Avoid Problems and Extend The Natural Life of Your Investment

Posted  by Steve Keddy on May 2, 2019

After so many years of dealing with asphalt cracks that you can never permanently fix, dips and divots that have developed over time and just the general deterioration of your driveway you finally bit the bullet and had everything repaved. Your new driveway is installed and it looks great! So now what! Can you forget about it? It should last and provide many years of satisfactory use your thinking. The sales rep assured me it will. Well maybe and maybe not! As with any reactive material asphalt left unmaintained begins to deteriorate from the day it is laid. That is, right from exactly day one, However, you can and will extend its life well into the future by observing a few simple maintenance tips.

Most driveway are paved with HL3 fine (hot load asphalt, max 13mm stone) which is an asphalt mix designed especially for residential driveways. This type of mix has more sand, fewer large stones and more asphalt binder giving it a cleaner smoother finish. But aesthetics is not the only reason. With more tar in the mix a single lamination ( referred to as a single lift) is meant to be more flexible and so is capable of expansion and contraction to a greater degree before failing. Whereas single lift road grade asphalt pads where shown to be more susceptible to early cracking and compression failure especially over a week subgrade and also deteriorate faster than multi lift structures it became necessary to develop a mix that would stand up better over time under restricted use. These new mixes have been in use on residential driveways for a few decades now and have load characteristics that both out perform and under perform driveways made with road grade asphalt in a number of different areas. 

Driveway Mix Behavior 

All asphalt needs regular maintenance. After 10 years an unattended asphalt pad made of HL3 fine containing more asphalt content than road grade asphalts is susceptible to losing its sand and smaller stone concentration faster under UV and oxidation effects.  When the binder material at the top surface deteriorates enough it will dry out and erode first leaving nothing to hold the sand in place. Smaller size stones will go next and finally larger stones leading to rough and dry pitting at the surface. The regular application of an oil based asphalt sealer would go a long way to mitigating these processes over  time.

Oxidation and UV penetration depths are of the order of 1 to 3 mm and result in oil degradation at its surface which in turn will lead to fine particle loss. A light coat of bitumen based liquid asphalt sealer should be applied before the first winter or in its 2ndyear at the latest to help keep surface tar concentrations at optimum levels. This will bind in the sand and also keep the finish of your driveway looking fresh and new. Asphalt sealers should never be applied too heavy. You should be able to see the original fine particle distribution as it was the day it was laid. In fact, if its done right you wont be able to tell the difference between just laid and just sealed, but you have to start early before the sand erosion starts. Now oil and water don't mix so it is not advisable to use any water based sealer on asphalt in its first 2 years. Allow new asphalt to fully harden 2  years or more. This is because you still have lots of tar in the surface and water based sealers applied early will separate the tar from the water  from the sand from the stone and you will destroy its strength and 100% drive on it and you'll scar it 100%. Preferably you will stick with professional asphalt sealing in its early years. Do this annually and follow up with regular liquid asphalt sealcoating every two years thereafter.

Finished driveway

Traffic and Loads in the First Year

Now because asphalt is rich in oil when they draw in heat on hot humid days they tend to lose tensile strength. New driveways on hot summer days will be soft but as long as you keep the following three points in mind you can get through this period unscathed:

1) No undistributed point pressure loads from ladders, bike and motorcycle stands, planters and any other undistributed type loads. If you need to place something on the driveway use a small square of plywood too distribute the load and thus avoid denting and compression failure.
2) Hose down your new driveway regularly on hot days to draw out the heat on freshly laid asphalt.
3) Avoid grinding your tires while the vehicle is stationary. Rolling turns only will avoid scaring the surface until the asphalt is fully cured.

Asphalt cures very slowly. It will not harden to a rock hard surface like concrete in a short time and when taking in heat expands and becomes flexible. It may take more than a year to cure to the point you can disregard early life carefulness

Winter With Your New Driveway 

Winters with heavy snow accumulation and susceptible to freeze and thaw cycles should pose no problems with a new driveway. However if you have ice accumulation from downspouts, frozen drain water or crushed snow avoid chopping down on the ice and instead slide shovels and ice chippers along the surface to remove it. This will avoid chipping the surface and scaring your driveway.

Salt is ok but avoid heavy accumulation for extended periods. Apply just enough to do the job. Once the driveway is cleared let sunshine do the rest and you will have a clean smooth driveway all winter,

Keep your driveway looking fresh every year by simply rejuvenating its surface oils with oil based asphalt sealers

That pretty mush sums up the basics of driveway care. If you follow these simple maintenance points and be wary of how early life asphalt can be undermined your driveway is well on its way to staying in top  condition for years to come.

Layout and text by Steve Keddy Photographs by A1 Tophat Blackcoat Corp..