Do Window Replacements Need a Permit in Montgomery County, MD?
When A Window Swap Usually Stays Permit-Free A straightforward window swap in Montgomery County, MD is often permit exempt if the new unit matches the old opening and does not alter the structure. What matters most is not the label on the window, but whether the installation changes the building opening in a way that triggers review. If the replacement unit fits the existing opening and does not require structural alteration, it is often handled as exempt work.