Sprinklers on Roof Offer Home Protection : Fires: For greater safety in brush fires, a sprinkler system can be fashioned from plastic pipe and a garden hose.

“I grabbed my garden hose and climbed up on the roof. Pretty soon I was completely surrounded by fire. My T-shirt caught fire and I turned the hose on myself to put it out.”

These are the words of 60-year-old Gerry Hon, a retired truck driver describing his successful effort to save his house during the huge Santa Barbara fire last June.

“I thought I could save it,” he said, “they wanted me to leave but I refused to go because there is a lifetime of mementos in there. . . .”

Hon was lucky. Despite his flammable wood roof, he was able to keep his home from burning during the Santa Barbara inferno.

Fire statistics indicate that during almost all the major brush fires of the last 30 years, some people have done exactly as Hon did and saved their wood-roofed homes using nothing more than a garden hose, while neighboring houses went up in flames.

While the preferred roof material on houses in brush fire areas is one that is non-combustible, not everyone can afford to spend thousands to replace their wood roof.

For those people, installing rooftop sprinklers is a far less dangerous and more effective alternative to fighting a fire with a garden hose, or simply doing nothing.

Although local fire officials are reluctant to recommend sprinklers because they do not work in all wind conditions and there is not always an adequate water supply, many of them do concede off the record that sprinklers have helped save lots of homes during fires.

Installing the sprinklers is a do-it-yourself job that is actually a lot easier than most people would imagine.

With a little planning, the typical house can be sprinklered in an afternoon or less using relatively inexpensive half-inch PUC plastic pipe with impulse sprinklers (“Rain Bird,” “Lawn Genie,” “Toro,” “Champion,” etc.). And the whole job can be completed without having to turn off the water main.

Before starting, check with your local Building and Safety Department about permit requirements. In some cities, a permit is needed.

Of course, this job requires some common-sense safety rules about using a ladder and working on a roof:

1--Look at the slope of the roof. If it looks too steep to safely walk on, it probably is, and you should not attempt this project.

2--Check the ladder. All the rungs should be securely attached to the side rails, the rails should be free of cracks and the “feet” should be in good condition to avoid slippage.

3--If using an extension ladder, place it on a firm, flat spot where it is to be used before raising the extension. The bottom of the ladder should be set one-quarter of the ladder’s length from the base of the house.

4--The ladder should extend at least two feet above the edge of the roof.

5--Before climbing the ladder, check your shoes. You need non-slip, preferably rubber sole shoes.

6--Keep your hips between the rails when reaching out from the ladder. Keep one hand on the ladder at all times, and the other free for work.

7--When on the roof, walk carefully to avoid damaging shingles and to reduce the risk of slipping.

8--To re-mount the ladder, grab the upper portion of either rail and place your foot in the center of the rung just below the roof edge. Facing the roof, grab the other rail and swing your body onto the ladder.

9--Stay off the roof in windy or inclement weather.

With those precautions in mind, it’s time to get started. Begin by finding a hose bib with normal water pressure on the side or rear of the house to supply the roof water.

Make a trip up the ladder to measure the length of the ridge, or high point, of the roof. If you have a flat roof, measure its long axis.

Also measure the distance from the hose bib to the roof edge and from the roof edge to the ridge. This total distance tells you roughly how much one-half-inch PUC pipe (schedule 40) to purchase. Add 10% to be safe.

The pipe will be placed just below the ridge toward the back of the house so they are not seen from the front of the house.

Along with the pipe, you need to buy elbows, couplings and T-fittings.

Elbows are fittings that allow you to join pipes at 90 or 45 degrees. Couplings allow you to join straight pieces of pipe, and T-fittings are placed in the system wherever the sprinklers will be located.

To determine how many impulse sprinklers you need, bear in mind that each one will spray a circle roughly 40 feet in diameter.

Calculate the number needed by imagining a series of 40 foot diameter circles across the roof, overlapping each other about 15 feet. What is the minimum number of circles needed to cover the whole roof?

The answer to this gives you the number and approximate placement of each sprinkler. The average home needs three or four. A diagram is often helpful.

Next come the fittings. When you know the number and position of each sprinkler, imagine straight lines (which represent the pipe) between all of them and over the edge of the roof down to the hose bib.

The number of elbows needed is found by counting how many 45 and 90 degree angles are needed to connect the lines.

