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Learn How To Sealcoat Asphalt With Our Sealcoating Asphalt How-To Guide

Before you get started with this guide, we want to let those of you who found this page from the internet know that we also offer the products and equipment to help you sealcoat a driveway or parking lot. We sell to both Professional Sealcoaters as well as DIY Home Owners, Small Business owners, Property Maintenance, Municipalities, Runway Authorities etc. Feel free to shop around, but you will probably find that we already have some of the best prices around on the internet.

Our guide is very in-depth on how to sealcoat a driveway, parking lot or any asphalt surface. It will walk you through how to sealcoat whether you are new to the business or a home owner looking for ideas on how to do it yourself. There really isn't much to it but keep in mind that a few steps are very important to the whole process like proper preparation. Sit and read the guide or print it off for later, we don't mind either.


1.0 Sealcoating Introduction
1.1 Benefits of Sealcoating
1.2 Conditions Conducive to Long Lasting Sealcoats
2.0 Materials Used in Sealcoating
2.1 Refined Coal Tar Emulsion
2.2 Asphalt Emulsion Sealcoatings
2.3 Always remember that sealcoatings will not:
2.4 What sealcoating will do:
3.0 Asphalt Pavement Preparation & Application
3.1 Your Sealcoating performance depends
3.2 Insure the following to allow maximum performance
3.3 Asphalt Pavement
3.4 Cleaning of the Pavement
3.5 Crack Filling & Repairs
3.6 Filling the Cracks
3.7 The Different Types of Cracks and Their Causes
3.8 Patching Damaged Asphalt Sections
3.9 Oil Spots; Priming & Other Treatments
4.0 Mixing the Sealer for Your Sealcoating Jobs
4.1 Water
4.2 Aggregates (Sand / Slag)
4.3 Additives
5.0 Sealcoating
5.1 General
5.2 Weather Conditions
5.3 Coverage rate
5.4 Drying Time
5.5 Equipment
5.6 Step-by-Step Summary
5.7 Tips
6.0 Bidding
6.1 Considerations
6.2 Measuring the area
6.3 Helpfdl Measuring Hints
6.4 Some Usefdl Measurements to Help You Along
7.0 Striping
7.1 Striping Specs
7.2 Things you need for your Striping Operation
7.3 Preparation


Image: Before Sealcoat
Before Sealcoat Application
Image: After Sealcoat
After Sealcoat Application

Sealcoating is a true "Barrier coat" between asphalt surfaces and destructive elements. The term "sealcoating" means keeping the redeeming properties of asphalt sealed in to prolong the pavement's life and preserve its functional properties.

1.1 Benefits of Sealcoating

The primary reason to sealcoat asphalt pavement is to protect the pavement from the deteriorating effects of sun and water. When asphalt pavement is exposed to sun, wind and water, the asphalt hardens or oxidizes. This causes the pavement to become more brittle. As a result, the pavement will crack because it is unable to bend and flex when exposed to traffic and temperature changes. A sealcoat combats this situation by providing a waterproof membrane which not only slows down the oxidation process but also helps the pavement to shed water, preventing it from entering the base material.

A secondary benefit of seal coating is an increase in the surface friction it provides. This is accomplished by the additional texture the cover aggregate adds to the pavement. With time, traffic begins to wear the fine material from an asphalt pavement surface. This result in a condition referred to as raveling. When enough of the fine material is worn off the pavement surface, traffic is driving mostly on the coarse aggregate. As these aggregate particles begin to become smooth and polished, the roadway may become slippery, making it difficult to stop quickly. A sealcoat increases the pavement texture and increases the surface friction properties.

1.2 Conditions Conducive to Long-Lasting Sealcoats

Sealcoats are affected greatly by weather conditions, especially during construction. The ideal conditions are a warm, sunny day with low humidity. Humidity and cool weather will delay the curing time and cause the seal coat to
be tender for a longer period of time making it more susceptible to damage by traffic. Rain can cause major problems when sealcoating. If the asphalt binder has not cured, it can become diluted and rise above the top of the cover
aggregate. After the water evaporates, asphalt may cover the entire surface causing tires to pick up aggregate or track the binder across the surface. Seal coating should never be done when showers are threatening. Asphalt to be seal-coated should also be in relatively good condition. This means that there should be little if any, load-related distress such as alligator cracking, rutting, and potholes. If these conditions exist, the driveway should not be sealed unless it is repaired first.

