Mr. Sprinkles — Installing The Fire Sprinkler System

One of the major upgrades I wanted to do with this remodel was to install a residential fire sprinkler system. The reason that I did this was (a) it was required by new codes for new construction and large remodels (not strictly applicable to my situation), but more importantly it (b) increased survival rate in a fire by 90% and reduced damage by 70%.  How could I not do this?

I posted the details of the design of the system in a previous blog (link here), but now it was time to actually do the work.

Putting in a residential fire sprinkler system is within the ability of an advanced DIYer. If you can install a PVC irrigation system, and have some plumbing wherewithal, then you can do this. HOWEVER, the installation requirements are a bit complicated, so unless you develop your own plans, or really understand the requirements and codes, then maybe this is something you leave to the pros. Bottom line: if you have good plans and understand them, and you’ve done some work with PVC pipe, then you’re probably GTG.

Naturally, the start of the project means that I had to get the supplies. The plans called for some specialized material, but fortunately because California has required these systems in new construction since 2013, it was not too difficult to find suppliers, both locally and online. I found a local distributor, and I got most of the supplies from them. Unfortunately, they did not carry the brand of sprinkler heads called out in the design, and the plans are required to show the sprinkler patterns and installation requirements, which are specific to a given brand, which means I had to buy that specific brand or re-do the plans. So I had to mail order the sprinkler heads. Thank God for the Internet and online shopping!


All my sprinkler parts ready for action! This is just as much fun as opening up a brand new Heathkit. If you don’t know what that means, then nevermind…. *(See note at bottom of post)

Sprinkler Set

A sprinkler system needs to have a spare sprinkler set. I saw this in code somewhere, so I got it, but I think I may have been reading the wrong part of the code. In hindsight, I’m not totally sure if this applies to residential sprinklers (NFPA 13D), but I wanted to make sure I passed inspection.

I think that the most challenging part of this project was figuring out how to run the supply lines. Because the flowrate of the water is carefully calculated to ensure proper function of each sprinkler, you can’t just run the piping anywhere you want. Each fitting counts, and elbows in particular cause a loss of flowrate. The hydraulic calculations in the plans account for these, but you can’t go over the total number for any given branch. And the plans don’t show all of the lumber you have to maneuver around, so it’s a bit of a puzzle. But, like any puzzle, I just broke it down into steps and figured it out one section at a time, and eventually got to the end.

Getting the lines through the lumber takes some doing. The first thing you need is a drill and drill bits that can handle the job.


Heavy duty drill and drill bits. Although a lot of pros use the spade bits, I found that when drilling 1-1/2″ holes resulted in a lot of broken bits. I had a ship auger, which is (a) really expensive and (b) best suited for keeping a hole straight when boring through very thick wood. But I found a better option…..

Drill 2

The drill bit on top is a self feed bit from Milwaukee. It is much cheaper and easier to handle than the ship’s auger, and it makes cutting through studs and joist a breeze.

Here is a link for a good package of wood boring drill bits.

The next thing is to plan where the lines will go. You want to drill through as little wood as possible while still keeping the lines straight with the minimum amount of bends (i.e., elbows).

Garage 1

View of the main 1st floor header with branch lines for the garage sprinklers.

Ideally you want to run the lines behind the ceiling, but I had to run one line through the studs in a wall. Because the supply line is 1″, the holes in the studs were greater than allowed for strength purposes. Fortunately, Simpson Strong-Tie makes a reinforcement called a “stud shoe” which restores the strength of the studs.

Holes 1

First hole drilled for the master bedroom sprinkler branch. I have marked the locations of the rest of the holes on the studs so the pipe is nice and straight.

Holes 2

Holes for the sprinkler pipe branch all drilled and lined up nicely. Drilling makes a lot of mess, so I was cleaning up a lot.

Bend To Fit

In order to get the pipe to fit through the line of holes, I had to flex the pipe to get it into the first hole.

Stud Shoes

Stud shoes reinforce oversize holes cut for the 1″ pipe.

Getting the sprinklers at the right height can be a little tricky. You have about 1/2″ of variance, but that can be used up quickly if you’re not careful about measuring and cutting the pipe.

Cutting the pipes is not a big deal because they’re plastic, but making sure that they fit properly into the fittings and are glued properly is pretty important. First, you have to de-burr both the inside and outside circumferences of the pipe cut so it fits easily into the bottom of the fitting. The glue is also important. Not too much, or it will run into the fitting and clog it; not to little or it won’t bond properly and you’ll have a leak. You need to use a specified glue with this pipe, and it’s a different color so the inspector can check whether or not you’re doing a good job of joining the pipes.

