Windows in Mission are an energy code job before they are a carpentry job. The city substituted its own Table N1102.1.2 for Climate Zone 4, setting a maximum fenestration U-factor of 0.32, a maximum skylight U-factor of 0.55 and a glazed fenestration solar heat gain coefficient of 0.40. Those numbers are narrower than the published table in places, so a window selected off a general specification is worth checking against Mission's table before it is ordered. Amended Section N1101.13 requires the compliance option to be elected at permit application rather than demonstrated afterwards, and it allows a HERS index of 80 or lower as an alternative path. Amended N1102.4.1.2 sets building envelope leakage at 5 air changes per hour at 50 pascals.
What the work covers
- Measuring each opening individually rather than assuming they match
- Choosing insert or full-frame replacement based on the condition of the existing frame and sill
- Removing trim and cladding as needed to reach the rough opening on a full-frame replacement
- Sill pan flashing with end dams, sloped to drain out
- Setting, shimming and squaring so the sash operates and locks without forcing
What we find in Mission homes
- Existing single-glazed or early double-glazed units nowhere near a 0.32 U-factor.
- A product schedule that has to be checked against Mission's substituted table before anything is ordered.
- A compliance path that has to be chosen at application rather than demonstrated later.
- Openings framed in the 1950s, where the rough opening rarely matches a current stock size.
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
- No sill pan, so any water past the sealant sits on bare framing
- Sealed across the head instead of flashed behind it, which traps water in the wall
- An insert dropped into a bedroom window that quietly kills the required egress opening
Planning range
$8,000 to $30,000. A handful of standard-size insert replacements sits near the bottom. A whole-house full-frame replacement with rot repair and trim sits at the top. Plan on several days to two weeks for a typical whole-house replacement.
What moves the price on a window replacement in Mission
The specification drives a Mission window number more than the installation does. Mission's substituted Table N1102.1.2 caps fenestration U-factor at 0.32, skylight U-factor at 0.55 and glazed solar heat gain coefficient at 0.40, and the compliance option has to be elected at permit application under amended N1101.13 rather than sorted out later. That makes product selection a front-loaded decision rather than a late one. The physical variable is the openings: framed in the 1950s, they rarely match a current stock size, so whether units are ordered to size or openings are modified is the line that moves. Envelope leakage is tested against 5 air changes per hour at 50 pascals.
Permits and inspections for this work in Mission
Window and door replacement is permit work in Mission, named as such in the substituted R314.2.2, which in the same breath exempts it from the whole-dwelling alarm retrofit trigger. Applications are filed on GovBuilt and reviewed by the City's Building Official. The energy provisions are the substance of the review: Mission's substituted Table N1102.1.2 for Climate Zone 4 sets the fenestration and skylight U-factors and the glazed solar heat gain coefficient, amended N1101.13 requires the compliance option to be elected at application and permits a HERS index of 80 or lower, and amended N1102.4.1.2 sets envelope leakage at 5 air changes per hour at 50 pascals. We confirm current requirements with the department on every job.
Common questions about this work
Do replacement windows need a permit in Mission?
Frequently yes, particularly for full-frame replacement or any change to an opening. Permit requirements are confirmed with the local building department before work starts.
Will new windows pay for themselves in energy savings?
Rarely on energy alone in this climate. The honest reasons are comfort, operation, noise, maintenance and appearance, with energy as a contributor.
What is the difference between insert and full-frame?
An insert goes inside the existing frame and is less invasive, but it reduces glass area. Full-frame removes everything back to the rough opening, and it is the only way to correct a bad sill or bad flashing.
Window Installation questions from Mission homeowners
What performance do new windows have to hit in Mission?
The city substituted its own Table N1102.1.2 for Climate Zone 4: a maximum fenestration U-factor of 0.32, a maximum skylight U-factor of 0.55 and a maximum glazed fenestration solar heat gain coefficient of 0.40. A product picked off a general specification is worth checking against that table before it is ordered.
When is the compliance path decided?
At permit application. Amended Section N1101.13 requires the compliance option to be elected then rather than demonstrated afterwards, and it allows a HERS index of 80 or lower as an alternative path.
Is there an air leakage requirement?
Yes. Amended Section N1102.4.1.2 sets building envelope leakage at 5 air changes per hour at 50 pascals, verified by blower door test.
Call (913) 395-8571 or request a written estimate before any work starts.