Skansen, a private firm in London, said that the appointment was an important step in changing the gender balance at the company where women make up only 2% of the construction workforce.
In a statement the firm said: "Seeley's understanding of property service requirements will build and foster the long-term client relationships that Skansen enjoys as a boutique business."
Seeley was previously group property director at developer CLS Holdings, in charge of a £850m portfolio. She started her career at property agent Chesterton, moving to General Electric as a project manager co-ordinating relocations, lease negotiations and rent reviews.
CLS took a 25% stake in Skansen in 2002, shortly after it was founded. The developer waived the rent on a building occupied by Skansen for two years as part of the deal.