Securing the pipes is also very important. The installation instructions will specify the spacing of the hangers, and that’s based on the flexibility of the pipe you’re using. The reason these are critical is because when the sprinkler goes off, the outrush of water will act like a jet, subjecting the sprinkler to an upward motion. If there’s too much motion, then the sprinkler head disappears into the ceiling and doesn’t do a good job of putting out the fire.


The mounting strap has to be within 9 ” of the head to prevent vertical backlash when the sprinkler head activates.

One thing that I had to do was install some copper lines. the reason was that the plastic lines cannot be painted, and they cannot be installed outside. Since I had an instance of each, I constructed these portions of the headers as shown:

Living Room 2

If you look up from my living room, you’ll see the sprinkler heads mounted on the beam. I could not use PVC pipe because (a) it is not rated for exposed installation under sloped ceilings and (b) cannot be painted. My planned decor did not include the “industrial” look of exposed orange piping.

Finally, it was time to test. Since the code prohibits a shutoff valve between the street supply and the fire sprinkler header, I wanted to do a pressure test before I made the final connection. I hooked up a garden hose to the test fitting in the riser and, lo and behold, I had leaks! Hey, I knew I probably would have at least one problem, so that’s why I provided for an easy way to back out of the testing without causing a long and inconvenient pause in the water supply to the house that was occupied at the time. Turns out that I had “forgot” to glue a couple of joints. Missing that is easier than you’d otherwise think because the procedure to fit pipes together is to dry fit first so you don’t have to cut out and replace when you have to (inevitably) adjust something down the line. Still, I could have done a more thorough job with my pre-test inspection.

Test Setup

Connection to hose bibb for first testing.

I did not glue the ends of this tee before I tested for the first time. It’s pretty easy to check for glue lines, but I happened to miss these because I was going too fast.

I also had a leak on some of the sweated copper piping. The cause of that was trying to re-use a small length of pipe that I had to forcibly remove, which deformed it slightly, and then trying to tighten down on the sprinkler head too much, which ended up cracking the already weak joint. Two wrongs do not make a right!

So, I pressure tested again, and let it set for a day. I then found a couple of small weeps at sprinkler heads, which I fixed by tightening them a bit. Finally, it was time to hook up the main water supply and test the alarm. I tried to do the connection first with unions, but that did not work very well, so I tried something called “Shark Bite”, which is a short length of pipe with compression fittings on each end, and teeth to “bite” into the underlying pipe to secure it in place. The reviews were very positive, and sure enough, it worked great.

SharkBite fitting. This is a moveable fitting that can go over a pipe to join two ends without solder. It has a very good performance history and is easy to install, but is expensive, so maybe not a substitute for more “traditional” methods when joining pipe.

Now for the test of the fire alarm. This video is of the final acceptance test.

With all of the rough work done upstairs, it was time to start drywalling!

*Note: When I was an adolescent, my dad introduced me to ham radio and bought me a radio transceiver (transmitter/receiver) in a kit for Christmas. The manufacturer was “Heathkit” and they made a bunch of inexpensive electronic kits that performed pretty well and satisfied the urge of the DIY’er to build something. I built the radio (model number HW-16) and got my Novice ham radio operator’s license. Since I was only a novice, I was restricted to CW (continuous wave) communications only, meaning that I had to use morse code. But, hey, the requirement to get your license was to know morse code (you had to pass a test), so it was all good. Plus, I got my “own” radio station callsign (WN8OFD). That was all well and good, but the most exciting thing about the whole deal was opening up the box of the kit to start assembly! Here is a link that shows what my setup looked like.

And here is what I “said” when I wanted to strike up a conversation with a fellow radio operator:

dah-dit-dah-dit; dah-dah-dit-dah (CQ)

dah-dit; dit (DE)

dit-dah-dah; dah-dit; dah-dah-dah-dit-dit; dah-dah-dah; dit-dit-dah-dit; dah-dit-dit (WN8OFD)

dah-dit-dah (K)



Roughing It

Now that the wall framing was up, it was time to start installing everything that goes inside the framing. That means electrical and plumbing lines, and in my case, data cables and fire sprinkler piping. In this entry, I’ll briefly address the rough electrical, plumbing, and data lines, as I will have a separate entry on the sprinkler system (because it’s unique and cool).

