All About Homes Residential Inspection Service

I’m thinking of expanding our home by adding two bedrooms and a bathroom at the rear of the house. I went down to the city to ask about permits and any specific regulations that might affect the way the addition is built. I was told that if the addition is more than 50% of the size of my house, that I would have to have fire sprinklers installed. I’ve never heard of this before, and I have lived in Fremont for over 18 years. Is this a new city code? How did they get this passed without anyone hearing about it?

V.R., Fremont

In December of 1977, the City of Fremont passed Municipal Ordinances #2270, 2140 and 2141, better known as the “Sprinkler Ordinances”. These ordinances are basically the result of the devastating fire that destroyed the Country Club Apartments in 1996. The blaze which was able to quickly spread through the hallways, left hundreds of people homeless. It was one of the worst fires in Fremont’s history, and raised many questions about the safety of other buildings in the event of a similar fire.

Concerned about the safety of its citizens and its buildings, the City of Fremont determined that a specific ordinance addressing the need for sprinkler systems was not only necessary, but also in the best interest for the community. The ordinance that was passed, made changes to the 1995 California Building Codes (in force at that time), requiring that sprinkler systems be installed not only in commercial and apartment buildings, but also in new and in certain circumstances, existing residential construction.

The new Fremont ordinances required sprinkler systems in all new, residential construction with permits and plans that are applied for after January, 1998. It also affects existing structures that are added onto by more than 50%, or increased in size to more than 2500 square feet.

Once you pass either of these size limits, you will be required to provide a sprinkler system in the whole structure. This will include protection in garages, carports, bathrooms, concealed spaces, water heater closets, laundry rooms, attic spaces, and basic living areas of the house.

To determine what kind of sprinkler system you would need, it is necessary to consult with a licensed C-16 Contractor (someone who is certified to design fire sprinkler systems and install them). Based upon the size and configuration of the building, a specific design would be created, based on a two or four head calculation for water flow (the number of sprinkler heads likely to go off at the same time).

The design would consider the number of sprinkler heads needed, the size and length of the sprinkler piping, as well as the water pressure from the water district. The system should be capable of providing approximately thirteen gallons of water, per minute, from each head, plus an additional five gallons a minute demand, in case water is being used at another source (dishwasher, washing machines or landscape irrigation).

For example, lets say that you were adding a small addition to your house, and a two head sprinkler calculation was required. That means that a total water flow of 31 gallons of water a minute (13+13+5) is necessary to supply water to the sprinkler system for the structure.

To supply this volume of water, the house would have to have a minimum of a 3/4 inch diameter water meter, and a one inch diameter water supply line to the house, depending on the water pressure in the street. That’s fine for new construction, because you can install whatever size line is necessary at the time.

However, most homes built before the early 1980's were provided with only a 5/8 inch diameter water meter and a 3/4 inch feed to the house. Adding even a limited sprinkler system to these homes could require that both the main water line to the house, and the water meter, be upgraded to the proper size. Your water district can tell you how much water it can supply, and they can determine if the present meter is large enough to supply the volume necessary for a sprinkler system.

Costs for the design and installation of a sprinkler system in new construction ranges from about $1.50 to $2.00 a square foot. However, there can be additional costs for retrofitting a sprinkler system into existing construction because of the additional work of installing the piping in finished walls and ceilings.

In addition to the sprinkler system, the ordinance also requires that two audible alarm devices be installed and activate when a sprinkler head goes off. One is an exterior alarm bell installed in the front third of the building facing the street, the other is an interior alarm centrally located between sleeping rooms in the hallway. The interior alarm must be audible in all sleeping rooms with the doors closed.

How do ordinances like this get passed? First, the city has to be able to prove that because of local climatic, geological and topographical conditions, it is necessary to create an ordinance to revise the State Building Codes and require that sprinkler systems be installed in new and existing construction. This is usually based upon information from the building and fire departments.

Once the ordinance is drafted, the city must have two public hearings for community input. Notices of these hearings are usually posted in some part of the newspaper for the public to read. Once the hearings are held, if there is no strong opposition, the ordinance is approved by the city council and set into law.

You can see a copy of this ordinance on the city’s web site at www.ci.fremont.ca.us

John R. Schneider is a licensed general building contractor and a certified residential code specialist. He is president of All About Homes, a residential inspection company, and has been performing code and construction consultations since 1985. Readers may address their comments to John Schneider, 24326 Mission Blvd. Suite 7, Hayward, Ca 94544. Fax number: 510 537-8666. Please include your phone number. Schneider will answer questions of general interest in the paper. He reserves the right to edit the letter for brevity and clarity. Readers are encouraged to contact a competent contractor or code consultant for specific information regarding questions they may have about their homes.