Sealer performance F.A.Q.

Why are two thin coats better than one thick coat?

Much like paint, sealer applied in two coats dries and cures much better than one thick coat application. Remember sealers are water-based coatings, which cure through the process of water release (evaporation). A thin coat will release water much faster than a thick coat. If applied in one thick coat, sealer will have a tendency to hold water and stay soft for a longer period of time, possibly causing tracking.

Peeling problems may be caused by sealer not bonding to oil spots or any other surface contaminants like dirt, grease, etc. or oxidized pavements. All the areas should be thoroughly cleaned; oil spots shall be primed with specialty primers. Oxidized pavements should be treated with a specialized primer or a diluted coat of sealer or asphalt emulsion.

This could be due to incomplete mixing of clays and fillers in the manufacturing process of the sealer. Your sealcoating manufacturer should be contacted to rectify this problem.

This could be due to incomplete mixing of clays and fillers in the manufacturing process of the sealer. Your sealcoating manufacturer should be contacted to rectify this problem.

 

Sealcoatings based on coal tar are manufactured using refined coal tar within a very narrow range of properties. Coal tar suppliers remove most of the lighter components (potential irritants), quite effectively.

In our opinion, the ambient conditions or improper skin protection causes the skin irritation and burning sensation. On hot humid days the vapors coming out of the sealer do not dissipate fast enough and have a tendency to deposit on the skin, causing the irritation. People with lighter skin are, therefore, affected more than people with darker pigmentation. Protective clothing and equipment are a must for safe handling of sealcoatings. Wear long sleeved shirts, pants, impervious boots and gloves and use safety goggles. Use a skin barrier cream and a sun screen with a high SPF factor on face and other exposed body parts. Read the Material Safety Data Sheet (M.S.D.S.) supplied by the manufacturer.

The industry professionals association, Pavement Coatings Technology Center (PCTC) at the University of Nevada at Reno is currently researching into the components in the refined coal tar that cause skin irritation and the possibility of reducing those components, without jeopardizing the sealcoating properties.

It is usually an adhesion problem. The surface aggregates in these areas become smooth (polished) over the years of usage. For any coating, including sealcoatings, to bond properly, it is imperative that surface should by sufficiently rough. Our recommendation is to use a specialty primer to prime faster traffic lanes, exits and entrances. These primers penetrate the smooth polished aggregates and allow the sealcoating to bond effectively. In very high-traffic locations a third coat may be required on the main drive lanes to equalize wear.

Asphalt Sealer Experts

ABC Paving and Sealcoating are well known as the experts in Central Florida commercial paving. Here are some commonly asked questions on the performance of asphalt sealcoating. If you have any additional questions, please feel free to contact us.

 

Sealer performance F.A.Q.

Florida Paving Contractor

As a leading Florida paving contractor, ABC Paving and Sealcoating provides superior service and expert workmanship. How can we help you?

How soon can I sealcoat a freshly laid asphalt?
As soon as the surface rids of light oils, through oxidation. To ensure its time, spread some water on the surface. It the water spreads evenly without beading, and shows no ‘rainbows’ from surface oils you are ready. This is also called ‘water break test’. It usually takes about 1 year, depending on geographical locations.

The coverage rate dictates the film thickness which can be measured by a simple film thickness gauge, available at most paint stores. Select a 10′ x 10′ area of the pavement and place a 3″x 6″ metal plate in the center. Spray sealcoating in this area and lift the metal plate before the sealcoating dries. Use the film thickness gauge to determine the wet film thickness. The reading will be in mils (1/1000 of an inch). Compare this reading with the desired film thickness for 0.12 gallon/ sq. yard coverage which is 21 mils.

Water-based acrylic or latex traffic paints. Allow at least 24 hr. after the application of the final coat of sealer.

Mix Designs F.A.Q.

Can you explain sieve size, % retained, % passing, etc.?

Sand or the other aggregates added to sealer must fall within a set of particle sizes, neither too coarse nor too fine. This is ascertained by the sieve analysis which means that sand has been sifted through a set of screens with varying mesh sizes meaning the openings in the screen. Percent retained means how much of 100 grams of sand was retained on the screen and % passing is how much passed through the screen. Use your manufacturers recommended grades.

 

Sand is used for traction, skid resistance and also to provide a uniform texture to the surface. Sealcoatings with sand wear longer and are much safer to walk and drive on.

 

The use of latex additives is very common. There are many latex additives to impart all types of performance advantages. For example:

  • Rubberizing additives improve flexibility, durability, toughness, etc.
  • Faster drying additives help sealers dry fast.
  • Thickening additives build the viscosity of sealcoating diluted with large amounts of water.

Appearance is only part of the benefits. The sole purpose of sealcoating is to protect and preserve the asphalt. One coat will possibly provide only half of the protection and wear out in less than half the time. You will have to sealcoat more frequently if you use only one coat. This would be more costly since labor costs for cleaning and surface-prep do not change for a two-coat application.

 

Follow the manufacturers’ recommendations. Normally 25-30 gallons per 100 gallons of concentrated sealer are recommended. Higher percentages are usually recommended for mix designs that use additives and extra amounts of sand.

 

The viscosity went haywire because the additives were not compatible with each other. Do not mix different additives and stick to manufacturer recommendations. Also the manufacturers’ warranty may be void if you use other additives.

 

Those are special sand slurry specifications and not used commonly for sealcoating specifications. The industry recommends a maximum of 8 lb. of sand per gallon. Very high sand loading (18 lb. for example) will result in a coating that will be poor in flexibility, adhesion and chemical resistance.

 

Commercial Paving

With more than 30+ years experience, we use our experience and the latest equipment available to get the job done right, the first time in a timely, cost effective manner. Some of our services include: asphalt paving, asphalt repairs and prevention, pothole repairs, sealcoating, line striping and marking, thermoplastic, crack filing, signs and safety devices, concrete sidewalks, concrete curbs and site preparation.