Rough service work begins with locating where you want to put stuff. For plumbing, that’s usually spelled out in the plans, e.g., where you want the sink, shower, and toilet, so that part is pretty easy, and the relevant dimensions of where the plumbing fixtures connect are standardized. However, there are some nuances that must be considered, and since I’m doing an entirely custom installation, I decided to get all of my fixtures up front. That way (a) I could look at the installation instructions and actually do measurements if I needed to, and (b) the fixtures all matched. It cost  quite a bit up front, but at least that expense is taken care of (!). So, I went ahead and marked where I wanted the toilet, sink, and shower drains and water supplies to go. Now, I had to learn plumbing.

Supplies 1

All fixtures and parts for the bathrooms, plus the toilet and sink for the MBR bathroom.

Supplies 2

The rest of the parts for the bathrooms. I also bought all of the tile at once to make sure I had it from the same run. Lots of stuff to warehouse!

As a chemical engineer and as an engineer on a nuclear sub, I figured I could deal with the technical aspects of a residential plumbing job. I had to review the relevant codes to make sure I was in compliance, but then I figured, how hard can this be? I was about to find out….

I decided to start with the toilet drain because it was the largest pipe and I found out I would have to be doing some tricky routing through the joists, which I had previously tripled to shore up the master bedroom floor structure. These extra thick joists turned out be be troublesome because the pipe had to be angled to get the slope correct and the hole saw that I was using was only slightly larger than the OD of the pipe. I eventually hammered it in but getting that last joint together was a bitch! I hope it doesn’t leak.

Toilet Drain

Toilet drain piping. See the tripled joists surrounding the pipe? I had to drill big holes through those and ram the piping in!

The next challenge was putting together the water supply system for the showers. I decided to ramp up the quality of the showers by installing a “smart” shower system that uses an electronic control in the shower to remotely control the mixing valve. I went with copper pipe because that’s what the house had to begin with, and I sure got some good experience in sweating the pipes together (turns out that it’s not that hard). The best advice that I got was to use MAPP gas instead of propane. The higher temperature of the flame makes the solder flow much better. Nevertheless, It’s a complex setup and I ended up gouging one of the press-fit O-rings when I inserted the pipe into the mixing valve, so it caused a bit of a mess when I turned on the water to pressure test.

Shower Mixing Valves Annotated

Diagram of the remote shower mixing valves. These are located in the garage directly below the bathrooms. The hot and cold water supplies connect to the mixing valves and the remote controller sets the temperature and volume through the controller signal lines. The water then goes directly to the shower head(s).

Remote Shower Control

Remote shower controller. This is all electronic and has a memory for 4 different settings (his/hers/morning/after workout/whatever).


I also found some cool water supply valves that were recessed into the wall and had a very clean look. They are called “stop pull boxes” and are made by a company called “LSP”. If you’re interested, here is their website: LSP Pull Stop Box

And some pictures:

Recessed Water Supply Valve 1

Recessed water supply valve. The valve is the brass fitting in the middle. If you look closely, you can see the ball valve itself (the silver thing in the middle). This is really slick because it’s behind the drywall and the valve is operated by a pushrod attached to the threaded rod on the left-hand side. Looks very clean after installation which I thought was important for a pedestal sink.

Recessed Water Supply 2

Recessed valve installed. The eustachon will cover the hole OK. The brand is “LSP” and the device is called a “pull stop box”.

Going on to rough in the electrical, the plans are important, but I decided I wanted to do some Human Factor Engineering to get the exact location of the switches and lighting fixtures. I imagined myself doing everyday tasks like going to the bathroom, going to the shower, getting dressed, getting ready for bed, etc., and that helped me locate switches so that (a) they would be easy and intuitive to reach for and (b) I could operate the lights from different locations to minimize going back and forth when I wanted to turn something on or off. I also put in extra wall receptacle boxes, especially near where the bed and home office would be. Receptacle and switch boxes are pretty easy to install, so with that done, I was ready to start running wires.

Rough Electrical Bedroom

Example of the customization that one can do if you’re doing this yourself. I added the data and power boxes for the flat screen TV at the last minute (at no cost to the customer).

Running the wires for the rough electrical is something that’s not typically in the plans, which only show the locations of the receptacles, switches, and fixtures. I guess I could have done a schematic diagram, but I figured I would only be doing this once, and as long as I was disciplined in labeling each wire, I would be OK. To run the wires, I did have to plan out where I would be bringing in power from the electrical panel, and then how that power would be distributed throughout the room. The bedroom has two circuits: one for the sink in the bathroom, which needs to be a dedicated GFCI circuit per code, and one for the receptacles and lights. The “current” electrical codes (pardon the pun) require that receptacles in living spaces (bedrooms, living rooms, dens, dining rooms) be AFCI protected, so I needed to take that into account as well. The dedicated GFCI circuit was pretty easy (one wire from the panel to the receptacle), but the other wiring was more involved. The first thing that I did was to bring in power to a receptacle box, and then distribute power to the other receptacle boxes from there. The lighting circuits then tapped off the receptacle boxes.

