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Before replacing your exterior tile grout, try these inexpensive methods to restore it

Look closely at the grout in between the patio tiles. It just needs a deep cleaning, not replacement. (Tim Carter)

Q: Tim, my outdoor deck is a concrete slab with gorgeous tile on it. The grout is a mess, and I believe I have to replace it. The quotes to do this work took my breath away. How does one make the determination if the grout needs to be replaced? Is there an alternative to make the grout look presentable? What would you do if it were yours?

Joan C., Santa Barbara, Calif.

A: Tile decks are very popular in places where you don’t get freezing weather. A little over a year ago I helped a friend in California do some outdoor tile restoration work. A previous owner of his home had painted his Mexican tile. It was a mess!

The only reason I'd consider doing all the work to replace tile grout is if it's crumbling and falling apart. Grout can crumble if the installer added too much water when he mixed it or he used too much water when wiping the grout to make the joints smooth.

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Almost all outdoor grout for deck tile is sanded grout. The most basic sanded grouts are a mixture of fine silica sand, Portland cement and dry pigments to give the grout color. Some grouts have other dry additives to give them more strength, but these are not needed if you install grout correctly.

Assuming the tile grout is in good shape but it looks bad, I'd perform a simple test first to see if I could get it to look like new. I'd deep clean a 3-foot by 3-foot area. There are several methods you can use.

The simplest and cheapest method is to use an oxygen bleach solution. Oxygen bleach is a powder you mix with water. It’s nontoxic. Don’t confuse this with chlorine bleach that is sold in white jugs at the grocery store! Chlorine bleach is toxic to all nearby vegetation, and it can remove the color from the grout.

You mix up the oxygen bleach solution, pour it onto the grout and tile and allow it to work on its own for 30 minutes to an hour. If the solution soaks into the grout, add more so there’s a standing layer of liquid. You’ll see countless tiny bubbles working to clean the grout. At the end of the waiting period, scrub the grout with a stiff scrub brush and rinse. Allow it to dry. It should look fantastic. If it’s not completely clean but looks much better, then do a second cleaning. The grout will look best when it dries in a few hours.

You can also pressure wash the grout, but you have to be very careful. A pressure washer, if used improperly, can damage soft Mexican tile and/or the grout. Keep the nozzle of the wand at a very low angle, about 15 degrees, to the surface of the tile and grout.

Steam cleaning is yet another method that may restore the grout. I'd try all these things before I'd consider grinding out the grout and starting over. In almost all cases grout in good shape can be cleaned and made to look like new.

Q: Tim, can you give me some advice on the best house paint to use? Every brand says their paint is the best, and it can be very confusing when trying to compare them. If I hired you to paint my house, what would you do to make the paint job last and last?

Walt D., Rockdale, Ill.

A. I distinctly remember being placed in a trance by a savvy paint salesman many years ago. He was talking about the magical ingredients in the paint, how they’d perform and why I shouldn’t go anywhere else.

It’s important to realize paint is just a form of glue that has other ingredients and properties. Think about it. You apply paint to a surface, and it’s supposed to stick to it. That’s what glues do: They stick to things.

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As you might expect, there are all sorts of different glues and adhesives when it comes to paint formulation. The least expensive ones are vinyl acetate resins. Next up the ladder is 100 percent acrylic resin or glue. I’ve had the best success with urethane resins in house paint.

Urethane is a very sticky glue. You know this if you've ever applied clear urethane to wood. It grabs onto wood fibers and most other surfaces like a cat's claws hook your sweater.

The first thing I always do before painting outside is to read the label on the paint can. I then follow the instructions to the letter. No matter what the label says, I always wash the outside of the house like I wash my truck. I use soapy water and rub the surfaces with a great brush I bought that's used to clean RVs. I then rinse the house well.

The next step is to caulk all cracks and do any repair work. If there's bare wood and the finish paint says to prime the spots, I do that. I never work in direct sunlight as that can dry the paint too fast.

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