Basement Resources

Basement Guides for Long Island Homeowners

Costs, permits, ideas, and advice from 580+ basements completed across Nassau and Suffolk Counties.

Exterior Foundation Waterproofing Long Island — Complete Guide (2026)

Exterior foundation waterproofing on Long Island: membrane types, costs ($8,000–$45,000), process steps, and when you need it vs interior drainage.

Basement finishing on Long Island costs $50–$85 per sq ft installed. Here's what affects the price and how to get an accurate estimate.

Interior drainage, sump pumps, and exterior membranes — here's what each costs on Long Island.

Practical basement conversion ideas from 580+ projects — family rooms, home offices, guest rooms, and more.

Sump pump installation costs $800–$3,500 on Long Island. Battery backup systems — yes, you need one.

Everything you need to know about basement permits in Nassau and Suffolk Counties — requirements, costs, and timelines.

Honest review of every wet basement solution — from Band-Aid fixes to permanent drainage systems.

Basement flooding emergency? Here's exactly what to do in the first 24 hours to minimize damage.

Egress windows cost $3,500–$8,000 installed on Long Island. Required for legal basement bedrooms.

The right insulation makes your Long Island basement comfortable year-round. Here's what we spec and why.

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