In summary, seal coating is a good maintenance technique for pavements with the following:

  • Low to moderate block cracking.
  • Low to moderate raveling.
  • Low to moderate transverse and longitudinal cracking.
  • A smooth surface with low friction numbers.


2.1 Refined Coal Tar Emulsion

The most commonly used sealcoatings are based on refined coal tar. Coal tar is made up of very stable chemicals that are closed ring-Aromatic compounds. They are not affected by the destructive elements of weather.

2.2 Asphalt Emulsion Sealcoatings

Asphalt emulsion-based coatings have gained considerable acceptance because of its ease of application and lower odor and less skin irritation than coal tar sealers. Although asphalt emulsion-based coatings do not have resistance to
gasoline, oils, fats, etc., they work very well in maintaining the surface integrity of asphalt pavements and keep cracks from appearing.

2.3 Always remember that sealcoating will not:

Compensate for pavement defects. They are intended as a protective coat; not as crack filler or leveling material. Sealer is only as good as the asphalt pavement to which it is applied. Prevent the cracking of bituminous pavements, which are caused by excessive voids, poor mix stability, insufficient compaction, poor drainage, or low-use areas.

2.4 What sealcoating will do:

If you want to apply asphalt sealer to your pavement, it's important that the pavement is in good condition to start with. This means it should have been built with the right designs and materials that are suitable for the climate and usage, and constructed over a well-drained base.

If the pavement has any cracks or unevenness, and you apply asphalt sealer on top of it, the sealer can actually make those imperfections more noticeable. This is because the sealer makes the surface smoother and more uniform, which contrasts with the rougher texture of the damaged pavement.

That's why it's important to fix any existing cracks or damage before applying the sealer. By doing so, the sealer can provide the protection it's meant to, and help extend the life of your pavement.


3.1 Your Sealcoating performance depends on the following:

  • How is the asphalt pavement condition?
  • What is the preparation needed?
  • What kind of application is needed? (Coverage rates, number of coats)
  • What are your curing conditions? (Ambient & surface temperatures, humidity upcoming weather conditions)

3.2 Insure the following to allow maximum performance:

3.2.1 Asphalt Pavement: Make sure it is in good condition and suitable

3.2.2 Cleaning of the Pavement can be done with any of the following: Brushes, brooms, & sweepers Mechanical cleaners High-pressure cleaner

3.2.3 Crack Filling & Repairs: Done with the proper preparation for the type of cracks

3.2.4 Patching Damaged Asphalt Sections Pot Holes Alligator areas Soft areas

3.2.5 Oil Spots; Priming & Other Treatments

3.3 Asphalt Pavement

3.3.1 New Asphalt: You should sealcoat your asphalt as soon as it begins to turn grey or 90 days after installation. The new pavement should be allowed to cure a minimum of 90 days at 70 + ° F. The length of time for curing of asphalt pavement will vary according to the mixes used and the compaction of the asphalt.
3.3.2 Older Asphalt: Older, highly oxidized pavement with a powdery surface may have to be primed to insure the seal coating adhesion.

3.4 Cleaning of the Pavement

3.4.1 Clear Weeds: Use a weed eater or pull all weeds that are on the edge or growing up in the driveway.

Image: Cleaning Pavement

3.4.2 Remove Loose Asphalt: Dislodge loose material from the edges of small potholes and large cracks. Use a wire or you can blast out loose material with water from a hose nozzle or with compressed air.

Image: Cleaning Street

3.4.3 Scrub Area: For the best adhesion of crack filler or compound and driveway sealer/filler, scrub the entire driveway with a diluted driveway cleaner to remove all dirt and oil film. Pay particular attention to areas to be filled or patched. This can also be achieved with a power washer.

