Remodeling a bathroom in a sprinklered house: the 55 square foot line, steam showers, and the head over the tub

Bathrooms are the room Northern Virginia owners remodel most, and the one where the sprinkler system gets forgotten until the tile is up. A 1990s Centreville or Ashburn townhouse bath gets a frameless glass shower, a heat lamp, a bigger exhaust fan, and sometimes a steam generator, and every one of those touches a rule the sprinkler designer followed when the house was built. This article covers which bathrooms have a head and why, what a steam shower and a heat lamp do to a head that was chosen for a cool room, where the glass goes relative to the spray, and where the sprinkler work sits in a bathroom schedule so it costs a morning instead of a redo.

Why some bathrooms have a head and some do not

NFPA 13D, the standard every home sprinkler system in the region is designed to, lets the design skip a bathroom whose floor area does not exceed 55 square feet. The exemption list has the full table. A five by eight hall bath is 40 square feet and usually has no head. A primary bath with a double vanity, a soaking tub, and a separate shower is well past 55 and has one, often two. The plan for your house shows the number, and the plan finding guide covers where to get a copy if the folder from closing is empty.

The remodel problem is that the line moves. Take the wall out between a hall bath and the closet next to it, and a 40 square foot room becomes a 70 square foot room. It now needs a head, which means a change to the approved plan, which means a permit and a sprinkler contractor. The reverse is less common but it happens. Splitting a big bath into a bath and a laundry closet does not make the existing head go away. Removing a head is sprinkler work with the same permit, and the laundry closet gets its own head under the same standard.

Steam showers, heat lamps, and the head rating

A standard residential head carries an ordinary temperature rating and is meant for a room whose ceiling stays under 100 degrees. The temperature ratings article explains the color codes. A bathroom is the coolest room on the plan right up until someone adds a steam generator. Inside a sealed steam enclosure the air can run warmer than the ordinary head was chosen for, and a head that sits in warm, wet air every morning for ten years is a head we do not trust. The designer has two answers. Keep the head outside the glass where the room air is normal, or put an intermediate temperature head inside the enclosure. Which one depends on the enclosure size and the data sheet for the head, and we settle it before the rough in.

Heat lamps are the quieter version of the same problem. A ceiling heat lamp mounted a foot from a head warms it every time the switch is on. Nothing happens the first winter. What you get is a head that ages faster than the rest of the house. The fix is distance, and the head data sheet gives the number for its listing. Tell the electrician the lamp cannot go next to the head, or tell us the lamp location and we move the head on the same permit.

Glass enclosures, exhaust fans, and the spray pattern

A head throws water across the room in a pattern the listing defines, and anything solid near the ceiling cuts into it. The obstruction article covers fans and lights. In a bathroom the new obstructions are a frameless glass panel that runs to the ceiling, a boxed exhaust fan twice the size of the old one, and a soffit over the vanity that hides a new light bar. Glass to the ceiling turns the shower into its own small room, and the designer treats it as one. Either the glass stops short of the ceiling so the head covers both sides, or the shower gets a head of its own. A ten inch exhaust fan housing within a couple of feet of a pendent head blocks part of the throw, and the plan reviewer will ask for a move. These are easy calls on a sketch and expensive calls on finished tile.

Tile, niches, and the pipe in the wall

The orange CPVC feeding a bathroom head usually runs in the ceiling, but in a townhouse the main can come up through the wet wall or the chase on the party wall. A tile setter cutting a shampoo niche into that wall, or a plumber drilling for a new valve body, can hit it. The contractor hit the pipe article describes what that afternoon looks like. The prevention is one line in the contract and one walk through with the plan open. Mark the bay the pipe runs in with tape before demo and nobody cuts a niche there.

Sidewall heads deserve a note. Some bathrooms in the region were designed with a sidewall head high on a wall instead of a pendent in the ceiling. Tiling that wall to the ceiling means the head escutcheon now sits on tile, and the tile thickness changes the head depth. The sprinkler contractor needs the finished wall buildup before the head is set, the same way the concealed head cup in a ceiling needs the drywall thickness.

Where the sprinkler work sits in the schedule

Four touch points. On the design visit, before the contract, we mark the plan with any head that moves, any head that is added, and the steam or heat lamp question. During demo, the system stays live. Nothing on a bathroom job needs the water off, and a closed valve is a house with no protection for the six weeks the bath takes. After framing and before drywall, we do the sprinkler rough in, usually a morning, and the county inspects it open along with the plumbing rough. After paint, we set the finish heads and plates. The cover plates go on last, after the painter is gone, because a plate that catches paint is a plate that gets replaced. The painting rules apply to the bathroom like any other room.

The permit question comes up on every job. In Fairfax, Loudoun, Prince William, Arlington, and Alexandria a head added or moved is a change to the approved sprinkler plan and is permitted as one. The general contractor cannot fold it into the plumbing permit, and a plumber cannot do the work. The head relocation guide walks through the paperwork. An inspector who finds a moved head with no permit at the plumbing final writes it up, and the bathroom final waits on the sprinkler permit that should have been pulled at the start.

What the sprinkler part of a bathroom costs

Small, when it is planned. Moving or adding a single head is a few hours of labor plus the county permit fee, and it rides on the same open ceiling the plumber and electrician are using. The expensive version is the one where the tile is up, the glass is ordered, and the plan reviewer asks why a 70 square foot bath has no head. That job opens a finished ceiling. Pricing for anything bigger than a head or two points back to the published table, where retrofit work runs $2 to $7 per sprinklered square foot and a bathroom with the ceiling already open lands at the low end.

The lines to hand the bathroom contractor

• The house has a residential fire sprinkler system. The plan is attached and the bathroom heads are marked.
• Orange CPVC in the ceiling and in the marked wall bay is sprinkler pipe. No niche, valve, or fan housing goes in that bay.
• No glass panel to the ceiling, soffit, heat lamp, or fan housing near a head without a call to the number on the plan.
• A steam generator is a sprinkler design item. Say so before the rough in.
• Cover plates come off before paint and go on after. A painted plate or head gets replaced.
• The sprinkler control valve stays open for the whole job.