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  • Average homeowner rating star icon4.4
    Average homeowner rating
  • Verified reviews icon47
    Verified basement waterproofing services reviews

Verified Reviews for Basement Waterproofing pros in West Islip, NY

*The Angi rating for Basement Waterproofing companies in West Islip, NY is a rating based on verified reviews from our community of homeowners who have used these pros to meet their Basement Waterproofing needs.

*The HomeAdvisor rating for Basement Waterproofing companies in West Islip, NY is a rating based on verified reviews from our community of homeowners who have used these pros to meet their Basement Waterproofing needs.

Last update on October 05, 2025

Find Basement waterproofing pros in West Islip

Basement Man

5.00(
16
)
•Approved Pro

Basement Man

5.00(
16
)
•Approved Pro
Customers say: Quick response
Recommended by 93% of Angi customers
Recommended by 93% of HomeAdvisor customers
14 local quotes requested

WHY--THIS IS A JOB FOR BASEMENT MAN!!! Your locally owned and operated Basement Waterproofing Specialist. Why am I YOUR Basement Waterproofing Specialist? Because over a 38 year period, I've built over 110 customer homes all over Long Island and I know Basements! We stand behind and guarantee all of our work, so give us a call anytime for a free estimate.

"Things went great I'd hire him again"

John R on May 2025

WHY--THIS IS A JOB FOR BASEMENT MAN!!! Your locally owned and operated Basement Waterproofing Specialist. Why am I YOUR Basement Waterproofing Specialist? Because over a 38 year period, I've built over 110 customer homes all over Long Island and I know Basements! We stand behind and guarantee all of our work, so give us a call anytime for a free estimate.

"Things went great I'd hire him again"

John R on May 2025

Avatar for Lorenzo Napolitano Construction Inc.

Lorenzo Napolitano Construction Inc.

4 Quogue Plaza Trail
4.94(
16
)
•Approved Pro

Lorenzo Napolitano Construction Inc.

4 Quogue Plaza Trail
4.94(
16
)
•Approved Pro
Customers say: Quick response
Recommended by 93% of Angi customers
Recommended by 93% of HomeAdvisor customers
31 years of experience

We're dedicated to providing our clients with the very best in concrete installation for driveways, sidewalks, patios, steps, and a variety of other projects. We also specialize in all Stone Work including fireplace installations, pavers, & stucco siding. With over 25 years of industry experience, we take and enormous amount of pride in the attention to detail put into each of the projects we're involved with. We're known for our quality work and the integrity of our business. We look forward to building long-term relationships with our clients, and guarantee your satisfaction.

"Great knowledgable guys. Very happy with their work"

Vincent R on September 2025

We're dedicated to providing our clients with the very best in concrete installation for driveways, sidewalks, patios, steps, and a variety of other projects. We also specialize in all Stone Work including fireplace installations, pavers, & stucco siding. With over 25 years of industry experience, we take and enormous amount of pride in the attention to detail put into each of the projects we're involved with. We're known for our quality work and the integrity of our business. We look forward to building long-term relationships with our clients, and guarantee your satisfaction.

"Great knowledgable guys. Very happy with their work"

Vincent R on September 2025

Avatar for Zavza Seal, LLC

Zavza Seal, LLC

377 Main St. Suite 6
4.92(
43
)
•Approved Pro

Zavza Seal, LLC

377 Main St. Suite 6
4.92(
43
)
•Approved Pro
Customers say: Quick response
Recommended by 95% of Angi customers
Recommended by 95% of HomeAdvisor customers
31 local quotes requested

Zavza Seal is an experienced high end general contracting firm with a passion for delivering excellence. Serving Long Island communities including Suffolk, and Nassau counties. We are a one-stop shop construction company that specializes in the following: waterproofing basements, paving and sealing driveways and garages, waterproofing parking structure and concrete commercial roofs. Concrete Swimming pool buildout, Stone paving and tuck-pointing work. If you are considering any type of waterproofing project and concrete work we are here to help and can provide valuable, time-saving advice. We also specialize in waterproof concrete for professional and residential use called Basecrete. Call today for a free estimate!

"I hired Zavza Seal to waterproof my basement and they did an exceptional job! The team was professional, thorough and went the extra mile to ensure everything was done perfectly. I'm happy with their work and highly recommend them to anyone!"

Levan C on September 2024

Zavza Seal is an experienced high end general contracting firm with a passion for delivering excellence. Serving Long Island communities including Suffolk, and Nassau counties. We are a one-stop shop construction company that specializes in the following: waterproofing basements, paving and sealing driveways and garages, waterproofing parking structure and concrete commercial roofs. Concrete Swimming pool buildout, Stone paving and tuck-pointing work. If you are considering any type of waterproofing project and concrete work we are here to help and can provide valuable, time-saving advice. We also specialize in waterproof concrete for professional and residential use called Basecrete. Call today for a free estimate!

"I hired Zavza Seal to waterproof my basement and they did an exceptional job! The team was professional, thorough and went the extra mile to ensure everything was done perfectly. I'm happy with their work and highly recommend them to anyone!"

