How Much Sealer Do I Need? Coverage, Sand, Water and Coats

The answer to "how much sealer do I need" is one formula: pavement area divided by the data sheet's concentrate coverage, times the coats, plus a waste factor, rounded up to the drums or totes the supplier sells. SealMaster's MasterSeal TDS rates a gallon of concentrate at 100 to 120 sq ft per coat, so a 1,200 sq ft driveway with two coats needs 24 gallons at the low end. Water, sand and additive come from the same sheet.

How much sealer do I need: the formula and the two coverage numbers

You need area times coats divided by coverage, and the coverage must be the concentrate figure, because that is what you buy. The MasterSeal TDS prints both on one page: a gallon of concentrate covers approximately 100 to 120 sq ft per coat, and the mixed material (concentrate plus water, sand and additive) goes down at 70 to 82 sq ft per gallon. Divide by 70 and you order a third more concentrate than the job takes.

Pricing the gallons is a separate job, covered in How to Price Sealcoating Per Square Foot; this post stops at the order.

Step 1: Square footage, minus islands and buildings

Start with pavement only, with every planted island, building footprint and dumpster pad taken out, because a gallon covers pavement. AsphaltPro's commercial estimating article says sealcoating is most likely bid by the square foot, and the gallon count comes from the same number, so one careful trace serves both the quote and the order.

The free satellite measurement tool traces the lot from its address and Cut out removes islands and buildings from the total. In MakeHay, the saved measurement fills a per square foot line's quantity with Use in line and updates the line if the trace is edited.

Step 2: Sealcoating coverage per gallon from the data sheet

Take coverage from the data sheet of the sealer you will pour, on the line that says concentrate. SealMaster's sealcoating FAQ says coverage rates vary by product and tells you to follow the specification sheets; another brand's sheet may not match the two below.

AsphaltPro's estimator's rule is about 60 sq ft of normal pavement per gallon, up to 100 sq ft on well-maintained or new pavement. That is sealer going down, not concentrate in the drum: it sits below the TDS's 70 to 82 sq ft for mixed material. Use it to check a mixed-gallon total, never to size a concentrate order.

Step 3: Sealcoat mix ratio per 100 gallons: water, sand and additive

The mix design is published per 100 gallons of concentrate, so scale it to your gallon count and the water, sand and additive fall out.

Sand is never left out. The coal tar TDS says that in all cases sand shall be used in the mix design, SealMaster's FAQ answers "Is sand required" with yes, clean silica sand, and the "How often" FAQ gives the reason: sand provides traction and safety for vehicle and pedestrian traffic.

Step 4: Two coats, and when a third is specified

Two coats is the minimum, so the formula multiplies by two unless the job says otherwise. The MasterSeal TDS calls for a minimum of two coats and the coal tar TDS says apply two coats.

A third coat is optional and local. Both TDS pages and the sealcoating FAQ use the same wording: a third coat may be applied to high traffic areas such as entrances, exits and drive lanes. Measure those lanes as their own shape and add one coat's worth of gallons for that area only: a 6,000 sq ft drive lane at 100 sq ft per gallon adds 6,000 ÷ 100 = 60 gallons of concentrate.

Step 5: Pavement condition changes the number

Pavement condition decides where in the 100 to 120 sq ft range you land. The MasterSeal TDS says application rates may vary with pavement porosity; the coal tar TDS says coverage rates may vary with pavement age and porosity. AsphaltPro puts it in field terms: older, more oxidized pavement requires more material, and a pavement untreated for five or six years will absorb more of your product.

The examples below use 100 sq ft per gallon for a lot that is gray, open-textured or past the every 3 years interval SealMaster's FAQ calls typical, and 120 for smooth, recently sealed pavement. New asphalt waits: SealMaster's sealcoating FAQ says a minimum of 30 to 60 days, and the coal tar TDS a minimum of four weeks at 70°F. The temperature post covers the 50°F floor and the day-after check.

How much sealcoat for a parking lot: buying it by the drum or the tote

A lot's order rounds up to whole containers, and the container sets the price per gallon more than anything else. Asphalt Kingdom's sealer store, read on October 13, 2026, listed asphalt emulsion sealer by the drum, the skid, the tote and the tanker load; the four listings below are the ones a driveway or lot order lands on, and the per-gallon column is this post's division, not the store's.

The same page says a drum gives 5,500 sq ft of coverage, 100 sq ft per gallon for a single coat with a sprayer (100 sq ft per 2 gallons for a double spray), and 50 to 60 sq ft per gallon by hand. It does not say whether the product is concentrate or ready to use, so ask before adding water: a ready-to-use sealer takes the mixed coverage.

Crack filler for the same job

Crack filler is ordered by the pound from measured crack footage, not from the lot's square footage, and it goes down before the first coat. Measure the cracks in linear feet, then use the pounds per foot method in How to Price Crack Sealing Per Linear Foot to turn feet into boxes of sealant and a per linear foot line.

Putting the order on the quote

The customer's quote shows square feet and coats; the gallons, sand and water stay on your side as cost in a sealcoating price book.

In MakeHay, the sealcoating starter list carries "Sealcoat, two coats" and "Sealcoat, one coat" per square foot and "Mobilization and lot prep" as a flat price (the parking lot maintenance list carries "Sealcoat, two coats" too); reprice them under Settings › Services. On the invoice, Cost & markup on each line takes Your cost ($) and Markup (%), with the margin shown only to you, so the drum price lands there and never on the customer's copy. The suggested sealcoating weather rule is max rain 40 percent and min temp 50°F, checked the day after.