By Korey Welch, Owner of Boom Realty 
and Senior Mortgage Broker, Loan Factory 

Here’s a thoughtfully professional yet slightly whimsical guide to planning an accessory dwelling unit:
Accessory dwelling units – affectionately known as ADUs, granny flats, in-law suites, or backyard cottages – are gaining popularity for good reason. Whether you’re dreaming of a cozy retreat for guests, a rental opportunity, or a private office away from the bustle of the main house, planning an ADU requires careful thought and a little creative spark.
Here’s a guide to help you navigate the process with clarity and just a hint of charm:
Understand local regulations
Before you draw up plans or pick out charming window boxes, research your local zoning ordinances and building codes. Every municipality has its own rules about ADU size, placement, occupancy, and utilities.
Key questions to answer:
• Is an ADU allowed on my property?
• What are the size limits and setback requirements?
• Are there parking or height restrictions?
• What permits and inspections are required?
Pro tip: A chat with your local planning department can save you from costly surprises later.
Define the purpose
What is your ADU’s destiny? A long-term rental? A guest cottage? A studio where you’ll finally write your novel? Knowing the intended use will shape the design, layout, and amenities.
Fun suggestion: Give your ADU a nickname during the planning phase – “The Nook,” “Studio 42,” or “The Hedgehog’s Hideaway” – to make the process feel more personal and engaging.
Set a realistic budget (with a cushion for the unexpected)
ADUs can be surprisingly cost-effective or unexpectedly pricey, depending on size, finishes, and site conditions. Build a clear budget that includes:
• Design and architectural fees
• Permits and impact fees
• Construction and materials
• Utility connections (water, sewer, electrical)
• Landscaping and exterior features
Wise words: Always tuck away an extra 10-20% for the delightful unpredictability of construction projects.
Design for efficiency and delight
Small spaces demand clever design. Maximize every inch by incorporating:
• Multi-purpose furniture
• Built-in storage
• Lots of natural light
• A connection to outdoor space (a petite patio, anyone?)
Whimsical touch: Don’t be afraid to add a unique design element – a round window, a tiny reading nook, or a bold front door color can give your ADU character without breaking the budget.
Plan for utilities and access (A not-so-glamorous but crucial step)
Consider how your ADU will connect to water, sewer, electrical, and gas lines. Will it share systems with the main house or be entirely separate? Ensure safe, convenient access for future occupants – pathways, lighting, and privacy screening are all part of a thoughtful plan.
Think long-term value
Even if you’re building it for one purpose now, consider how an ADU might evolve over time. Flexible layouts and durable materials can ensure your cozy cottage remains an asset for years to come.

Planning an ADU is equal parts practical strategy and creative adventure. Embrace both. Keep a notebook of ideas, visit inspiring tiny homes, and savor the process. After all, you’re creating not just a building – but a story.

Korey Welch, owner of Boom Realty and Senior Mortgage Broker (NMLS: 14991) with Loan Factory (NMLS: 320841), is a licensed mortgage broker/real estate broker based in Rockland. For more than two decades, Korey has been helping seniors determine the best fit. For a complimentary consultation, contact him at korey@koreywelch.com, 781-367-3351.