What is the best way to clean a concrete porch ,patio andf walkway with these stains?

Question

Porch is covered above but is on north side of house so it tends to get a slight green moss film in spots. Same with walkway. The patio has an oil stain from the grill and rust marks from a cast iron park bench.

I don't have time to rent a power washer but eventually will have to, just wanting to know what can be used in the meantime to give it a general cleaning and remove the spots- especially the rust. CLR tried on one of the rust spots only turned that spot whiter than when new, so not much more attractive than the rust stain. Anything you have tried that works for a great general cleaner?

Answer 1

mmmm,just some insight.

There is no magical cure for cleaning stained concrete.Once concrete is stained it's stained.The green moss (slime) as you call it is probably from constant water running over it.I would look at surrounding drainage issues.

As for the other stain issues "it is what it is".Now a passing thought of sorts.After a thorough cleaning with say a driveway cleaner/pressure washer try this.You may be able to stain it (concrete stain),neutralize the acid,let dry and seal it.You may have to use a little darker shade to help hide stains but is doable.Another consideration is the condition of existing concrete,if it's junk it's junk (tear out and replace).

No accurate answer but ideas,only you know.Or consult a reputable company in your area for advice.

My Best

Answer 2

If your concrete is old enough like of over a couple of years you can use Tide laundry soap. I works very well as a degreaser and can clean about any stain you have. Beyond getting more light to the porch and walkway I don't know what to tell you about that.

Answer 3

Cleaning concrete is very easy and you will like the result.  TSP (Tri Sodium Phosphate) will clean your concrete and it will look good as new.

You can purchase at any good paint store or at a Lowes or Home Depot.  Please read and follow all the directions.  TSP though an excellent cleaner it is an acid and mixed in high enough concentration will burn.  Wear plastic gloves and eye protection when applying.  Ask the professionals where you purchase their recommendations...  I just did a very quick Google search and found this on removing oil stains with TSP (http://homerepair.about.com/od/interiorh...

When your finished you should rinse well and apply a concrete sealer or stain.  Good Luck!

Tom A

Sr. Construction Project Manager

Albion, MI

Answer 4

For the green areas, mix about 10% bleach with water in a spray bottle. Spray it on, and rinse off after a few minutes. For the oil stain, use dishwashing liquid with a little water, you need to draw the grease back out off the concrete. I might also try the bleach on the rust area, but then it may whiten it more. I do strongly reccomend powerwashing, and once it is clean, apply a concrete sealer.  

Answer 5

You could use a general de-greaser on the grease spots and try some 409 on the rest of the surfaces.  Use the hose to wet an area down, spray with the 409, then use a big push broom as a scrub brush, then spray off the 409.