3.5 Crack Filling & Repairs

Image: Filled Asphalt Cracks

3.5.1 Cold pour crack fillers are fluid at ambient conditions, therefore, do not need heating prior to application. They are generally based on asphalt emulsions (water dispersion), containing fillers and rubberizing additives. Hot pour crack fillers are solid and have to be melted to a fluid consistency prior to application.

3.6 Filling the Cracks

Image: Filling Asphalt Cracks

3.6.1 You should fill any cracks in a blacktop drive to keep water from getting under the slab and causing more serious problems. Cracks that are 1/2" and wider, are filled with asphalt cold patch generally sold in bags or buckets. Narrow cracks are treated with a crack-filler, which are available in buckets, cans or plastic pour bottles.
3.6.2 Use a masonry chisel, wire brush, or similar tool to dig away chunks of loose and broken material from the crack.
3.6.3 Sweep out the crack with a stiff-bristled broom. Your shop vacuum will also work well.
3.6.4 Use a garden hose with a pressure nozzle to clean off all dust. If the area is badly soiled or covered with oil or grease drippings, scrub it with a strong commercial driveway cleaning agent. For a patch to adhere, the crack must be free of all such things. After using a cleaner, rinse the area with water.
3.6.5 For a deep crack, fill it to within 1/4" of the top with a closed-cell plastic backer rod or sand before applying a patching compound.
3.6.6 Apply the crack-filler according to manufactures specs.

3.7 The Different Types of Cracks and Their Causes

3.7.1 Cracks Caused by Shrinkage

Image: Crack Shrinkage

Cracks due to shrinkage are temperature related and result from the inability of the pavement to handle the stresses caused by temperature variations. As pavement becomes older and stiff, shrinkage cracking becomes worse.

3.7.2 Reflective Cracks

Image: Reflective Asphalt Cracks

Reflective cracks occur in pavement overlays that were placed over unprepared pavements in poor conditions. As the joints open they induce tension on the bottom of the asphalt overlay. Left unsealed, the crack will allow moisture into the aggregate and result in premature failure

3.7.3 Alligator or Fatigue Cracks

Image: Alligator Asphalt

Alligator or fatigue cracks are a series of interconnecting cracks in the asphalt surface forming a pattern that resembles an alligator's hide or chicken wire. The cracks indicate fatigue failure of the surface layer generally caused by repeated traffic loadings.

3.7.4 Edge Cracks

Image: Asphalt Edge Crack

Edge cracks are caused by insufficient shoulder support, poor drainage, or frost action. These cracks usually start as hairlines or vary narrow then widen and erode with age.

3.8 Patching Damaged Asphalt Sections

Image: Asphalt Pothole

3.8.1 For potholes, first dig out any loose material and dirt down to a solid base. It's best to undercut the edges slightly to provide a "key" for the patching material. Make sure the edges of the asphalt around the hole are firm.

Image: Pothole Cleaning

3.8.2 Clean all dust and debris from the hole and surrounding areas.

Image: Pothole Filling

3.8.3 If the hole is very deep, fill it to within 4" of the top with gravel. Tamp this down firmly.
3.8.4 You can work with a black-top crack filler hot-mix patch or use asphalt crack filling cold-mix patching products which do an excellent job of repairing driveways.
3.8.5 You can prime the repair area by painting it with emulsified asphalt liquid. Priming helps the new material bond to the old. Then apply the cold-patch material, patting it down occasionally with a shovel or trowel to help compact it and prevent air pockets from forming.

Image: Shoveling Pothole Patch

3.8.6 Put in a 2" depth of crack filling cold-patch and tamp it firmly or roll it with a garden roller. Add more material in 2" lifts, tamping each lift. The next-to-last lift should fill the hole to within an inch of the top. Tamp.

Image: Tamping Pothole Patch

3.8.7 Now add more patching material, filling the hole and mounding it slightly above the surrounding surface. Tamp it down as firmly as you can.
3.8.8 Fill in any low areas with more blacktop crack filler cold-patch mix. Compact it until it's even with the driveway surface.
3.8.9 Allow the repaired area to cure for 12 to 36 hours before driving on it.

