Driveway expansion gaps, do they need to be sealed?

Old 04-22-19, 11:26 AM
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Driveway expansion gaps, do they need to be sealed?

My concrete driveway has expansion gaps that are unsealed, and tend to get filled with dirt, moss, etc. I live in the Seattle area, which sees plenty of rain, and occasional snow.
My questions are:

1) Do I actually need to seal it, or is it OK to leave alone? What "happens" other than collecting dirt?

2) Presuming I do, the best solution I've found is to use Sikaflex self-leveling w/ a backer rod. The problem is that my driveway is sloped. Should I use the self-leveling on the "almost level" gaps, and mix-and-match with non-sag sealant for the sloped lines? Or just use non-sag everywhere?

Thanks for any guidance.
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Old 04-22-19, 03:36 PM
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Here in Michigan I have sealed my joints to keep the water out which helps with freeze thaw and heaving of the slabs.

If you don't experience that cold condition then it's more cosmetic!
Old 04-22-19, 05:06 PM
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Here in NC, a little colder than you in Seattle, we don't do anything to concrete expansion joints. Dirt collects in them which eventually allows weeds to sprout but a quick shot of Roundup takes care of them.

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