The number of couplings necessary is found by calculating how many straight pipe runs over 10 feet in length are needed. Pipes are sold in 10 foot lengths and must be joined by couplings.

Buy several extra elbows and couplings in case your count is off a little.

The quantity of T-fittings needed is determined by the number of sprinklers in the system. All sprinklers except the last one in the line are threaded into a T-fitting with a one-half-inch internally threaded center outlet.

Several more items are needed from the building supply store:

1--A small can of PUC primer and PUC cement.

2--Enough half-inch pipe straps to secure the pipe at eight-foot intervals. Also, a box of one-inch galvanized nails to secure the straps.

3--A tube of silicone sealant to cover the nails.

4--A metal “Y” valve for a hose bib. This device threads onto a hose bib to provide two threaded outlets.

5--An adapter to connect male hose thread to half-inch internal pipe threads.

6--A PUC coupling and elbow with half-inch internal pipe threads on one side.

7--A back-flow preventer for a hose bib.

8--A hacksaw.

Now for the fun part . . . assembling the system. Place all the pipes and supplies on the roof, and at the end point of the system you will cement the elbow with internal threads on one side to a section of PUC pipe.

First coat the end of the pipe and the inside of the elbow (the non-threaded side) with the PUC primer. It will dry within seconds.

Next coat the same surface with PUC cement and quickly attach the elbow to the pipe, making sure that the pipe end seats down fully into the elbow.

Position the pipe about a foot below the ridge, with the threaded outlet of the elbow pointed straight up. Lay the pipe out so it is aimed toward the next sprinkler and secure it with a pipe strap near the elbow.

Attach a coupling to the end of the pipe section, using the same method you followed to attach the elbow, and connect a second pipe section to it. Secure this second pipe section with another strap roughly eight feet from the first strap.

Continue adding sections until you reach the predetermined location of the second sprinkler. Cut the pipe with the hacksaw if necessary so it ends at the sprinkler location. Attach and cement a T-fitting and secure it with a strap so that the threaded outlet points straight up.

Continue adding pipe sections, couplings, T-fittings, straps and elbows where needed to make turns until you have brought the pipe over the edge of the roof and down the wall to a point just past the hose bib.

In some instances, you can run the pipe through a one-inch hole drilled in the roof above the eave directly above the hose bib. Seal around the pipe with a generous amount of silicone sealant.

Now comes the actual water supply connection. First attach the “Y” valve to the hose bib (make sure the washer is lodged inside it) and tighten it securely by hand so that one of the two outlets is either parallel or perpendicular to the wall.

On that outlet, attach the back-flow preventer and the “hose thread to pipe thread” adapter, making sure washers are in place. Tighten them securely by hand.

Now thread the PUC coupling with the threads on one side onto the half-inch male threads projecting from the adapter. Tighten with pliers.

Measure and cut small sections of pipe sufficient to connect the pipe from the roof with the hose bib fittings and “dry fit” them with couplings and elbows as needed.

Once you have this final connection properly arranged, cement all the pieces together.

Back on the roof, screw all the sprinklers into the threaded ends of the T-fittings and the last elbow, and remove the adjustment rings from the neck of the sprinklers so they spray a full circle (see sprinkler’s instructions).

Also, cover all the nail heads with a thick layer of silicone sealant to prevent roof leakage.

At last, the water show. Turn the “Y” valve control to “on” and gradually open the hose bib valve.

The sprinklers will begin to shoot pulses of water in circular patterns across the roof. Adjust each sprinkler according to the instructions to obtain the coarsest spray possible. This reduces the chance of a fine stream of water being blown by the wind.

Now adjust the hose bib valve to the point where you have the best roof coverage.

That’s it. Stand back and watch the waterworks you have created!

To use the regular garden hose, simply turn the “Y” valve control to the sprinklers to “off” and turn the other one “on.” Attach the hose to the other male nipple and use the hose bib valve as you normally would to control the water.

The final step is to inform each family member on how to use the sprinklers in an emergency. I often suggest posting instructions on the wall near the hose bib.

Be sure to inspect and test the system at least three times annually.

If you have a swimming pool, you may want to consider connecting the roof system to a gasoline powered pump that draws water from the pool. Historically, there have been some water pressure problems during brush fires and a pool pump would assure an adequate water supply.

The pumps are often available through fire protection, building supply or pool supply companies, or through catalogue sales of major department stores.

They can be set up with a “quick connect” fitting to allow instant connection to the sprinkler system. Consult your plumber.