3.9 Oil Spots; Priming & Other Treatments

Image: Asphalt Oil Damage

The oil and grease spots must be cleaned and scraped to remove as much of this material as possible. These spots should then be treated with an oil spot primer and allowed to dry. Acrylic emulsion-based primer that bonds tightly
with oil-spotted asphalt surfaces and stops them from coming through seal coatings.


Refined coal tar-based sealers, are supplied as concentrates (undiluted). Before application, they must be mixed with water, aggregates such as silica sand or metal slag, and additives (as needed) for proper application consistency and properties.

4.1 Water

  • Water is added to give proper fluidity to the mix
  • Clean, potable
  • Free of suspended solids and metal contaminants
  • Between 7-8 pH

Too little water and the mix will be too heavy and will not spread evenly. The excessive sealcoat will be a waste of material and may also cause tracking under hot conditions.

Too much water and the mix will be too thin and thin cured film will cause the sealer to wear out prematurely. As a result, performance will suffer.

4.2 Aggregates (Sand / Slag)

4.2.1 Sand vs Slag Sliica, which is generally referred to as sand, is exactly what it sounds like. A medium to light coarse silica rock that can be added to sealer as an abrasive additive. It's a low-cost method to create a low-slip surface. Slag is a byproduct during the refining process of metals such as iron or copper. We sell copper slag that is a great alternative to sand with some added benefits but comes with a higher cost. Sand and slag can be sprinkled on right after application or for a more uniform look, added to the sealer before application.
4.2.2 Appearance with sand/slag:
  • Uniform Texture
  • Reduced Sun Glare
  • No Streaking
4.2.3 Sand or slag hide minor surface defects
4.2.4 Sand or slag improves traction and creates a better skid-resistant surface
4.2.5 Sand or slag improves wear-ability but never claim that the sealcoating, even with aggregate, will stop slipperiness.

4.3 Additives

Additives are rubber latex-based products, which are added to the sealer to boost its performance or to impart a special property.

Some of the benefits of latex rubberizing additives:

4.3.1 Excellent sand suspension in the mix, even with higher sand loadings
4.3.2 Excellent sand distribution in cured sealer for an evenly textured surface appearance
4.3.3 Jobs will last longer
4.3.4 Faster drying of the sealer, sun or shade
4.3.5 Greater oil and gas resistance
4.3.6 Darker uniform color
4.3.7 Enables sealer to bond better to the pavement


Use Coats Seal Gallon Water Gallon Sand 100 lbs Latex Gallon Application Mix Gal/Sq. Yd
Low Traffic 1st 100 30-50 3-5 0-4 0.10-0.15
  2nd 100 25-45 0-4 0-4 0.08-0.12
Moderate Traffic 1st 100 40-60 3-5 2-5 0.10-0.15
  2nd 100 40-60 0-4 2-5 0.08-0.12
High Traffic 1st 100 30-60 3-5 2-5 0.10-0.15
  2nd 100 30-60 3-5 2-5 0.10-0.15
  3rd 100 25-55 0-4 2-5 0.08-0.12


The following is intended to give you a general account of coal tar-based seal coatings and their application. Follow your manufactures recommendations.

5.1 General

Two coats allow the sealer to penetrate the newly formed aggregates for a deep coating. However, once the driveway has been sealed, this deep penetration is no longer necessary as long as you have a good maintenance program.

Check out this video, showing how easy it is to spray asphalt sealcoating!

5.2 Weather Conditions

5.2.1 Sealer should not be applied unless pavement temperature is at least 50F° (10C°) and the air temperature is 50F° (10C°) and rising.
5.2.2 Sealer should not be applied during rainy or wet weather, or when rain is anticipated within eight hours after application is completed.
5.2.3 Sealer should not be applied to hot surfaces under the summer sun (over 90F°, ambient) without first cooling the surface with clean water. Water should dampen the surface without leaving puddles.
5.2.4 Since an emulsion may be damaged by freezing, it should be protected at all times when the temperature drops below 40F° (4C°).

