308 foundation repair companies ranked by CR ScoreUpdated 0 paid placements in this rankingHow we rank →
Best overall in Islip: Chris Landscaping & Basement Waterproofing corp, CR Score 62/100; 5.0★ from 74 Google reviews; open 7 days a week.
Best for emergencies (open 24/7): Pappy's Ultimate Construction, Drainage & Waterproofing, posts 24/7 hours; ranked #2 of 308.
Most-reviewed: Genstar Masonry and Landscaping, 479 Google reviews at 5.0★, the most of 308 ranked; ranked #7.
Rankings can't be bought. Contractors can't pay to change their rank or score. How we rank
308 Islip foundation repair companies are ranked here by CR Score, from ten published factors. 76 are open 24/7, 259 open Saturdays and 202 open Sundays, based on posted hours. The median Google rating is 5.0★ across 308 rated businesses.
| Rank | Business | CR Score | Google rating | Based in | Hours | Best for |
|---|---|---|---|---|---|---|
| 1 | Chris Landscaping & Basement Waterproofing corp | 62 | 5.0★ (74) | West Hills, 6 mi away | Sat · Sun | Overall |
| 2 | Pappy's Ultimate Construction, Drainage & Waterproofing | 60 | 5.0★ (102) | Centereach, 11 mi away | 24/7 | Emergencies |
| 3 | HRC Waterproofing | 60 | 4.9★ (77) | Jamaica, 31 mi away | 24/7 | — |
| 4 | Building Structures Unlimited Inc. | 59 | 5.0★ (69) | Melville, 12 mi away | Sat | — |
| 5 | BOCCIA - Waterproofing & Masonry Specialists | 59 | 4.7★ (115) | Garden City Park, 23 mi away | Sat · Sun · Evenings | — |
| 6 | Vulcan Basement Waterproofing | 59 | 4.5★ (23) | Hicksville, 15 mi away | 24/7 | — |
| 7 | Genstar Masonry and Landscaping | 59 | 5.0★ (479) | Massapequa, 13 mi away | Sat · Sun · Evenings | Most reviews |
| 8 | Foundation Crack Repair LLC | Basement Crack Repair | Basement Waterproofing | French Drains | 59 | 5.0★ (15) | Sayville, 7 mi away | Sat · Sun | — |
| 9 | JJM Roofing & Waterproofing | 58 | 4.9★ (93) | Westbury, 18 mi away | 24/7 | — |
| 10 | A.M. Shield Waterproofing Corp. | 58 | 5.0★ (215) | Albertson, 23 mi away | — | — |
Ordered by CR Score, a 0–100 score from ten published factors. Paid placement never changes the order.
Ranked #1 because of its Google rating and trade focus: 5.0★ from 74 Google reviews, listed on Google as “Waterproofing service”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Centereach, 11 mi away
Ranked #2 because of its Google rating and review volume: 5.0★ from 102 Google reviews.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Jamaica, 31 mi away
Ranked #3 because of its Google rating and trade focus: 4.9★ from 77 Google reviews, listed on Google as “Waterproofing service”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Melville, 12 mi away
Ranked #4 because of its Google rating and trade focus: 5.0★ from 69 Google reviews, listed on Google as “Waterproofing service”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Garden City Park, 23 mi away
Ranked #5 because of its Google rating and trade focus: 4.7★ from 115 Google reviews, listed on Google as “Waterproofing service”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Hicksville, 15 mi away
Ranked #6 because of its Google rating and trade focus: 4.5★ from 23 Google reviews, listed on Google as “Waterproofing service”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Massapequa, 13 mi away
Ranked #7 because of its Google rating and review volume: 5.0★ from 479 Google reviews, the most in Islip.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Sayville, 7 mi away
Ranked #8 because of its Google rating and trade focus: 5.0★ from 15 Google reviews, listed on Google as “Waterproofing service”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Westbury, 18 mi away
Ranked #9 because of its Google rating and review volume: 4.9★ from 93 Google reviews.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Albertson, 23 mi away
Ranked #10 because of its Google rating and trade focus: 5.0★ from 215 Google reviews, listed on Google as “Waterproofing service”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Nesconset, 9 mi away
Ranked #11 because of its Google rating and trade focus: 5.0★ from 17 Google reviews, listed on Google as “Waterproofing service”.
Based on 7 of 10 factors; credentials, recency and availability not yet collected.
