Finishing a basement is one of the most effective ways to expand your living space and increase your home's value. Whether you're planning to turn it into a home office, guest suite, entertainment hub, or family room, getting started the right way ensures a smoother and safer renovation. In this guide, we walk you through the key first steps in finishing a basement—prioritizing structure, safety, and long-term success.
Before any design decisions are made, assess whether your basement is a candidate for finishing.
Basements are prone to water infiltration. Inspect for:
Damp walls or flooring
Musty odors
Visible mold
If moisture is present, resolving it is non-negotiable. Learn how in our dedicated guide on how to waterproof your basement.
Most local building codes require at least 7 feet of ceiling height for finished spaces. If your basement falls short:
Consider underpinning to lower the floor
Explore benching or house lifting options
These structural modifications can be complex and costly but are often necessary to meet code and comfort standards. You may be able to raise the ceiling height in your basement.
Learn how we transformed a crawlspace into the beautiful, well-lit play area you see above:
Your foundation and support structures must be sound before adding drywall or flooring.
Cracks in concrete walls
Bowed or leaning walls
Water pooling near the foundation
If your home is older—especially a historic Portland property—you may need to repair or reinforce the foundation. Learn more in our article: When to repair the foundation of a historic Portland home.
Basements used as bedrooms or living spaces require a legal egress window for emergency exit.
Must open to the outside
Should be large enough for a person to exit
Often require digging and cutting into the foundation
See our full breakdown on how and why to add an egress window.
Finished basements can include a bathroom, laundry room, or wet bar—each requiring thoughtful plumbing planning.
Drainage: May need an ejector pump if gravity flow isn’t sufficient
Ventilation: Essential for moisture control and air quality
HVAC extension: Ensure proper heating and cooling reach the space
If installing a basement bathroom, review your plumbing infrastructure before walls go up.
Explore the laundry room and bathroom in this Portland basement remodel
Before finishing surfaces, define your space with a clear layout and essential systems.
Walls: Use moisture-resistant drywall or paneling
Ceilings: Options include drop ceilings, exposed joists (painted for aesthetics), or drywall
Floors: Choose durable, water-resistant materials like LVP or tile
Not sure what layout works best? Explore recent trends in our Portland basement remodel design ideas case study.
With permits secured and design finalized:
Frame walls with pressure-treated lumber against concrete
Install rough electrical, plumbing, and HVAC
Schedule inspections before closing walls
This is also the ideal time to run ethernet, speaker wires, or home theater cables.
Basements can feel cold and echoey without proper insulation.
Rigid foam board or spray foam for exterior walls
Rock wool for sound dampening interior walls and ceilings
This step also improves energy efficiency.
Once insulation and inspections are complete:
Hang drywall
Paint with mold-resistant primer
Install flooring, trim, doors, and fixtures
Now your basement truly begins to feel like a natural extension of your home.
While this guide helps you understand where to start when finishing a basement, you may be wondering about cost. We created an article answering this question: How much does a basement remodel cost in Portland? and also have a basement remodel cost calculator to help you better understand your basement remodeling costs.
For personalized guidance, our team at Lamont Bros. is here to help you evaluate, plan, and build a finished basement you’ll love.