5.3 Coverage rate

  • First Coat - 0.10-0.12 gallon of undiluted sealer/sq. yard
  • Second Coat-0.06-0.08 gallon of undiluted sealer/sq. yard
  • 45-50 sq. feet per gallon of undiluted sealer

5.4 Drying Time

The final coat must be allowed to dry a minimum of eight hours of good daylight drying conditions before opening to traffic, and initially cure enough to drive over without damage to the sealcoat.

If marginal weather conditions exist during this eight-hour drying time, additional time will be required. In some cases, this could exceed 24 hours.

Check the surface after this for traffic-ability before opening it to vehicle traffic.

5.5 Equipment

Use application equipment that is capable of applying the required coating rates evenly over the entire width of the application mechanism to provide a uniformly coated surface. To insure this, equip all spray units with a pumping
distribution. Equip all squeegee/brush units with squeegees/brushes that are properly adjusted and in a condition so that the application of seal coat materials is without streaks.

Use of hand squeegee or brush application is to be restricted to places not accessible to the mechanized equipment or to accommodate neat trim work at curbs, etc. Material that is applied by hand is to meet the same standards as that applied by a machine.

5.6 Step-by-Step Summary

5.6.1 Check weather forecast.
5.6.2 Barricade the driveway.
5.6.3 Do the general cleaning of the pavement.
5.6.4 Oil spot prime all oil spots.
5.6.5 Prepare to sealcoat. (According to the manufactures recommendations)
5.6.6 Sealcoat the pavement.
5.6.7 Check for spots missed.
5.6.8 Make sure the barricades are in place, and pick up all tools.
5.6.9 Next day remove barricades.
5.6.10 Stripe with water-based traffic paints, after the final coat of the sealer has cured for at least 24 hrs.

5.7 Tips

5.7.1 Keep the relative humidity in mind when determining the amount of water that should be added to the mix. RULE: If humidity is high, add less water.
5.7.2 Longer passes with the applicator will make a better-finished appearance.
5.7.3 Keep sealer off concrete surfaces.
5.7.4 Between coats, put away unnecessary tools and always keep applicators clean.
5.7.5 Complete work orders promptly and keep account of material application rate.
5.7.6 Workers should know their job and be able to speak knowledgeably about what is being done.
5.7.7 Keep all equipment on the clean pavement once you start the application.
5.7.8 Never run any vehicles over partially dried material.

Please see more information regarding Coal Tar environmental issues and hazards Here


Inspect the project, making notes of the asphalt conditions, cracks, and patching. Will you need special treatments such as oil spot primer, etc. Figure your costing to get to the final bid price (your costs + profits). A bid proposal should include all the details of what you're proposing to do.

Seal coat sealing with one or two coats.
Crack filling what you charge a linear foot and which crack fill you're using.
When you can start and/or when you will finish.

6.1 Considerations

Bid pricing will cover some small repairs and all cleaning and preparation of the pavement prior to the application of two coats of coal tar emulsion sealer.
Some considerations in your pricing are as follows:

  • Very dirty pavement - will increase the labor cost of cleaning.
  • Extensive structural cracks - will increase the cost to clean and fill prior to sealing.
  • Pavement repairs - can greatly affect the cost of the job.
  • Coarse pavement surface - will result in higher material usage and increase the cost.
  • Irregular pavement shape - will increase labor cost on the job.
  • Manual application - will increase labor costs.
  • Doing jobs in sections - lowers efficiency and increases labor costs.
  • Travel time - long trips to a job will increase labor costs.
  • Extensive curb work - increases labor costs.
  • Multi-color work - increases labor costs.
  • Time of season - slow drying time can hold up application and increase labor costs.
  • Inexperienced crew - increases labor costs.

