drop cloth where the drive meets the garage or sidewalk

Step by step

1. Clean the surface. Sweep and blow off all dirt, then wash the driveway and let it dry fully. Sealer won't bond to a dusty or damp surface.
2. Fill cracks and patch holes. Sealer is a coating, not a filler. Fill cracks with asphalt crack filler and pack potholes with cold patch, then let them set per the label.
3. Treat oil stains. Scrub greasy spots with degreaser and rinse — oil bleeds through sealer if you skip this.
4. Edge first. Tape off the garage apron, sidewalk, and grass, then cut in the borders with a brush so you can squeegee the open field without stopping.
5. Apply the first coat. Stir the pail well, pour a bead across the driveway, and pull it in thin, even strips with the squeegee. Thin is the goal — puddles cure slowly and peel.
6. Apply the second coat. Once the first coat is dry to the touch (usually a few hours), apply a second thin coat at a right angle to the first for even coverage.
7. Let it cure. Keep foot traffic off for 24 hours and cars off for 24–48 hours. Cool or humid weather lengthens the cure.

Mistakes to avoid

Related guides

• How much gravel do I need?
• How much concrete do I need for a slab?