Levan C on September 2024

Diamond Masonry & Waterproofing

1378 Whittier Avenue
5.00(
5
)

Diamond Masonry & Waterproofing

1378 Whittier Avenue
5.00(
5
)
58 local quotes requested

Diamond Masonry & Waterproofing was founded on a passion for the trade. We have been in the masonry and basement waterproofing trade since 1988 and formed diamond masonry & waterproofing in 2000.our knowledge and expertise of the industry has led us to small jobs and large scale commercial projects. No job is the same so we enjoy the challenges of all projects.

Diamond Masonry & Waterproofing was founded on a passion for the trade. We have been in the masonry and basement waterproofing trade since 1988 and formed diamond masonry & waterproofing in 2000.our knowledge and expertise of the industry has led us to small jobs and large scale commercial projects. No job is the same so we enjoy the challenges of all projects.

E. Bludaj Construction Inc

2047 Holland Avenue
5.00(
3
)

E. Bludaj Construction Inc

2047 Holland Avenue
5.00(
3
)
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers

We pride ourselves on the quality work we provide, while delivering great customer service. Check out our services offered and call or click to schedule an estimate today!

"Eddie and his crew solved my flooding issues with the installation of new pumps and delivered innovation solutions for a complicated problem, in the best efficient ways. His work was clean efficient, immaculate honest and on time. his company was accountable and delivered exactly what I requested and needed. Fortunately for me he will be returning soon to continue to address a few other projects on my list. I'm confident anyone that hires this company will be extremely pleased. A number of my personal friends have hired his team and were pleased with no regrets. Terry"

Theresa L on June 2024

We pride ourselves on the quality work we provide, while delivering great customer service. Check out our services offered and call or click to schedule an estimate today!

"Eddie and his crew solved my flooding issues with the installation of new pumps and delivered innovation solutions for a complicated problem, in the best efficient ways. His work was clean efficient, immaculate honest and on time. his company was accountable and delivered exactly what I requested and needed. Fortunately for me he will be returning soon to continue to address a few other projects on my list. I'm confident anyone that hires this company will be extremely pleased. A number of my personal friends have hired his team and were pleased with no regrets. Terry"

Theresa L on June 2024

Oscar’s complete landscaping

Located In:
5.00(
8
)

Oscar’s complete landscaping

Located In:
5.00(
8
)
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers

We specialize in all phases of landscaping, hardscaping, lawn maintenance, fertilization, masonry, pool services, housecleaning and more. We guarantee your satisfaction, and we won’t leave until the job is done right. We pride ourselves on the quality work we provide, while delivering great customer service. As an added bonus, your first week of lawn maintenance is free! Call -or- click to schedule a free estimate today!

"Eric, Oscar and crew were an absolute pleasure to work with. They are true craftsman and did a fantastic Job on my driveway. They completed the job very quickly, cleaning up at the end of each day. I give Dream Pro Care my highest recommendation!"

Ron L on October 2024

We specialize in all phases of landscaping, hardscaping, lawn maintenance, fertilization, masonry, pool services, housecleaning and more. We guarantee your satisfaction, and we won’t leave until the job is done right. We pride ourselves on the quality work we provide, while delivering great customer service. As an added bonus, your first week of lawn maintenance is free! Call -or- click to schedule a free estimate today!

"Eric, Oscar and crew were an absolute pleasure to work with. They are true craftsman and did a fantastic Job on my driveway. They completed the job very quickly, cleaning up at the end of each day. I give Dream Pro Care my highest recommendation!"

Ron L on October 2024

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Showing 1-10 of 202
Basement Waterproofing questions, answered by experts

Finishing an unfinished basement adds the most value, with an average return of 70% or $22,400. A bathroom addition in the basement will provide an ROI of 75%, but the higher cost will leave you with a lower actual return of $9,000, on average. Finishing a basement and adding a kitchen, bathroom, and bedroom to rent the space will leave you with the highest possible ROI, as you could see well over 100% if you rent the space out long-term.

Preventing future basement flooding often involves installing sump pumps, improving drainage, sealing foundation cracks, and maintaining gutters. Costs vary, but preventive measures can range from a few hundred to several thousand dollars, depending on the solutions chosen. Investing in prevention can save you money on future flooded basement cleanup costs and repairs.

Pooling or standing water in your basement should be cause for alarm and action. This indicates that there is a leak or a drainage issue, and until you repair the root of the problem, the situation will only happen again or grow in severity. It’s important to deal with water damage as soon as it occurs.

Yes, crawl spaces can attract bugs, especially since moisture tends to build up in the space, and moisture attracts pests. A good way to prevent pest infestation in your crawl space is to install a vapor barrier—called crawl space encapsulation—on the interior to seal the space, along with a French drain or some other kind of foundation drainage system outside to keep runoff out of your crawl space. You can also seal foundation cracks and repair damages to cut off access to pests.

Water damage to concrete is often gradual and can take months, if not years, for a concrete structure to be fully destroyed. The process often starts with cracks on the surface, followed by sinking slabs and eventually crumbling cement. Therefore, it is important to repair minor damages early to prevent the situation from worsening.

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The West Islip, NY homeowners’ guide to basement waterproofing services

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