One thing to keep in mind is the number of wires you have running in and out of each box, and the number of “devices” (switches, receptacles, both of which are referred to as “yolks” in the trade). There is a limit based on the heat load, and there’s a fancy calculation in the NEC, which it turns out, is not trivial. Here is a link to an good explanation. To make things a little easier, I just always get the biggest box possible for the number of devices I want (switches/receptacles) and have not run into any problems.

Electrical Switches and Receptacles

Good example of tailoring the electrical controls beyond the minimum. I can control both lights outside the garage (front and side) and the garage work lights from this location. The front garage door light can also be controlled from the master bedroom and the front door because it is a security and safety feature. I’ve also installed smart switches, where necessary, to allow control automatically under given conditions (e.g., coming home at night, opening the garage door, fire alarm or smoke detector goes off to illuminate egress routes). The receptacles with built-in USB chargers are a must, pretty much in every room.

Routing the wire takes a little planning. The main idea is to drill as few holes as possible, which typically results in running the wires in the ceiling. The other “trick” is to unroll the wire so that it’s flat. If you just pull the wire from the roll, then it will come out twisted and be difficult to staple neatly to the framing. Unrolling it before you pull the wire takes some effort: you have to pick up this heavy roll and heave it ’round several times. But it pays off with a neat and professional installation.

After the wiring was installed, I needed to energize some circuits so we could continue to live normally (if you call living in a house during a remodel “normal” — I guess it’s the “new normal” for us). Despite my supreme confidence in my ability to install some relatively simple electrical work, I flipped on one of the breakers and there was a loud “pop” (“arcing and sparking” in the trade).

Electrical Boo Boo 2

I thought I smelled something funny. Better find out what happened here!

Turns out that I tightened down the cable clamp too tightly and the clamp cut through the insulation and caused a short.

Electrical Boo Boo 1

Forensic analysis showed that I had tightened down the strain relief so much that it cut through the insulation and caused a short. More is not necessarily better!

I felt pretty bad and embarrassed about that, but later, after doing some additional reading in my electrical “how to” books, I found that these sort of things occasionally happen even for the pros. I guess that’s one way to get experience! At any rate, I had to pull the entire cable and replace it because you’re not allowed to splice or patch an electrical cable. All interconnections must be in electrical boxes that have an opening through the drywall to prevent an electrical short from causing a fire behind the drywall.

Lastly is the data cabling. For my project, I’m running a minimum of 2 cat6e ethernet cables and one RG-6 cable per room, but the the master bedroom and home office, I ran quite a few more. I started with standard electrical boxes, but found that low voltage boxes are easier to work with, so from now on, I’m using those. Because these cables are circular in cross section, there’s no need to be too fussy with the unrolling. However, the installation should still be neat. I found some nice cable organizers that allowed me to create nice data cable runs, which was important as the cabling multiplied as I approached the wiring closet.

Data Lines Annotated

Data cables running through the attic. With a minimum of 2 Ethernet and one coax cable per room, that added up pretty quickly. I put a lot of these in the master bedroom because I wanted the cables for a flat screen TV and a home office.

Wiring Closet

Wiring closet replaces the furnace, which was relocated to the attic. All data cabling from the upstairs is run and neatly bundled (on the right). The loose stuff is the cabling from the living room and garage, which needs to be bundled later when I run the rest of the downstairs cabling.

Finally, I had to install draft stops. The inspector pointed this out to me, so that was something I was unaware of, but once I figured it out, it was pretty easy. Basically, wherever you have a penetration through the sole or top plates of your framing, you need to seal the openings. The best way is to use polyurethane foam that comes in a can. You can get a one-use can with an applicator, but I found that hard to control, so I ponied up for a pro applicator, Worked much better, and I figured I’d be using it for other things.

Draft Stop

Draft stop for the data lines coming into the wiring closet. I also had to accommodate the gas line going up to the furnace, which is now in the attic.

So with the rough work done, it was time to put in one of the true infrastructure “upgrades” that I planned for this remodel: a residential fire sprinkler system. Stay tuned…..