John Yeon Speculative House
U.S. National Register of Historic Places
Location	3922 N. Lombard Street Portland, Oregon[1]
Coordinates	45°34′37″N 122°42′27″W / 45.576939°N 122.707569°W / 45.576939; -122.707569
Built	1939[1]
Architect	John Yeon[citation needed]
Architectural style	Modern[citation needed]
NRHP reference No.	07000771[1]
Added to NRHP	October 1, 2007[1]

The John Yeon Speculative House is a historic house located in Portland, Oregon, United States, built in 1939. It was added onto the National Register of Historic Places^[1] on August 1, 2007.^[2] It is one of a series of speculative houses by native Oregon architect and conservationist John Yeon following the critically acclaimed Watzek House (1936). The series included nine houses built between 1938 and 1940 in Lake Oswego and Portland. The houses used a modular design concept that pioneered the use of external plywood as a building material and separate ventilation louvers, which allowed for series of fixed pane glass to be inset between vertical mullions. Yeon is frequently cited as one of the originators of what became known as the Northwest Regional style of architecture.^{[citation needed]}