Do It Yourself: Professional sealer can help with cracks

Q. Our blacktop driveway emerged from winter with a number of hairline cracks that weren’t there before. I had repaired some other cracks a year ago with some home-center crack filler (caulking-gun type), but those patches have shrunk and are loose. How can I make more permanent repairs?

A. Some of the inexpensive asphalt crack fillers sold at home centers and hardware stores don’t work very well. I have tried some of them, and have had results similar to yours – the patches would shrink or crack, often in less than a year.

The best bet is to look for commercial-grade or professional-grade crack fillers. These aren’t usually stocked in stores with the regular caulks, but with other driveway-repair materials such as sealers and cold patch. Building-supply outlets where contractors shop are another likely source.

One good prospect is Crack Stopper Rubberized Asphalt Crack Filler, which sells for about $7 for a 10-ounce caulking-gun cartridge. Some of these products are also available in larger squeeze bottles.

I also got better crack sealing results with silicone asphalt crack filler, but unfortunately I haven’t been able to find it this year.

You should read the directions for any crack filler you use. In general, hairline cracks should be cleaned before sealing. I use an old paint brush to sweep off dust and loose particles.

Squeeze a bead of sealer along the crack, then use a putty knife to press it into the gap and smooth the top. If the driveway hasn’t been sealed for a couple of years, apply a sealer after all cracks have been patched.

Q. We have a concrete patio that develops a lot of mildew. The patio gets no sun. We had it pressure washed a few years ago and the mildew came off, but it returns rapidly. What kind of surface can we apply to keep it permanently free of mildew?

A. You could try painting the patio with a patio-and-porch paint treated with a hefty dose of mildewcide additive, but there is no guarantee that it will work for long and you might have recurring maintenance problems with the paint.

In fact, I don’t know of any surface that won’t develop mildew or mold if conditions are right: lack of sun, moisture and poor ventilation.

I think your best bet is to buy an electric pressure washer. This should cost you about $200.

These washers develop about 1,500 to 1,800 psi (pounds per square inch) of pressure, which is enough to flush off mildew and dirt if the nozzle is held rather close to the surface. When you see mildew developing, pull out the washer, plug it in and hook it up to a water source, and blast it off.

Buy the washer when you see some mildew on the patio. Try it immediately, and if it doesn’t flush off the mildew, return it and buy another brand.

Pressure washers are also excellent for many other cleaning jobs, including removal of ground-in dirt from sidewalks and other hard surfaces, washing outdoor furniture and vehicles and house siding.

The washer should include a built-in GFCI (ground-fault circuit interrupter) for shock protection.

Q. We recently bought a house with five bathrooms. All the toilets are of the water-saving type, and there isn’t enough water to make any of them flush properly. A plunger is always needed. Is there anything we can do to improve the flushing without replacing the toilets?

A. All new toilets sold in the United States are of the water-saving variety, with maximum water per flush no more than 1.6 gallons. Some new toilets use even less than that.

You don’t give any details on your toilets, but many high-efficiency water-saving toilets work just fine under normal circumstances. High-efficiency toilets generally cost $200 or more.

Some toilets are also equipped with pressure-assist devices that help flushing, but these devices cannot be retrofitted on existing toilets. If this is a new house, I think you should try and get some information from the toilet installer, and ask him or her to check the flushing action.

If you were stuck with cheap, poorly designed toilets, you might want to upgrade a couple that are most used to get better performance. I have two high-efficiency American Standard toilets, bought at Lowe’s, and seldom have any flushing problem in normal use.

You might also check out toilets with a pressure-assist device such as Flushmate. You will pay more, but it should give the plunger a rest.