When Does a Mid-Century House Become Historic?

Every generation is convinced that historic means the houses their grandparents grew up in, and every generation is wrong about it in the same way.

Historic is not a fixed date. It is a rolling threshold. The postwar houses that people casually dismissed as too new to matter have been quietly entering the preservation conversation for years, and the ones built after them are next.

That has practical consequences for anybody who owns a mid-century house and is planning to change it.

Why age thresholds move

Preservation programs almost always include some idea of a minimum age, because you need distance to judge significance. Something built last decade cannot yet be evaluated for how it fits into a pattern of development, because the pattern is not finished.

The threshold is a rolling window, not a fixed year. Which means buildings cross into eligibility on a schedule, continuously, forever. The mid-century stock is not becoming historic because tastes changed. It is becoming historic because the calendar moved.

What the specific thresholds and criteria are in any given program, and which of them touch a specific Claremont parcel, is a question for the City of Claremont. Do not assume from the general pattern.

Why postwar houses get treated badly

Three reasons, and they compound.

Familiarity. There are a lot of them, they are still in ordinary use, and abundance reads as ordinariness. The same was true of bungalows once.

Modesty of means. Much of the postwar stock was efficiently built for a mass market. People confuse economy of construction with lack of design intent, which misreads the entire era.

They are easy to erase. Simple volumes, open plans, and inexpensive finishes make them cheap to remodel, so they get remodeled more casually than a house with elaborate original woodwork.

The result is that the most distinctive features of a mid-century house are exactly the ones people remove first: original windows and their thin frames, the flat or low-slope roof profile, the material palette, the connection between inside and outside, the built-in cabinetry, and the original kitchen and bath fixtures.

What actually makes one of these houses significant

The same families of criteria that apply to anything else. Association with a pattern of development, connection with a designer or builder whose work is regarded as significant, embodiment of a style or construction method, and integrity.

Integrity is again the gatekeeper. A postwar house that still reads as what it was, with its window pattern intact and its original massing legible, is a candidate. The same house with vinyl windows in resized openings, a pitched roof added over the original flat one, and the interior opened up is not, however tidy it looks.

The full framework is set out in what makes a home historic, officially, and the integrity argument matters just as much here as it does on a 1912 bungalow.

The practical advice for an owner right now

You do not need to seek designation, and this is not an argument that you should. It is an argument about what to stop throwing away.

Stop removing original windows. The window pattern and the frame profiles are the single most character-defining element of most postwar houses, and stock replacements almost never match the proportions.

Keep the roof profile. Adding a pitched roof over a low-slope original is the most common irreversible change made to these houses.

Keep original built-ins and cabinetry where you can. They were often designed for the specific house and they cannot be bought.

Keep the material palette legible. Original masonry, wood, and panel materials, and the way they meet, are the design.

Do not stucco over things. A universal rule for every era of house, and a particular temptation on this one.

And apply the same test that governs every old-house decision: can the next owner undo this? The argument is developed in reversible change.

What this means at a sale

Buyers who specifically want mid-century houses are looking for original material, and they are increasingly able to tell the difference between an intact house and a flipped one. Original condition, even tired original condition, is often more marketable to that buyer than a generic renovation.

Which is why the documentation habit matters here too. If original elements were kept, restored, or carefully stored, say so with evidence. That is the same provenance argument made in telling a home's story.

The mistake people make with recent eras generally

Here is the pattern, and it repeats reliably enough to be worth naming.

A style is built in quantity. A generation later it is unfashionable, and people alter it freely because it is everywhere and nobody is precious about it. A generation after that, the surviving intact examples are scarce, they become desirable, and everyone wonders why so few were left alone.

That cycle has already run once on the bungalows. It ran again on the postwar stock. It is running now on what came after, and the houses currently being remodelled without a second thought are the ones somebody will be hunting for later.

You cannot predict taste. You can predict scarcity, and scarcity is created by exactly the decisions being made this decade.

The honest summary

If you own a postwar house, you are probably its second or third family, and you are making decisions that a future preservation conversation will judge.

You are not obliged to freeze it. You are simply better off knowing that too new to matter is a temporary condition, and that the material you remove this year is the material somebody will wish had survived.

Whether any designation applies to your specific address today is a question for the City of Claremont, and it should be asked before you plan work rather than after.

More across the subject in the historic homes hub. Anthony Grynchal has been licensed in California since November 2009.