Redmond's Accessory Structures: The Rules That Matter
Every city handles accessory structures a little differently. In Redmond, Washington, there are 5 distinct rules that residents and property owners should be aware of. Some are stricter than what neighboring cities enforce, and others are more relaxed. Here is what you need to know.
Carport Rules
Carports in Redmond must meet setback and lot coverage rules under RMC 21.08, typically require a building permit for permanent roofed structures, and generally cannot encroach into required front yard setbacks.
Key details: Permit Required: Permanent structures. Code: RMC 21.08. Height Limit: Typically 15 ft. Front Setback: Observe per zone. Lot Coverage: Counts toward maximum.
Contact your local code enforcement office for specific penalty information.
The rules around carport rules in Redmond lean permissive, but that does not mean anything goes.
Garage Conversions
Converting a garage to living space in Redmond requires a building permit and often qualifies as an attached ADU under RMC 21.08; parking replacement, egress, and energy code compliance are required.
Key details: Permit Required: Yes. ADU Option: Up to 1,000 sq ft per RMC 21.08. Egress: Bedroom egress window needed. Energy Code: WA State Energy Code. Parking Rule: Reduced by HB 1337.
Contact your local code enforcement office for specific penalty information.
Tiny Homes
Tiny homes on permanent foundations may be allowed as ADUs under RMC 21.08 if they meet IRC Appendix Q standards; tiny homes on wheels (RVs) are limited to temporary use under RMC parking rules.
Key details: Permanent Tiny Home: Allowed as ADU. IRC Standard: Appendix Q. Tiny Home on Wheels: Not permanent dwelling. Manufactured Homes: Allowed in residential zones. State Law: HB 1337 supports ADUs.
Contact your local code enforcement office for specific penalty information.
ADU Rules
Redmond allows one attached and one detached ADU per single-family lot under RMC 21.08 and WA HB 1337, with no owner-occupancy requirement and streamlined permitting for units up to 1,000 sq ft.
Key details: ADUs Per Lot: Up to 2 (1 attached + 1 detached). Max Size: 1,000 sq ft GFA. Owner Occupancy: Not required. Parking: 1 space per ADU max. State Law: HB 1337.
Contact your local code enforcement office for specific penalty information.
The rules around adu rules in Redmond lean permissive, but that does not mean anything goes.
Shed Rules
Sheds 200 sq ft or smaller are exempt from building permits in Redmond per IRC R105.2 and must meet RMC 21.08 setback and lot coverage rules; larger sheds require building permits.
Key details: Permit-Exempt Size: 200 sq ft or less. Typical Setback: 5 ft rear/side. Zoning Code: RMC 21.08. Electrical Permit: Required separately. Height Limit: Typically 15 ft.
Contact your local code enforcement office for specific penalty information.
The rules around shed rules in Redmond lean permissive, but that does not mean anything goes.
The Bottom Line
Compared to many U.S. cities, Redmond gives residents more room on accessory structures. 3 of the 5 rules here are rated permissive. But permissive does not mean unregulated. There are still requirements, and the city does enforce them when violations are reported.
These rules come from Redmond's publicly available municipal code. For complete penalty schedules, exemption details, and answers to common questions, see the individual ordinance pages throughout this guide.