Downspout Tie-Ins

Downspout tie-ins are one of the most impactful and affordable drainage improvements you can make to your Long Island home. By connecting your roof gutter downspouts to underground piping that directs water away from your foundation, a downspout tie-in eliminates the concentrated water discharge that causes foundation damage, basement flooding, soil erosion, and landscape destruction around the perimeter of your home. Brothers Paving & Masonry installs downspout tie-in systems across Nassau and Suffolk County that permanently solve the problems caused by uncontrolled roof runoff.

Every time it rains, your roof collects an enormous volume of water. A typical Long Island home with a two-thousand-square-foot roof generates over twelve hundred gallons of water from just one inch of rainfall. That water funnels through the gutter system and exits through the downspouts, where it is dumped directly against your foundation in a concentrated stream. Over time, this repeated saturation of the soil around your foundation creates serious problems including hydrostatic pressure against basement walls, soil erosion that undermines walkways and patios, standing water in planting beds, and ice buildup in winter that creates slip-and-fall hazards.

A downspout tie-in solves these problems by intercepting the water at the base of each downspout and routing it through a sealed underground pipe to a discharge point well away from your foundation. The water is carried to a dry well for on-site infiltration, connected to the municipal storm system where available, or discharged at a daylight outlet at the low point of your property. The result is that thousands of gallons of water per storm event are redirected from your foundation to a controlled dispersal location, dramatically reducing the water load on your home's structure and surrounding landscape.

Our downspout tie-in installation begins with an assessment of your gutter system, downspout locations, and existing drainage conditions. We map out the optimal pipe routes from each downspout to the discharge point, planning for the most efficient path that minimizes excavation and disruption to your property. We determine the correct pipe size based on the roof area served by each downspout to ensure the system can handle peak rainfall without backing up.

Installation involves excavating a narrow trench from each downspout to the discharge location. We install solid, non-perforated PVC piping at a consistent downward slope, typically a minimum of one-eighth inch per foot, to maintain reliable gravity flow. At the downspout connection, we use a specially designed adapter that transitions from the rectangular or round downspout to the underground pipe. This connection is sealed to prevent leaks and configured with a debris screen or leaf filter to keep the pipe clear of gutter debris that could cause blockages.

For homes with multiple downspouts, we design the pipe layout to consolidate flows where practical. Several downspouts on the same side of the house can often be connected to a single main line that runs to the discharge point, reducing the amount of piping and excavation needed. For downspouts on opposite sides of the house, separate lines running to individual dry wells or a shared discharge point may be more practical. We design each system for your specific property layout and drainage needs.

The discharge end of the system is just as important as the collection end. On Long Island, dry wells are the most common discharge option for downspout tie-in systems. The collected roof water enters the dry well and gradually percolates into the surrounding soil, managing the water on-site without overwhelming neighboring properties or municipal systems. For properties with access to storm drains, we can connect the system to the public infrastructure where local codes allow. Daylight outlets that release water at the property edge into a swale or natural drainage course are another option for properties with adequate slope and space.

Long Island's specific conditions influence every aspect of our downspout tie-in installations. The high water table in many communities means dry wells must be sized and placed carefully to maintain adequate separation from groundwater. Sandy soils on the South Shore provide excellent percolation but can shift around pipes during heavy saturation, so we use compacted bedding material to keep pipes stable and properly sloped. Clay soils on the North Shore require larger dry wells or supplemental dispersal because they absorb water more slowly. Winter freeze-thaw cycles demand that all piping be installed below the frost line to prevent ice blockages.

One of the most common issues we see on Long Island is downspouts that discharge through splash blocks or short extensions that dump water just a few feet from the foundation. While these devices redirect the immediate stream, the water still saturates the soil close to the house and causes the same long-term problems. Underground downspout tie-ins move the water ten, twenty, or even fifty feet away from your foundation, providing genuine separation that protects your home.

Another frequent problem is homes where previous drainage work used corrugated flexible pipe that has collapsed, separated at joints, or become filled with sediment over time. We replace these failed systems with rigid PVC piping and proper fittings that maintain their shape and flow capacity for decades. If your existing downspout tie-ins are no longer functioning, replacement with quality materials is a worthwhile investment.

After installation, we backfill all trenches, compact the soil, and restore lawn areas with topsoil and seed or sod. The system operates entirely underground with no visible components except small cleanout caps at grade level. We test the system by running water through each downspout connection and verifying flow at the discharge point before the project is complete.

Brothers Paving has helped hundreds of Long Island homeowners eliminate foundation water problems with professional downspout tie-in systems. This is one of the most cost-effective drainage improvements available, and the protection it provides to your home's foundation is invaluable. Contact us for a free evaluation and estimate.