Water service upgrade for home fire sprinkler

Discussion in 'Plumbing Forum, Professional & DIY Advice' started by mattster1975, Apr 1, 2013.

  1. mattster1975

    mattster1975 New Member

    Messages:
    10
    Location:
    Texas
    Hi:

    I am looking at installing a home fire sprinkler in a 2 story slab home.

    The current water service is only 5/8" and the sprinkler contractors have advised that is not going to be big enough.

    Is it possible to replace the existing water service to and inside the the house with a 1" service, or does it make more sense to either
    1. get a separate dedicated meter for the fire sprinkler and have it enter the house above grade (with insulation)
    2. have a 1" meter installed and then have that line tied into a new sprinkler line and existing domestic water line in a valve pit (with shutoffs and backflow preventers as requires) and then have the 1" line enter the house above grade.

    (the shutoff for the sprinkler will be at the meter and inside the house locked open I believe).

    Any tips generally on retrofitting these systems is appreciated.

    thanks!
  2. jimbo

    jimbo Plumber

    Messages:
    8,997
    Location:
    San Diego
    First ask the water company about costs. You pay an meter fee based on size. But the water RATE for sprinkler system may be different, so it may pay for it to be on a separate meter
  3. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    22,313
    Location:
    New England
    Depending on the sprinkler head type, design, quantity, and their placement, 1" may not be sufficient. One condo near me made up of townhouses needed 2" service per each unit. They all complain about their water demand charge. Many utilities charge by how much water you COULD use in addition to how much you DO use.
  4. Dominick G Kasmauskas

    Dominick G Kasmauskas New Member

    Messages:
    1
    Location:
    New York
    Look into Tank and Pump options. Tank required to hold enough water for 10 minute fire flow. Generally around 300 gallon tank, not very big. Pumps can be electric or there are a couple manufacturers that have non-electric pumps that run by stored CO2 or Nitrogen cylinders or air compressor.

    May be less costly than worrying about underground, meters, backflow prevention, and ridiculous fees for fire sprinkler systems.
    Last edited: Apr 2, 2013
  5. mattster1975

    mattster1975 New Member

    Messages:
    10
    Location:
    Texas
    I am thinking about tanks too. I was leery of the tank because of the reliance on the electrical grid, but if there are non electric pumps that makes it more interesting. Mostly I want the sprinklers to give me a few more min to evacuate if there is a fire so a 10 min run time is ok.

    The other part of the project is the whole pipe install in the house. There are options about where to run the pipe - I have floor trusses so I am thinking it is best to put the pipes in the ceiling (and either cut the ceiling drywall or pull up the carpet and go in from the 2nd floor. It is possible to run the pipes along the wall ceiling junction and conceal with molding too. I'm just not sure the best way to go an the sprinkler guys either won't touch any drywall, or will just do rough demo.
  6. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    27,230
    Location:
    Cave Creek, Arizona
    There is no water flow through a sprinkler system unless there is a fire, so the majority of them are connected to the house line. In fact, some systems are being installed as part of the house plumbing system rather than having their own piping. I once asked the fire marshall why they connected the fire line AFTER the house valve, since that made it ineffective if the homeowner shut off the water for a vacation, for example. He said, "If the water is turned off, there is probably on one in the house. Our fire sprinklers are to save lives, so if no one is in the house, we don't care if it burns down."
  7. mattster1975

    mattster1975 New Member

    Messages:
    10
    Location:
    Texas
    Yes - if I was building a new house I would probably do a system like this (UpHonor makes a PEX system that works with domestic water). The only risk would be if the whole house was shut off and we were sweating in a water heater and started a fire that way (but this would be during the day anyway when fire risk is lower and it's easier to get out etc).

    Texas has a program for plumbers where they can take a continuing ed class and get certified to install residential sprinklers though I'm not sure how many folks are doing this.

    I think my current water supply is not adequate though for a fire sprinkler system (it is only 5/8" line and I am not even sure where it comes into the house).
  8. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    22,313
    Location:
    New England
    In another 10-years, sprinklers in new construction may very well be a universal thing in the USA...it's being enforced in some locales now and expect it to spread. Often, a fire only starts in one room, so you may not need a lot of water to put it out if the sensor turns it on fast enough. In some cases, seconds count. In some, it could smolder for a long time before it might generate enough heat to trip the thing. Getting proper coverage with the flow and pressure you have is critical to a full-coverage system. Expect more choices as these become mandated and the sales volume goes up in the future.
  9. mattster1975

    mattster1975 New Member

    Messages:
    10
    Location:
    Texas
    A lot of newer construction is done with light weight construction (floor and roof trusses and wood I-beams etc) and it seems that this style of construction does not perform as well in a fire when compared to traditional construction with larger dimensioned lumber. Houses built with lightweight construction have structural failure sooner in a failure making sprinklers for these kind of homes more important.
  10. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    27,230
    Location:
    Cave Creek, Arizona
    quote; The only risk would be if the whole house was shut off and we were sweating in a water heater and started a fire that way

    The way most domestic fire systems are connected, it would be shut off any time the house valve was closed, such as installing a water heater.
Similar Threads: Water service
Forum Title Date
Plumbing Forum, Professional & DIY Advice Water service fittings pack joints May 3, 2014
Plumbing Forum, Professional & DIY Advice 1 1/2 water service to home aprox 1300 ft. Mar 5, 2014
Plumbing Forum, Professional & DIY Advice Need expert help, polybutylene water service? Oct 7, 2013
Plumbing Forum, Professional & DIY Advice UPC Code question about water service sizing Sep 13, 2012
Plumbing Forum, Professional & DIY Advice Need Advice On This Water Service Entrance May 3, 2012

Share This Page