Fort Bend's 2010s Housing Wave and the Cost of a First AC Replacement

A whole decade of houses, all aging at once

According to the Census Bureau's 2020–2024 American Community Survey (table B25034), 30.3% of Fort Bend County's housing stock — 92,607 units — was built between 2010 and 2019. That's the single largest slice of the county's homes, bigger than any other decade on the chart. The median year built countywide is 2005, and 61.4% of all housing here went up after 2000. This isn't a county with a handful of older neighborhoods slowly wearing out. It's a county where enormous subdivisions in Richmond, Rosenberg, Fulshear, and the Katy area went up in two- and three-year building booms, and the AC systems that came with them are aging on the same clock.

The industry's own life-expectancy figures (NAHB, 2007) put residential AC equipment at 10 to 15 years under normal conditions. Fort Bend runtime isn't normal conditions — long cooling seasons and high humidity push equipment harder than the national average assumes. Do the arithmetic on a house closed in, say, 2013, and first replacement lands right about now. Multiply that by tens of thousands of houses built within a few years of each other on the same streets, and you get whole sections where nothing failed for a decade and then three or four units go out in the same July.

What actually drives the cost of a first replacement

There's no single number that applies across a subdivision, even one built in the same two-year window, because the original installation wasn't identical everywhere. Builder-grade systems are typically sized once per floor plan and installed the same way regardless of which lot faces west, and the details that get value-engineered out — single-stage compressors, PSC blower motors, one central return serving a two-story house — all affect what a proper replacement needs to correct, not just match. Our page on builder-grade systems and first replacement goes through that list in more detail.

Cost drivers worth asking about before you compare quotes:

• Whether the replacement is sized to the house or just matched to the old tonnage
• Whether ductwork needs repair or rerouting as part of the job, not just a box swap
• Access — attic-set equipment in a two-story house costs more labor than a slab-level closet unit
• Whether a second return or additional supply runs are needed to fix an upstairs/downstairs imbalance
• Refrigerant type and line-set condition, especially on the earliest houses in this cohort

The one document that tells you if the number is honest

Because so much of this cohort sits in unincorporated Fort Bend County, there was no mechanical permit and no inspection on the original install — and there won't be one checking the replacement either, unless your city requires it. That means a Manual J load calculation, the ANSI/ACCA standard referenced by the IRC and IECC, is the only real external check on whether a quote is sized to your house. A legitimate one shows your address, not a generic model, and separate sensible and latent numbers — not a single figure rounded up to the next ton. Our system sizing and load calculations page explains what to expect from one. Asking for a copy with the quote is a fair, specific question, and one a serious contractor answers without hesitation.

A short sequence for getting through this cycle

1. Get the age and tonnage of your current system confirmed before calling anyone — the data plate on the outdoor unit has both.
2. Ask each contractor for a written load calculation with the quote, not just a verbal assurance that "we did the math."
3. Compare what's included beyond the equipment: duct repair, additional returns, and any electrical work the new unit needs.
4. Check whether the contractor is registered where required — Missouri City requires annual mechanical contractor registration, for example, separate from state licensing — since that's a second, checkable credential.
5. If you're getting multiple quotes on the same house, expect the tonnage to agree closely; if one is a full size larger or smaller than the others, ask why.

If your system does need replacing this season, our AC replacement and installation page covers what a properly scoped job looks like from quote to startup, and it connects you with local pros who work from an actual load calculation rather than a rule of thumb.

The bottom line: a huge share of Fort Bend's houses were built close together in time, so their first AC replacement is arriving close together too, and the way to control cost isn't guessing at a number — it's insisting on a load calculation and a scope that matches your specific house.