Carpet Cleaning
 

The carpet in our upstairs has never been cleaned. We never wore shoes on it over the last 10 years. It's still pretty clean, but the stairs are in need of cleaning. I realize once you clean the carpet for the first time the scotch guard goes away.
My question is what is the best process for cleaning carpet.

I've been told by people in the carpet business that once you get the carpet cleaned the 1st time, you need to have it done on a regular basis after that because the dirt and any stains will keep showing up after time...

My experience with home rental carpet cleaners is that they will make everything look great, but the carpet will start to wear quickly after they've been used.

And that's simply because of the soap residue that is left. I have a friend that does CC and he says there is always enough soap in previously cleaned carpets that he can spot and rinse and they come clean. No new soap.

126, since your carpet has no residue, I'd look into dry cleaning where they use treated towels on a rotary machine.

Goes to show you your feet aren't as clean as you think they are.

I have decent tan carpet, and had quite a bit of construction done.

I tried using the expensive "carpet protector" adhesive plastic rolls, but it didn't protect from rusty screws puncturing and staining. There were grease/rust/dirt stains everywhere with every tear.
That product was way too much money for the application and left a gummy film. Buying reusable canvas dropcloths for everything would have been cheaper and easier.

For cleanup, I rented the $25 steam cleaner rented from the big-box/supermarket.
Pull the machine against the natural lay to get down deep.

The pricey cleaner which was sold with the machine didn't seem to make too much of a difference with the heavy stains. That was good they sold a mild solution.
1). I went over everything with 1/4-1/2 recommended mixture, using hot but not superhot water(remember heat sets the stain). Cleaners can strip the fibers of the factory protectant.
2). I used the concentrated cleaner(Spotshot if necessary) on a wet rag or sometimes directly on stains.
3). I immediately went over everything with water only. Did that a couple times.

If the carpet has been cleaned before, there may be enough dried cleaner remaining to not need it. Just use water.
Plan on a full day, and slide furniture on pieces of heavy plastic fim.

When I used to clean carpets in my rentals, I had one of those Hoover carpet cleaners from Costco. I could do as good of a job or better than a commercial cleaning company. I also used it for my carpets at home. Instead of the detergent cleaner (I think that's what those are), I used Folex instead. I would use that as a cleaner in the machine and found going over the carpet at least twice afterwards with only water did a very good job. You have to watch how much water you get in the carpet. You don't want to over do it. That goes for any cleaner you use in a machine too.