Basement Finishing Long Island

Long Island's Basement Experts Since 2011

Basement Finishing Long Island

Transform your raw concrete basement into a finished living space. LI Basement Pro has finished 580+ basements across Nassau and Suffolk Counties since 2011.

4.9 — 187 Reviews
🏠580+ Basements Completed
Licensed & Insured
🏆BSI Certified

Mon–Sat, 7am–5pm · Free Estimate · No Obligation

Free Estimate — No Obligation

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4.9 Stars — 187 Google Reviews·🏠580+ Basements Completed·📅15 Years on Long Island·Licensed & Insured·🏆BSI Certified Dealer·🌿EPA Lead-Safe Certified·🔨NARI Member·👥14-Person Crew·🔒Nassau & Suffolk Licensed·4.9 Stars — 187 Google Reviews·🏠580+ Basements Completed·📅15 Years on Long Island·Licensed & Insured·🏆BSI Certified Dealer·🌿EPA Lead-Safe Certified·🔨NARI Member·👥14-Person Crew·🔒Nassau & Suffolk Licensed·

Long Island Basement Finishing Experts

The Right Way to Finish a Long Island Basement

Finished basement interior with open plan living space Long Island

Basement finishing on Long Island isn't the same as basement finishing anywhere else. Long Island's high water table, clay-heavy glacial soil, and the prevalence of older construction — Levitt-era ranches, 1960s colonials, split-levels — means you need a contractor who knows these specific challenges. That's been our specialty since 2011.

We've finished basements in Hicksville, Commack, Garden City, Hauppauge, and dozens more Long Island communities. We know which neighborhoods have the worst groundwater issues, which building departments are fastest on permit approvals, and where to expect surprises behind the block walls.

Every basement finishing project we do starts with a moisture assessment. We look for active seepage, efflorescence (salt deposits from water migration), and drainage issues before a single stud goes up. If we find something, we'll tell you — and we can fix it before it becomes your problem after the drywall is up.

What's Included in Our Basement Finishing Service

Steel stud or wood framing
Insulation (rigid foam or batt)
Drywall hanging, taping & finishing
Recessed LED lighting
Drop ceiling or drywall ceiling
LVP or carpet flooring
Baseboards & door casings
Electrical outlets & switches
Bathroom rough-in (optional)
Egress window installation
Permit application & filing
Building department inspections

Basement Finishing Costs on Long Island

$50–$65

per sq ft

Basic Finish

$65–$75

per sq ft

Standard Finish

$75–$85+

per sq ft

Premium Finish

Typical Long Island basement (600–800 sq ft): $30,000–$68,000 · Permits included

LI Basement Pro finishing crew working on a Long Island basement

Our Basement Finishing Process

1

Free Estimate & Measurement

Dan or a senior estimator visits your home, measures the space, discusses your goals, and checks for any moisture or structural issues that need addressing before finishing.

2

Permit Application

Karen files all necessary permits with Nassau or Suffolk County building departments. We handle the paperwork — you just need to be available for the final inspection.

3

Framing & Rough Work

We frame partition walls, run rough electrical and plumbing, install insulation, and create any required egress openings. All work is inspected before closing up walls.

4

Drywall & Ceiling

Drywall hanging, taping, and finishing or drop ceiling grid installation. We achieve smooth, paint-ready surfaces throughout.

5

Flooring & Finishes

Tony and his carpentry team install LVP flooring, baseboards, door casings, and any built-in elements like closets or storage walls.

6

Final Inspection & Walkthrough

Building department final inspection, followed by our walkthrough with you to address any punch list items before we consider the job complete.

Quick Estimate

600 sq ft basic$30,000–$39,000
600 sq ft standard$39,000–$45,000
800 sq ft standard$52,000–$60,000
+ Bathroom rough-in+ $6,000–$12,000
+ Egress window+ $3,500–$8,000

Estimates vary. Free on-site quote required for exact pricing.

📞 Get Free Estimate

Verified Local Work

Recent Basement Finishing Jobs

Real jobs completed by our crew across Nassau and Suffolk Counties.

Basement Finishing in Hicksville, NY
🏠 Basement Finishing
Hicksville, NYMar 2026

650 sq ft basement with LVP flooring, recessed lighting, and egress window

Basement Finishing in Commack, NY
🏠 Basement Finishing
Commack, NYFeb 2026

800 sq ft basement with home office, bathroom rough-in, and drop ceiling

Basement Finishing in Mineola, NY
🏠 Basement Finishing
Mineola, NYFeb 2026

550 sq ft playroom/guest suite conversion with full drywall and LVP

Basement Finishing in Manhasset, NY
🏠 Basement Finishing
Manhasset, NYJan 2026

Full luxury basement finish with wet bar, home theater prep, and bathroom

Basement Finishing in Dix Hills, NY
🏠 Basement Finishing
Dix Hills, NYDec 2025

720 sq ft basement with home gym, storage room, and LVP throughout

Basement Finishing in West Hempstead, NY
🏠 Basement Finishing
West Hempstead, NYNov 2025

600 sq ft basement conversion — new partition walls, drop ceiling, carpet

Got Questions?

Basement Finishing FAQs — Long Island

Basement finishing on Long Island costs $50–$85 per square foot installed. A typical 600 sq ft basement runs $30,000–$51,000; a 1,200 sq ft project can reach $45,000–$102,000. Factors include: LVP vs carpet flooring, drop ceiling vs drywall, bathroom rough-ins, egress window requirements, and Nassau/Suffolk County permit fees.

Get Started Today

Ready to Transform Your Long Island Basement?

Join 580+ Long Island homeowners who chose LI Basement Pro. Free estimates, no pressure, no obligation.

Mon–Sat, 7am–5pm · Free Estimates · No Obligation · Licensed & Insured