Updated: Oct 14, 2022
While new concrete driveways are commonly used in just over a week for parking regular vehicles, avoid driving over the edges as they are still weak at that point. It is best to wait one month before driving or parking on it. While the greatest change in strength occurs within a month, your driveway concrete will continue to harden over the next few years. The floated finish or in pressure washers’ terms, “the cream” is most vulnerable during the same period. Happy Window Cleaning won’t pressure wash concrete for at least two years after a new installation.
Those who’ve worked with concrete understand that there is variation in the durability and aesthetics of finished concrete. The basic ingredients in most driveway pour are cement, aggregate, and water. The durability of your concrete depends on having the correct ratio, good aggregate (not too much sand), and the weather conditions when the pour occurred. Rain for example, if allowed to work its way into the mix will weaken concrete overall. Recording the installation process can serve as valuable evidence later on.
Pressure washing concrete will remove organic stains and discoloration from many kinds of soils. Some stains however will require additional chemical treatments and are not included in the cost of a standard cleaning. Rust, tannin, and oil-based stains (seen above) are the most common types encountered. Generally, anything that is a manmade stain requiring additional steps or chemical treatments will cost a bit extra. Since tannin stains come from trees and are naturally occurring, this type of stain is included in the standard cleaning cost. By contrast, rust stains from air conditioning or patio furniture are manmade problems. Knowing the source of the stain informs the restoration procedure. Treatments applied to the concrete such as finish and/or color additives can affect cleaning and restoration efforts. Any information you as the homeowner can record and file about those materials will inform maintenance.
Finally, in states like Michigan, avoid using rock salt over the first two winter seasons. We have seen brand new driveways ruined because some contractors fail to inform homeowners of these basics. Rock salt will remove the cream and expose the aggregate leaving ugly blotches on your formerly beautiful concrete driveway. If you have a slope on your driveway, and you are worried about slipping and falling on the way to your mailbox each day, sprinkle sand rather than rock salt and only cover the designated path you walk on. Avoid driving over the sand if possible. Driving the car over the sand is a form of mechanical agitation that can also harm the fresh cream on your new driveway surface. It is the same result mentioned above that can happen from physical agitation with pressurized water when applied too early in the hardening process. It is fine (during the warm months of course) to spray the driveway with a low-pressure garden hose nozzle.