Based in Bay Shore, 1 mi away
Ranked #12 because of its Google rating and trade focus: 4.7★ from 15 Google reviews, listed on Google as “Waterproofing service”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Medford, 12 mi away
Ranked #13 because of its Google rating and review volume: 4.9★ from 126 Google reviews.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Amityville, 16 mi away
Ranked #14 because of its Google rating and trade focus: 5.0★ from 15 Google reviews, listed on Google as “Waterproofing service”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in West Babylon, 8 mi away
Ranked #15 because of its Google rating and review volume: 5.0★ from 68 Google reviews.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Rye, 31 mi away
Ranked #16 because of its Google rating and trade focus: 4.6★ from 29 Google reviews, listed on Google as “Waterproofing service”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Melville, 13 mi away
Ranked #17 because of its Google rating and review volume: 4.9★ from 95 Google reviews.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Ronkonkoma, 7 mi away
Ranked #18 because of its Google rating and review volume: 5.0★ from 53 Google reviews.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Forest Hills, 19 mi away
Ranked #19 because of its Google rating and trade focus: 5.0★ from 13 Google reviews, listed on Google as “Waterproofing service”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Hell's Kitchen, 16 mi away
Ranked #20 because of its Google rating and trade focus: 5.0★ from 10 Google reviews, listed on Google as “Foundation”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Briarcliff Manor, 39 mi away
Ranked #21 because of its Google rating and trade focus: 5.0★ from 26 Google reviews, listed on Google as “Waterproofing service”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Coram, 17 mi away
Ranked #22 because of its Google rating and review volume: 5.0★ from 408 Google reviews.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Jamaica, 29 mi away
Ranked #23 because of its Google rating and trade focus: 4.7★ from 30 Google reviews, listed on Google as “Waterproofing service”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Huntington, 16 mi away
Ranked #24 because of its Google rating and trade focus: 5.0★ from 3 Google reviews, listed on Google as “Waterproofing service”.
Based on 8 of 10 factors; credentials and recency not yet collected.
Based in Maspeth, 10 mi away
Ranked #25 because of its Google rating and trade focus: 5.0★ from 4 Google reviews, listed on Google as “Waterproofing service”.
Based on 8 of 10 factors; credentials and recency not yet collected.
#1 to #25 are shown in full above. Here are #26 to #50, in CR Score order; each links to its profile. We publish the top 50 of 308 ranked foundation repair companies here; the rest are on their profiles.
20 more foundation repair companies within 40 mi that we can't rank yet: too few reviews, or a trade we couldn't confirm. Listed A to Z.
| Business | Google rating | Distance |
|---|---|---|
| Ajrin Construction Inc. | 5.0★ (2) | 35 mi |
| American Dry Basement Systems | 5.0★ (2) | 29 mi |
| Aslam Roofing and Waterproofing. | 5.0★ (2) | 28 mi |
| Bancker Construction | 3.6★ (28) | In Islip |
| Chimney Genie Liners & Chimney Repair | 4.8★ (47) | In Islip |
| Crown Waterproofing | 4.5★ (2) | 35 mi |
| Diamond NY Construction | 3.0★ (2) | 33 mi |
| Grant’s Customs Carpentry LLC | 5.0★ (2) | 32 mi |
| I.K Construction | 5.0★ (2) | 35 mi |
| Innovate Builders Inc | 3.0★ (2) | 26 mi |
| Liberty Masonry & Waterproofing | 1.0★ (2) | 37 mi |
| Maestro Builders Corporation | 5.0★ (2) | 37 mi |
| Maintenance Experts of Long Island | 3.0★ (2) | 8 mi |
| NYC DOB Local Law 11 Facade Repairs Contractors | 5.0★ (2) | 37 mi |
| Quality Masonry And Foundation Repair | 5.0★ (2) | 31 mi |
| Shoot Installers INC. | 5.0★ (2) | 35 mi |
| Torres Line Construction | 5.0★ (2) | 19 mi |
| Tur Contracting Inc. | 3.0★ (2) | 35 mi |
| ValueDry Basement Waterproofing & Remodeling | 4.0★ (2) | 31 mi |
| Waterproofing Restoration of Baldwin | 5.0★ (2) | 22 mi |
National price ranges in USD, not adjusted for Islip. Each row names its basis and the month we checked it.
| Job | Low | Typical | High | Basis | Checked |
|---|---|---|---|---|---|
| Foundation repair | $2,225 | $5,174 | $8,133 | Per project: typical range of customer-reported repairs. US national range | October 2026 |
We scored 308 Islip foundation repair companies on ten factors, weighted as shown. A business is ranked when its trade is confirmed and it has 3 or more Google reviews or a claimed profile. A business with no Google reviews scores zero on rating, review volume and recency. Other unknown factors are left out, not counted as zero. Scores last refreshed October 22, 2026.
Paid placement never changes a rank or score. Featured businesses are paid, labelled, limited to 3 and shown above the ranking, outside it.
| Factor | Weight | Computed from | In Islip data |
|---|---|---|---|
| Reputation | 25% | Google star rating, adjusted for how many reviews back it | Measured |
| Credentials | 15% | Active state license, bond and workers’ comp on file | Not yet collected |
| Review volume | 10% | Number of Google reviews, compared with the most-reviewed business on the list | Measured |
| Recency | 5% | Share of reviews from the last 12 months | Not yet collected |
| Availability | 5% | Weekly open hours, Saturday, Sunday, 24/7 or same-day | Measured |
| Trade focus | 10% | How clearly the business does this trade (its Google category and name) | Measured |
| Proximity | 5% | Based in the city scores highest, less the farther away it is | Measured |
| Claimed profile | 10% | The business has claimed its ContractorsRanked profile (free or paid earn the same) | Measured |
| Partnered | 5% | The business links to ContractorsRanked from its own website with our badge, checked periodically | Measured |
| ContractorsRanked reviews | 10% | Verified customer reviews collected by ContractorsRanked: their rating and how many there are | Measured |