Montgomery County Residential Permit Insights

Over 65,268 renovation permits have been completed since 2000. Volume peaked at 4,886 in 2016. The lowest year was 2001 with 1,540 completions. Unlike new construction, renovation activity has shown steady long-term growth, reflecting a sustained preference for improving existing properties.

Single-family dwelling alterations and additions make up the vast majority of completed renovation projects. Accessory structure additions have seen steady growth in recent years, reflecting the trend toward ADUs, detached home offices, and other secondary structures on existing lots.

Renovation permits were historically fast to process — averaging just 11.5 days in 2013. That efficiency has eroded. The longest average wait was 44.4 days in 2021. The most recent full year (2025) averaged 28.8 days. Behind the averages, half of renovation permits are approved within 8 days, but 1 in 10 waits over 54 days. Applications peak in Oct and slow to their lowest point in Feb.

Renovation project timelines have varied widely. The fastest year was 2016 at 141 days on average, while 2001 saw an average of 345 days — nearly 12 months from permit issuance to final inspection. Once construction begins, 25.7% of inspections result in a failure, adding rework and delays to the timeline.