Nearly 50 permits were issued at Sarnia City Hall in May.
The building department said a total of 48 permits were handed out, totaling just over $5.85 million.
The largest permit was for $1.45 million for a building at Suncor on River Road, to house a new air compressor and air dryer.
A $600,000 permit was issued for the conversion of a two-storey office at 500 Exmouth Street into apartments.
The latest monthly statistics bring year-to-date construction value to $26.5 million, down slightly from $29.6 million during the first five months of 2024.
Year-over-year construction activity is also lower, with a total of 150 permits issued so far in 2025, compared to 165 during the same timeframe last year.
To date, the city has issued five permits for single-family dwellings.