Üprus analyzed architecture employing an interdisciplinary method, which looked at both functional use and natural features in regard to construction and cultural significance.

Although under Khrushchev's regime preservation and restoration were not a priority, her comprehensive work to uncover the architectural history of the medieval town center of Tallinn and develop a conservation plan, was eventually adopted in 1966.

[16] One project involved inventorying and photographing historic buildings in Kuressaare on Saaremaa Island,[17] while others examined the work of silversmiths, stone markers, and illustrations of the poem Kalevipoeg.

[20] Her views were at odds with Khrushchev's policies, which eliminated restoration budgets as a waste of state funds and favored low-cost developments based on large-scale prefabricated panel construction.

She presented a paper on the revitalization of the center of Tallinn at a 1971 conference in Lübeck, in West Germany[11][19] and traveled to a symposium of the International Council on Monuments and Sites (ICOMOS) held in Vilnius, Lithuania, in 1972.

This method was completely new to the evaluation of medieval buildings in Estonia and her work revealed that as a result of various factors influencing construction, there was no singular dominant style.

[29][Notes 5] In attempting to reconstruct the area, she developed a comprehensive plan on how to preserve the historical buildings while addressing functional zoning and urban renewal.

[11] Her ideas meant limiting developments liable to promote traffic and attract tourists, instead focusing on small restaurants and cafes, with spaces that served the local population.

[30] Üprus began inventorying Estonia's manor houses at the request of Fredi-Armand Tomps [et], who in the 1970s was leading the restoration of estates in the Lahemaa National Park.

[35] Using pre-World War I-era topographical maps and an address directory, she and her team had to compare German, Estonian, and Russian place names to create the list of 2267 manors.

[36] Although she published reports and articles on the progress of her research, her untimely death left Juhan Maiste in charge of assembling a team to complete the project.

[1] According to historian Anneli Randla [et],[16] Üprus was the "leading specialist" on architecture in Estonia, while Lilian Hansar [et], heritage conservationist for the Estonian Academy of Arts, called her work "outstanding" noting that her study on Tallinn's historical center led to its becoming protected by the state and fostered new research.

[29] Üprus was posthumously honored, along with the other authors of History of Estonian Art, the Nõukogude Eesti preemia (Prize of Soviet Estonia) in 1980,[25] and commemorated on her birthday by newspapers in every decade from 1981 to the twenty-first century.

Directed by Aime Kala and written by Airi Kasera, who also narrated the production, it told the story of Helmi and Hilda Üprus, through interviews with their friends and colleagues.