Generally $65–$90 per square foot of finished area, before things like a bathroom, egress window, wet bar or moisture work.
So a straightforward 1,000-square-foot basement is realistically a $65,000–$90,000 project before those extras.
Basements are one of the better opportunities to add usable space to a house without actually making the house bigger. But there’s one thing I want to get out of the way before we talk about flooring, bathrooms or anything else.
The basement needs to be dry first.
Every price on this page assumes it is.
If it isn’t, we solve that problem before we cover anything up.
Basements are one of the few projects where square footage gives us a decent starting point. More finished space means more framing, insulation, electrical, drywall, flooring, trim and lighting.
Our starting range is $65–$90 per square foot of finished area. For a standard basement, that means LVP or carpet, drywall, recessed lighting and basic trim. Nothing crazy — just a comfortable finished space that feels like part of the house.
| Finished area | Starting range |
|---|---|
| 600 sq ft | $39,000–$54,000 |
| 800 sq ft | $52,000–$72,000 |
| 1,000 sq ft | $65,000–$90,000 |
| 1,200 sq ft | $78,000–$108,000 |
Those numbers are for the finished living space itself. Bathrooms, egress windows, wet bars and moisture remediation are separate. That distinction matters.
This is one of the easiest places to control the budget. If you have a 1,200-square-foot basement, that doesn’t mean you need 1,200 finished square feet. Maybe 800 square feet gives you the family room, playroom and office you actually want.
Leave the mechanical room alone. Leave yourself some unfinished storage. There’s nothing wrong with that.
In fact, I usually like having some unfinished basement space. You need somewhere for the water heater, electrical panel and other mechanical equipment, and you need access to those things when they eventually need service. And storage is useful.
There’s no prize for finishing every square foot of concrete in the house.
A standard basement is pretty straightforward.
LVP or carpet.
Drywall.
Recessed lighting.
Basic trim.
A clean finished ceiling.
For a family room, playroom, workout area or office, that may be everything you need. You don’t have to turn the basement into a custom bar and movie theater just because you’re finishing it. Spend money where it makes the space more useful.
If you want better flooring, built-ins, a more involved ceiling treatment or a real lighting plan, that moves the project into our upgraded finish level. Upgraded finishes generally add about 22% to the base basement cost. That can absolutely be worth it if the basement is going to function as a major part of the house. It just needs to be part of the budget from the beginning.
This is probably the most common major addition to a basement project.
| Bathroom | Adds |
|---|---|
| Half bath — toilet and sink | $9,000–$15,000 |
| Full bath — toilet, sink and shower | $20,000–$30,000 |
The plumbing underneath the basement is what makes either one simple or complicated. If the drain lines are already under the slab where we need them, great. If they aren’t, we may need to get into the concrete.
And with a full bathroom below grade, gravity may not be able to carry the waste where it needs to go. In that situation the bathroom will usually need a pump to move it up to the house’s drainage system.
That’s why I want to think about the bathroom before the basement floor plan is finalized. Putting it in the right place can make a meaningful difference.
We completed a roughly 950-square-foot finished basement with a half bath for about $80,000. The drain lines were already under the slab on that project.
That mattered. We weren’t starting from scratch trying to figure out how to get bathroom drainage across the basement.
It’s a good example of why I don’t like telling somebody “your neighbor paid this much, so yours should cost the same.” Two basements can be nearly identical in size and still require different amounts of work. What the house gives us to start with matters.
If you want a legal sleeping room in the basement, egress can become part of the project. An egress window is an opening designed to provide emergency escape and rescue from the room. It isn’t just a normal little basement window.
Installing one can involve cutting the foundation wall, installing the window itself, building the exterior window well and making sure water is properly managed around it.
If you’re thinking about putting a bedroom downstairs, bring that up early. We want the floor plan built around those requirements instead of trying to solve them after everything else has already been designed.
A wet bar can be a great addition if you’re actually going to use it. That figure can involve cabinetry, countertops, a sink, plumbing, electrical and potentially appliances.
Again, location matters. Putting the wet bar relatively close to existing plumbing is very different from deciding it belongs on the opposite side of the basement. That doesn’t mean we can’t put it there — it just means the floor plan affects the construction cost.
This is the part I’m least flexible about. If the basement has a moisture problem, we do not finish over it.
Moisture remediation can add roughly $6,000–$18,000, depending on what needs correcting. That cost is separate from the basement finishing price. And it needs to happen first.
A basement can look dry when we walk through it and still have a history of water.
Look for staining.
Ask what happens during a hard rain.
Pay attention to musty smells.
Find out whether the sump pump runs regularly.
Look at where the downspouts discharge outside.
If there’s a moisture problem, figure out where the water is coming from and deal with it.
Drywall doesn’t fix a wet basement. Neither does flooring. Covering the problem just makes it harder and more expensive to fix later.
It’s easy to look at the square-foot number, do some quick maths and assume that’s the whole project. It may not be. The base rate covers the standard finished living space. It does not include:
| Not included | Add |
|---|---|
| Half bathroom | $9,000–$15,000 |
| Full bathroom | $20,000–$30,000 |
| Egress window | $5,000–$9,000 |
| Wet bar | $8,000–$18,000 |
| Moisture remediation | $6,000–$18,000 |
Upgraded finishes also move the base price higher. And these things can stack.
Take a 1,000-square-foot basement. The base finished space starts around $65,000–$90,000. Add a full bathroom, wet bar and egress window and you now have another $33,000–$57,000 worth of features in the project.
That is a very different basement. Make sure the number you’re comparing actually includes the basement you’re picturing.
One contractor says $60,000. Another says $85,000. Another says $110,000. Before deciding somebody is overpriced, look at what each person actually included.
The bottom line doesn’t tell you much if the scopes aren’t the same. This is why I like a detailed scope of work. You should be able to understand what you’re buying without knowing construction jargon.
This is where I’d start, before worrying about finishes. What do you need downstairs?
Somewhere for the kids.
A family room and a bathroom.
An office, if you work from home.
A guest room.
A gym.
Those answers determine the floor plan. And the floor plan determines a lot of the cost. A basement with one big open family room is a different project from a basement divided into a bedroom, office, bathroom, bar and living room.
Same concrete box. Different project.
Around Selinsgrove, Lewisburg, Sunbury, Northumberland, Danville, Shamokin Dam, Milton, Watsontown and the rest of the Susquehanna Valley, plenty of homes already have substantial basement space sitting underneath them.
If the basement is dry and has enough usable height, finishing it can be a practical way to gain living space without building an addition.
The foundation is already there.
The roof is already there.
The space already exists.
That doesn’t make finishing it cheap. But it does mean you may be able to get the family room, office, bathroom or extra usable space you need without making the footprint of the house any bigger.
If you’re six months or a year away, you don’t need three contractors walking through the house yet. Put in the approximate amount of space you want to finish and the features you’re considering, and you’ll get a realistic starting range.
If the number works for your budget, the next step is a fifteen minute phone call. Get the number in the right neighborhood first. Then figure out the details.
Fifteen minutes on the phone. You’ll have a realistic range before we hang up — and if we’re not the right people for it, I’ll tell you.