Mission rewrote the alarm section of the residential code and it lands squarely on bathroom work. Section 500.043 omits IRC R314.2.2 and Section 500.044 substitutes a Mission version: any alteration, repair or addition requiring a permit triggers a full upgrade of the dwelling unit to new-construction smoke and carbon monoxide alarms. Not the bathroom, the dwelling unit. The same amendment set adds R314.8, requiring a hard-wired heat detector in an attached or integral garage. There is an explicit written exception, but it covers exterior-only work such as roofing, siding, windows, doors, porches and decks, and a bathroom remodel is none of those. So in Mission a permitted bathroom brings the whole house's alarm coverage up to current standard, and that belongs on the estimate at the start rather than at the final inspection.
What the work covers
- Demolition to the studs and subfloor wherever the existing waterproofing is suspect
- Supply and drain rework, including moving the toilet flange or shower drain if the layout changes
- Shower pan and wall waterproofing as one bonded system, not a patchwork of products
- Backing and blocking for grab bars, benches, glass and wall-hung fixtures
- Exhaust ventilation ducted to the exterior, never into an attic or soffit
What we find in Mission homes
- A gas furnace, gas water heater or attached garage, any of which brings the whole-dwelling alarm upgrade into the permit.
- Existing alarm coverage installed to whatever standard applied when the house was built in the 1950s.
- Cast iron waste on a drain layout designed around a single original bathroom.
- A room whose finished dimensions were set by a 1950s floor plan rather than by the fixture layout the homeowner wants.
Working in Mission, KS
Mission is a small inner-ring suburb whose housing numbers need reading carefully. About 58 percent of the housing was built between 1950 and 1959, roughly 14 percent in the 1940s and another 11 percent in the 1960s, and only around 156 homes have gone up since 1970. The citywide median year built of 1973 sits later than the single-family stock actually is, because apartment construction in the 1970s and 1980s pulls the median forward: only 2,480 of about 5,600 units are single-family detached and the city as a whole is renter-majority. Permits are issued by the Community Development Department at 6090 Woodson Street and filed through GovBuilt, and the city's own Building Official does every plan review and every inspection rather than contracting the work out to Johnson County. Residential work is reviewed under the 2018 International Residential Code as adopted at Municipal Code Section 500.040, with the 2017 National Electrical Code. MrImproveIt carries the Johnson County Class C residential contractor licence that Section 505.040(C) requires before a permit issues.
How this job goes wrong
- Waterproofing treated as a product instead of a system, so the pan, curb and wall planes are never actually tied together
- An exhaust fan venting into the attic, which relocates the moisture problem rather than solving it
- Tile set on a floor that was never flattened, which telegraphs lippage across large-format tile
Planning range
$14,000 to $45,000. A tub-in-place refresh sits near the bottom. A gut to the studs with moved plumbing, custom glass and large-format tile sits at the top or past it. Plan on two to five weeks of active work once materials are on site.
What moves the price on a bathroom remodel in Mission
Two things move a Mission bathroom number that would not move it a mile away. The first is the alarm upgrade: because the city's substituted R314.2.2 brings the entire dwelling unit up to new-construction smoke and carbon monoxide alarm standard whenever permitted work occurs, the scope reaches rooms nobody is remodeling, and an attached garage adds the R314.8 heat detector. It is a modest line and it is quoted from the start. The second is the plumbing, because the single-family stock here is 1950s and the waste layout was designed around the one bathroom the house was built with. Whether the work stays local or runs back toward the stack is the largest single variable.
Permits and inspections for this work in Mission
Bathroom work is permitted by the Community Development Department at 6090 Woodson Street and filed through GovBuilt. Mission issues both Multiple Trade and Single Trade permits, and inspections are requested through the portal at least 48 hours ahead. Review runs against the 2018 IRC as adopted at Section 500.040 with the 2017 NEC. The amendment that most often adds scope on this job is the substituted R314.2.2, which requires the dwelling unit to be brought to new-construction smoke and carbon monoxide alarm standard whenever permitted alteration, repair or addition work occurs, with added R314.8 requiring a hard-wired heat detector in an attached garage. We confirm current requirements with the department on every job rather than working from the last one.
Common questions about this work
Does a bathroom remodel in Mission need a permit?
Usually yes, as soon as plumbing, electrical or framing changes. Permit requirements are confirmed with the local building department before work starts.
Can the bathroom stay usable during the work?
Not that bathroom. If it is the only full bath in the house, that changes the schedule, and it is worth saying so before the estimate is written.
How long is the bathroom out of service?
Plan on two to five weeks of active work once materials are on site. Tile and glass are the long poles, because glass is measured only after tile is set.
Bathroom Remodeling questions from Mission homeowners
Why does a bathroom remodel mean alarms in the whole house?
Because Mission replaced the standard code section. Section 500.043 omits IRC R314.2.2 and the city's substituted version requires any permitted alteration, repair or addition to bring the dwelling unit up to new-construction smoke and carbon monoxide alarm standard. The written exception covers exterior-only work such as roofing, siding, windows, doors, porches and decks, and a bathroom is none of those.
What is the garage heat detector requirement?
Mission added Section R314.8, which requires a hard-wired heat detector in an attached or integral garage. It comes into the job alongside the alarm upgrade whenever permitted interior work occurs.
How much notice do inspections need?
At least 48 hours, requested through the GovBuilt portal. That is longer than several neighbouring cities require, so it is built into the schedule rather than discovered during it.
Call (913) 395-8571 or request a written estimate before any work starts.