Concrete cleaning and sealing....does it keep it clean?

[Julian]

I've done quite a bit of searching online for the answer to this question from someone other than a concrete sealing company...but to no avail. So back to my trusty source (here) for some opinions....

I live in NC and have a long concrete driveway that sits under huge pine trees. The driveway looks great after it is power washed, but quickly gets stained again by leaves/pine needles etc. What I'm wondering is if I seal it with a concrete sealer, does this make any appreciable difference in keeping it cleaner?

I'm considering doing my own test by sealing once section of the side walk and taking photos over time....but someone has to have done this.

 

[Murf'n'surf]

It will help but requires a yearly or bi-yearly maintenance. I used to seal an exposed aggregate driveway every other year with a xylene based clear sealer. The tricky part is to apply the product without having it turn white because there was moisture in the concrete or applying too much product. After years of doing this I can tell you to pass on the sealing and put money into an overlay of pavers or a skin coat of Portland and carved to look like stone and stained to your choice of colors. Concrete polishing if done properly will last a lifetime but doesn't look good on a driveway(my taste)

 

[Bruce]

How many square feet is it?

Have you considered using one of the epoxy garage floor coatings? I believe that would resist staining.

 

[OperationROL]

Yes. It will make a noticeable difference. My walk way is sealed and now after 8 years it needs it again and I can tell. Before nothing could stain it. We use a lot of salt up here so it affects the seal over time. I imagine you would be fine for some time down there. After you seal it you may want to consider less pressure washing and on a lower setting.

 

[Murf'n'surf]

Oops. Hit post by accident.

Maybe you should look into a water based sealer because they are much easier to apply and do not turn white if too much is applied.

Cut the tree down and life will become easier in this department! Firewood!!!

 

[Julian]

The trees are on the neighbors property, and I've offered to pay half the cost....but he's tight on money, and there are probably 5 or 6 80-100' pines that would need to be eliminated, and one of them is a split top (2 heads on the tree that apparently requires 2 cranes to take down carefully) that on its own they want $3000 to take down as its over a street lamp, electric and cable boxes.....

Might be one of those jobs I'll just leave to the neighborhood teens (IE keep paying them to power wash) rather than escalate the PITA factor! LOL Having a beer on the porch sitting in 77 degrees with a light breeze ain't helping my give a shit factor either! LOL

 

[Big Shasta]

The trees are on the neighbors property, and I've offered to pay half the cost....but he's tight on money, and there are probably 5 or 6 80-100' pines that would need to be eliminated, and one of them is a split top (2 heads on the tree that apparently requires 2 cranes to take down carefully) that on its own they want $3000 to take down as its over a street lamp, electric and cable boxes.....

Might be one of those jobs I'll just leave to the neighborhood teens (IE keep paying them to power wash) rather than escalate the PITA factor! LOL Having a beer on the porch sitting in 77 degrees with a light breeze ain't helping my give a shit factor either! LOL

FYI, for the future, if the tree ever takes ill and looks like it's dying, homeowners ins should pay to have it removed.

 

[0627Devildog]

How many square feet is it?

Have you considered using one of the epoxy garage floor coatings? I believe that would resist staining.

Epoxy coating on an exterior surface exposed to the elements all year long have difficulty holding up and they are damn near impossible to do over. Especially applied to an old surface, as even after power washing you simply cannot get all the dirt out. This causes areas that do not adhere, and as a result bubbling/chipping can occur.

Stick with the sealer for outside, though it may indeed require a yearly/once every other year coating it is a much better option for existing concrete that will be exposed to the elements.

Oh and @Julian, just because this isn't about a boat, doesn't get you off the hook for pictures once you do the project. . . . . .

 

[Julian]

I did a quick cleaning of the top half yesterday, but it was too dark when I finished for a photo (well I took one and you couldn't tell the difference!). These damn pine cones leave nice marks on the concrete that won't come off with a power washer. Took me 2 hours to do 1/3 of it.....should have paid a teen! But at least it was in the 80's while I did it yesterday...only in the 60's today. I'll get some pics today.

 

[Murf'n'surf]

Go get some pool chlorine and a pump sprayer. Spray the chlorine on before pressure washing and it will pull the organic stains right out of the concrete. Down here is SW Florida we spray everything with chlorine to keep it growth free!

 

[Julian]

Go get some pool chlorine and a pump sprayer. Spray the chlorine on before pressure washing and it will pull the organic stains right out of the concrete. Down here is SW Florida we spray everything with chlorine to keep it growth free!

I gather this doesn't damage the concrete? And will it kill the grass next to the driveway?

Can used chlorine for washing clothes?

And what amount do I mix?

 

[Murf'n'surf]

It will not damage the concrete as long as you flush well. You can use regular Clorox laundry bleach also, mix 50/50.

It doesn't kill our kind of grass but your fescues are a little more sensitive so rinse with lots of water.

 

[txav8r]

Don't you love the experience and intelligence of this forum? Good input here. I concur with @0627Devildog about using epoxy coatings outside...just won't hold up well and the UV will yellow them. I have horrible luck with cleaning stains from my drive, and will look into the bleaching, as it works on so much! But what I have discovered, is that the product you have heard talked about here before, LA's Totally Awesome, will remove organic stains easily too and won't harm the grass either. I use that on our front porch all the time, as the grasshoppers leave the tobacco juice type stains that won't come off with anything else I have tried, even bleach. I also find that the power washing opens pores in the concrete and makes it easier to hold stains. I can't seem to get the walk or drive clean either without using a fine jet and that then literally takes the surface off. So using the fan nozzle does get the dirt out of it, but not the stains. What I would consider is a concrete stain, like they stain interior floors with. And you will still need a sealer over that. But power washing after applying these can lead to damage to the sealer and stain too if you use anything more than a fan pattern nozzle for sweeping. Oh, if using the Awesome, you will need to use it at least 50/50 to get it to lift and melt the heavy stains, but less for general cleaning of the drive. And some places may need full strength. Same as bleach, rinse with lots of water.

 

[Julian]

Here are the before and after shots....

 

[Murf'n'surf]

Yep. Chlorine that concrete and you'll be golden! The chlorine does the work so pressure washing will go very quick. Most of your run off looks like it will go to the street so hurting plants/grass will be minimal.

Some of those dark spots will need a nice thick layer of bleach to eat though the algea.

 

[Zeus2013]

I have this product at home that you spray one and leave it. It kills algea and moss and keeps the stains away for a season. I will need to get the name later. The 30 second chlorine spray is great. I used it once and only needed a hose to rinse it off.

 

[justason]

Hi @Julian Personally I never power wash my concrete surfaces. I have used sealer on some patio pavers I put down some time ago and it hinders the staining from Oaks and similar ok.

Pressure washing breaks down the surface integrity of the cured concrete and accelerates the wear from weathering, freeze/thaw, and leads to pitting or chunks breaking free.

Here's an article on it that goes into greater detail. Quality of concrete (porosity) is a large factor as they reference directly.

I have cleaned with various chemicals like bleach and the concrete cleaners that are sold for pressure washers. I let them sit a while and garden hose it off or push broom the cleaner around.

http://www.cement.org/for-concrete-books-learning/concrete-technology/concrete-design-production/perils-of-power-washing