To seal or not to seal (my driveway)

June 10, 2015 7:49 AM

Is it worth sealing an asphalt driveway? I can't find authoritative internet advice about this. Lots of asphalt companies, advise doing it every few years, with a variety of rationales. But they offer sealing services. Many people on various DIY-type discussion boards say it's a waste of money. Some claim sealing hastens deterioration ("asphalt needs to breathe"). Others say you have to keep water out (but, water seeps under driveways from the side, anyway). My particular details:

I have a fairly steep 100-foot driveway that was installed 18 years ago and never sealed. It is in great shape, no major cracks or potholes. This is in Vermont; it freezes, and the driveway is plowed and occasionally sanded in the winter. Annually for the last 203 years, I have filled a few small cracks that were 1/4-1/2 inch, using the goop that comes in a jug. There are a few hairline cracks I'm keeping an eye on. I don't care about the aesthetics of it; in fact I think shiny black sealed driveways are ugly. But I'd consider sealing if there is a demonstrable benefit. For example, has any impartial testing outfit done a long-term test of two identically-installed and -situated driveways, one sealed regularly and one left untreated, to see which one lasts longer? Is my crack-filling regimen enough, or would I extend the life of this driveway by sealing it every 3-4 years? And if so, with what? (I'm aware of the shady traveling contractors in this racket, no need to warn me about them.)

posted by beagle to Home & Garden (9 answers total)

If our neighborhood's driveways are any indication we should have sealed ours!
Some people here are sealers and some aren't. The sealers are all ok. Ours needs to be repaved.
(all our homes were built about same time)
posted by ReluctantViking at 8:18 AM on June 10, 2015 [2 favorites]

We just buy a bucket or two from Menards (or whatever home store you have) and seal ourselves every 3 or 4 years. If I compare it to my grandpa's driveway which, for the last 12 years has not been sealed, his driveway is going back to rubble. It is my understanding that sealing it replenishes the lost goop that holds the rocks together that is asphalt. It wears off with time and use.
posted by jillithd at 9:02 AM on June 10, 2015 [1 favorite]

Can you tell me what the name is of the goop you use? My driveway has cracks, weeds are taking root, and I'd like to repair it. The sealer fills in minute crevices, keeps water and roots out and keeps tiny crevices from becoming cracks. I don't want to use it because I like to go barefoot and it will make the driveway far too hot in summer. It does help it defrost a bit earlier in snow and ice.
posted by theora55 at 11:28 AM on June 10, 2015

As a data point, my stepdad, a retired civil engineer and Grand High Muckety-Muck of Caltrans (CA's highway agency), would just fill the cracks in his asphalt driveway for years, under the rationale that the asphalt didn't get nearly the amount of traffic a road does. However, his frame of reference is a bit… well, skewed. Driveways != freeways, sure, but it's a hassle to do cracks by hand when you have a 100-foot driveway. (And for some strange reason, the taxpayers would frown upon borrowing the necessary equipment from the nearest Caltrans equipment yard, go figure.)

After a few decades of this, he got so fed up with doing it himself that he ripped the entire driveway up and paved it with bricks on top of a foot-deep layer of aggregate, to freeway specs. That brick driveway will be here for future archaeologists to marvel over.

Everything you never wanted to know about slurry seals and how they improve roads.

Everything you never wanted to know about how to repair cracks in asphalt.
posted by culfinglin at 12:12 PM on June 10, 2015 [5 favorites]

I sealed mine last year [two years ago?] after a sealer company dropped off an ad offering a sealing from barely any more than I would pay for the materials at Menards. I think I paid $70-80. It looks better than it did before. I have far fewer weeds attempting to grow out of my driveway now.

Then the city cut a giant hole in it for some street work and after a few complaints they had it resealed by parties unknown.
posted by chazlarson at 4:03 PM on June 10, 2015

Asphalt will eventually oxidize, and the binder will no longer hold the small pieces of aggregate in the pavement matrix.

How quickly oxidation occurs depends on the initial asphalt mix design, bituemn quality and your climate.

If you got stiff broom and vigorously swept do you remove lots of little rocks out of the surface? If so, then that's sort of what happens when you drive on it, and I would be looking a doing an enrichment seal in the next couple of years. Keep up with sealing the cracks - anything that keeps water out of the pavement is a good thing.
posted by insomniax at 7:46 PM on June 10, 2015 [1 favorite]

Response by poster: Theora55, I don't know the name of my goop because the label fell off my jug, but I buy it at Ace Hardware.
posted by beagle at 6:22 AM on June 11, 2015

"It is my understanding that sealing it replenishes the lost goop that holds the rocks together that is asphalt. It wears off with time and use."

"Asphalt will eventually oxidize, and the binder will no longer hold the small pieces of aggregate in the pavement matrix."

Po-tay-to, Po-tah-to. I'm glad there are much smarter words out there for what I was trying to say. :D
posted by jillithd at 6:24 AM on June 11, 2015 [1 favorite]

Response by poster: In case anyone checks back here, that line in the original post should say "the last 2-3 years" not "the last 203 years."
posted by beagle at 11:43 AM on July 12, 2015