6.2 Measuring the area

6.2.1 Squares and rectangles: one side (a) * connecting side (b) = area (a * b)

Image: Area Square

6.2.2 Circles: 1/2 of diameter (a) * 1/4 of diameter (d) * 3.1430 = area

Image: Area Circle

6.2.3 Triangles: (with a right 90-degree angle) - side forming 90-degree angle (a) * connecting side (b) that forms 90-degree angle divided by two (2) = area (a * b)/2

Image: Area Right Angle Triangle

6.2.4 Triangles: (with no right 90-degree angle) - longest side, (a) times altitude (Perpendicular line drawn from the longest side to opposing angle), (a * b)\2 divided by two (2) = area

Image: Area Non-Right Angle Triangle

6.3 Helpful Measuring Hints

6.3.1 Determine which shape the area is before beginning measuring.
6.3.2 Always measure in straight lines.
6.3.3 For curved drive measure length from the center line.
6.3.4 Never take a second measurement especially if you have any doubt.
6.3.5 Draw a diagram on your estimate for later reference purposes.

6.4 Some Useful Measurements to Help You Along

  • 1 Gallon of water weighs 8.33 lbs.
  • 1 Gallon = 4 Quarts = 8 Pints
  • 1 Square yard = 9 Square Foot
  • Square Foot/Gallon = 9 * square yard/gallon
  • Mil Thickness = 1/1000 of an inch = .0001 inch
  • Wet film Thickness (mils) = 1604/Sq. Ft. covered by one gallon of a coating.
  • Dry film Thickness (mils) = Wet film thickness (mils) * % Solids by Volume
  • Wet film thickness = 1604 / 50 = 32 mils
  • Dry Film Thickness = 32 x 40% solids content = 12.9 mils

For the proper perspective of mil thickness, a sheet of paper is 4 mils. That means two coats of sealer fully cured will be a bit thicker than 3 sheets of paper.

Material needed for a given area for two (2) coats:

  • Total square feet divided by 50 = gallons needed Total
  • Square yards divided by 5.5 = gallons needed

Bid price for the job:

  • Total square feet x unit cost per foot = Total cost
  • Total square yards x unit cost per yard = Total cost


Image: Line Striping Machine

There's one thing for sure. You can take a perfect paving or sealcoating project (which may be 98% of the project's value) and completely ruin the appearance of the whole job in the last 2% with a sloppy striping job. Straight, crisp clean lines and stencils are a must. Calking of all lines on a new layout job will insure straightness.

7.1 Striping Specs

7.1.1 When laying out parking stalls use at least ten (10) feet wide stalls if possible. (Narrower stalls can result in nicked car doors)
7.1.2 Laying out a parking lot properly should result in a good flowing traffic pattern and more parking places.
7.1.3 If there are bad oil spots on the lot, there may be adhesion problems with the new marking where they cross oil spots unless the pavement in these areas are patched.
7.1.4 Striping can be done approximately 3 hours after the sealer is dry to the touch. Time may vary depending on temperature.
7.1.5 The striper applies paint at the approximate rate of 300 lineal feet per gallon.
7.1.6 All lines will be approximately 4 inches wide. They should be straight and uniform.
7.1.7 Paint drying time will vary from 15 minutes to 3 hours.
7.1.8 Nothing brightens up a parking lot roadway more than fresh paint on stripes, pavement markings, and curbs.

7.2 Things you need for your Striping Operation

7.2.1 Striping machine
7.2.2 Small truck or trailer for transport (which you already have with your seal coating unit)
7.2.3 Stencils
7.2.4 Paint
7.2.5 Tape measure, chalk line, nails, hammer, paintbrush, etc.

7.3 Preparation

7.3.1 Layout markings using guidelines, templates, and forms Stencils and templates shall be professionally made to industry standards. "Freehand" painting should never be allowed.
7.3.2 Thoroughly clean surfaces free of dirt, sand, gravel, oil, and other foreign matter.
7.3.3 Protect adjacent curbs, walks, fences, and other items from receiving paint.
7.3.4 Verify that the new pavement coatings will be given a minimum of 24 hours to cure with no traffic.

View a list of our striping equipment.