House at 121 South Ridge
Also known as: Hobart Welded Steel House
Why it's listed
Built in 1940 in Troy's Edgehill subdivision, this two-story house was made almost entirely of lightweight welded steel, including the roof, interior and exterior walls, staircase and even the kitchen cabinets. The Hobart brothers designed and built it, and the sections were prefabricated at the company's factory on West Main Street and trucked to the site. It was constructed as a rental and first leased to a man affiliated with the Steel House Company. The Georgian Revival design, a variation of Colonial Revival, features a central entrance with a small hood on four Doric columns, a circular window above the door, a central chimney and original sixteen-light casement windows. Later changes include asphalt shingles over the steel roof, a rear enclosed porch and a side carport. It is one of 21 surviving Hobart steel houses and one of ten in Edgehill, and it was listed for its unusual construction, material and style, and as a continuation of the Hobarts' steel housing work begun in the early 1930s.
Significance in brief: It is one of 21 remaining Hobart welded steel houses and one of 10 steel houses in the Edgehill plat. It is significant for its unique construction, material and Georgian Revival style. Because it is less than 50 years old, it was justified as a continuation of the Hobarts' early 1930s venture into steel housing.
Machine-generated summary. This summary was generated by a language model from the official nomination document and has not been reviewed line by line by an editor. It may contain errors. Check the source document before relying on any detail. Source: nomination document (PDF) · National Archives catalog entry. NRHP reference 89000425, listed May 25, 1989. Summary generated October 2026 (model claude-sonnet-5-5, prompt v1.0-2026-10-29, confidence high).
Key facts
| Address | 121 S. Ridge, Troy |
|---|---|
| County | Miami County |
| Listed | May 25, 1989 |
| Reference number | 89000425 |
| Resource type | Building |
| Period of significance | 1940 |
| Architect / builder | Hobart Welded Steel House Co (designed and built by the Hobart brothers) |
| Architectural style | Georgian Revival |
| Criteria |
|
| Areas of significance | Industry, Engineering, Architecture |
| Level of significance | State |
| Status (as stated in the nomination) | Interior in good condition and exterior in very good condition; original steel roof replaced with asphalt shingles, with a rear enclosed porch and side carport added. |
| Acreage | 0.3 |
| Coordinates | 40.04472, -84.21746 (NPS GIS) |
What listing means for this property
National Register listing is honorary for a privately owned home: it does not by itself restrict what an owner may do with their own money, and it does not require public access. Restrictions come from local landmark or historic-district ordinances, which are separate (how they differ).
Owner-occupied houses are not eligible for the 20% federal rehabilitation tax credit, which applies to income-producing buildings, but many states offer credits for homeowners. Listing also opens the door to preservation easements and to buying a plaque. Start with what listing means for homeowners, renovating a listed house and selling one.
General information, not legal or tax advice. Rules change; confirm with your State Historic Preservation Office or a qualified adviser.
Sources and further reading
- National Park Service, National Register of Historic Places database (snapshot May 2026), reference 89000425.
- Nomination form (PDF, National Archives) — catalog entry
- Wikidata Q138589768
- This listing as JSON
Last updated October 2026. Found an error? See the editorial policy for how to report it.