Rear House Expansion – ACC Design Guidelines

1. ACC Approval Is Required Before Any City Permit Application

All exterior additions, expansions, decks, patios, or structural modifications must receive written ACC approval before construction begins.
City permits do not override HOA requirements.

Parallel Permit Option (At Owner’s Risk)

To reduce long City permitting lead times, a homeowner may choose to submit for City permits in parallel with the ACC review, but only at their own risk.

• ACC approval is not guaranteed, even if the City issues a permit.

• If the ACC requires changes or denies the project, the homeowner is responsible for:

  • Revising City plans

  • Resubmitting to the City

  • Paying any additional City fees

  • Any delays caused by redesign or re‑review

Construction may not begin until both ACC approval and City approval are obtained.

2. What Homeowners Must Submit

A complete ACC submission must be uploaded as a formal ACC request in TownSQ.
The ACC’s 30‑day review period begins only after all required documents are received.

Required Documents

Full Architectural Plan Set

• Floor plans

• Elevations

• Foundation and roof plans

• Structural notes

• Any revisions submitted to the City

• All plans must be scaled and dimensioned

Scaled Site Plan showing:

• Lot boundaries

• All building setback lines

• Distances from the addition to each property line

• All utility and drainage easements

• Existing home and proposed addition footprints

• North arrow and scale bar

Recorded Plat Map

Must show all recorded setbacks and easements.

Boundary Survey

Required if the addition is near any setback or easement.
Must include staked corners and measured distances to structures.

City of Sammamish Permit Documentation

• Approved building permit (if issued)

• Approved site plan

• Inspection card

• Final approval or Certificate of Completion (if applicable)

Photographs of the Addition Area

• All sides of the home

• Distances to fences or property lines

• Any grading or drainage changes

Drainage Information

• Any modifications to drainage

• Any piping installed

• Any grading changes

• Roof runoff redirection

3. Applicable CC&R Requirements (With Updated Rear‑Yard Rules)

Setbacks (CC&R + City Requirements)

No structure may be placed:

• Closer than 20 ft to the front lot line

• Closer than 5 ft to any interior side lot line

• Closer than 10 ft to the exterior street side on corner lots

Rear Setback – CC&R Standard (More Stringent Than City Code)

To preserve privacy and consistent rear‑yard open space:

• No structure of any kind may be located within 20 feet of the rear property line.

• This CC&R standard is more restrictive than the City’s 20‑ft average / 15‑ft minimum rule and therefore takes precedence.

“Structure” includes:

• House additions

• Covered patios

• Raised decks

• Low decks (even under 18")

• Concrete patios / flatwork

• Pergolas, gazebos, or any vertical element

• Any improvement with posts, footings, or hardscape mass

Utility & Drainage Easements

A 5‑ft easement exists along the front, rear, and both interior side lot lines.

Within this easement:

• No structures

• No patios or decks

• No grading or soil modification

• No trees or large shrubs

• No fencing or hardscape

Single‑Family Dwelling Standard

Each lot is limited to one single‑family dwelling, defined as:

• One dwelling unit

• One household

• One kitchen

• No secondary units, rentable suites, or independent living spaces

Additions must not create a second dwelling unit or separate occupancy.

Fence Placement

• Fences may not extend past the front plane of the house.

• The garage is not considered the front of the house for this rule.

4. ACC Review Process

Once the complete packet is submitted:

• ACC verifies compliance with setbacks, easements, and CC&Rs

• ACC confirms the addition does not create a second dwelling unit

• ACC reviews architectural compatibility

• ACC determines whether modifications are required

Homeowners will receive written approval, conditional approval, or denial.

5. Construction Requirements

• Construction must match the ACC‑approved plans exactly

• Any change requires a new ACC review

• Work started without ACC approval may result in enforcement action

6. Summary of Required Steps

1. Prepare full architectural plans

2. Upload complete submission to TownSQ

3. ACC reviews and issues approval

4. Apply for City of Sammamish permits (parallel submission allowed at owner’s risk)

5. Begin construction only after both approvals are in place