Q: I have a small concrete patio in my back yard. The yard also features a lot of old trees, with very long and thick roots. The root system is lifting up my patio, so I have to replace it. I'd like to use another type of material, but I'm afraid I will have the same problems. Any suggestions so I can have a patio where I can still entertain?

Q: I have a small concrete patio in my back yard. The yard also features a lot of old trees, with very long and thick roots. The root system is lifting up my patio, so I have to replace it. I'd like to use another type of material, but I'm afraid I will have the same problems. Any suggestions so I can have a patio where I can still entertain?

A: I'm a huge proponent of paving-stone patios, so I suggest you consider a design that could feature a raised section. You might use a professional landscaper to add soil to the existing yard, then design the patio so the root system is well below the surface of the new patio. A multilevel patio, with some steps and raised areas, might be just the thing to protect the roots and the integrity of the patio.

On the other hand, installing a patio over the root system could be a problem in the long run. Who's to say the roots won't push up the paving stones over time? Usually, a paving-stone patio is placed on a bed of crushed gravel covered by a thin layer of sand or crushed bluestone. Some installers use a 4-inch bed of concrete on which to lay the stones. Either way, I suspect that even the paving-stone patio could be lifted or moved by the expansive root system.

Another option — and I think this might be the best solution — is designing a multilevel deck made from one of the many composite wood products. Trex, TimberTech, EverGrain and Weatherbest are among the more popular composite lumber products, and most of them feature accessories, such as railing systems. Composite lumber, made from recycled plastic and real wood fibers, resists rot, decay and insects.

, and it comes in several wood-like colors, complete with the feel and look of wood grain. And, best of all, it is a low-maintenance product. You never need to paint or stain your deck.

A raised deck made from composite lumber, designed around the root system, should give you years of service.

Q.: Do you recommend sealing the grout or ceramic tile that we're having put in our basement utility room, which has a washer, dryer, sink and furnace?

A.: Sealing the grout depends on the joint. Generally, sanded grout, which contains sand for added strength, is used on joints wider than 1/16 inch, like for larger floor tiles. Non-sanded grout is used on thinner joints, like for tiles used for walls and countertops.

A lot of contractors use a grout that contains a polymer or mix the grout with a liquid latex additive. These additives improve the grout's flexibility, which prevents cracking and separating, and it also is said to boost stain resistance.

Since this is a utility room and in the basement, I suspect it will be an area that attracts some dirt and debris, especially with your furnace in the room. So, if you have wide joints, use a sponge-type paint brush to apply any number of commercial grout sealers. Simply dip the edge of the sponge brush into the sealer, then carefully dab it into the joint. Most grout sealers should not be applied to the tile itself, so work slowly.

On thinner joints, I don't think sealing is going to make a difference. It's such a small joint, that any dirt or debris that is trapped should be easy enough to clean.

As for sealing the tile itself, the rule of thumb is that a glazed tile — one with any type of shiny surface — does not need sealing. If you have an unglazed tile, then refer to the manufacturer's recommendations. Many unglazed tiles need not be sealed, so lean on the advice of the manufacturer. To be sure, test the tile with a little water. If water dropped onto the surface of the tile is absorbed, it's a good sign the tile needs to be sealed. Just a tip: I would not use an unglazed tile in a high-traffic area like a utility room. Pick a tile that is glazed but not overly shiny; less sheen usually translates to better traction and reduces the chances of slipping if the tile gets wet.

Distributed by the Los Angeles Times-Washington Post News Service