The physics, craftsmanship, and design freedom of the custom dry-mix gunite shell - built for New England, built for generations
True Luxury Is Structural
In luxury estate construction, the enduring value of a waterscape lives beneath its surface finish - in its structural core.
A true generational pool is an engineered monolith: a shell that holds its geometry against hydrostatic pressure, saturated soil, and decades of New England winters - so the beauty above the waterline never has to compromise.
Liberated from the Mold
The Factory Constraint
Pre-formed shells are shaped by molds and limited by what a highway trailer can carry.
Pneumatic Freedom
Curvilinear forms, monolithic spas, vanishing edges - shaped in place, exactly as drawn.
Because dry-mix gunite is pneumatically projected at high velocity, it compacts instantly upon impact - holding its shape on fully vertical slopes without double-sided formwork. We are not constrained by highway transport dimensions or factory molds. If an architect can draw it, our nozzlemen can shoot it: infinite geometric freedom, seamless monolithic spas, and complex curvilinear forms.
The Case for Custom Gunite
What Gunite Makes Possible
Infinite Geometry
Any shape, any depth profile, any water feature - designed to the site, not to a mold.
Monolithic Strength
A single 5,000 psi concrete shell with no seams, panels, or liner joints.
Engineered for Winter
Designed for ACI Class F3 freeze-thaw exposure - the most demanding classification.
A Generational Asset
Permanent construction that appreciates with the estate and serves the next generation.
Fiberglass
A factory-molded shell delivered by highway and set into the excavation. Shapes and dimensions follow the manufacturer's catalog, and size is limited by road transport.
Vinyl
A flexible liner fitted over engineered panel walls and a prepared floor. Geometry follows the panel system, and the liner is refreshed on a periodic replacement cycle.
The Kinetic Compaction Engine
A Gedney pool is not poured - it is pneumatically driven.
Material meets the receiving substrate at up to 80 mph. That transfer of kinetic energy compacts the matrix in the instant of placement, expelling entrapped air and achieving an ultra-dense state of 135 to 145 lbs per cubic foot.
A compressive strength conventional poured concrete cannot match.
The Geometry of Permanence
The curved radius where the pool floor meets the vertical wall is not an aesthetic tradition - it is advanced structural physics.
The Concave Arch
By engineering a structural curve at the transition point, we put the immense weight of the concrete shell itself to work - actively pushing back against external soil pressures.
Stress Distribution
The geometric arch carries subterranean loads smoothly across a monolithic concrete matrix - no 90-degree corners, no concentrated stress points, only continuous strength.
Mastering the New England Winter
Fairfield and Westchester winters ask more of a subterranean structure than almost any climate in the country. We treat that as a design brief, not an obstacle.
ACI Exposure Class F3
Every Gedney shell is designed to the most demanding freeze-thaw exposure classification in the ACI code - concrete in continuous contact with moisture and cyclic freezing.
Saturated Winter Ground
Coastal Connecticut and New York soils hold winter groundwater against the shell for months. The structure is engineered for that saturation as its normal operating state.
The 91.7% Threshold
Water expands 9% when it freezes. If a concrete's capillary pores pass 91.7% saturation, expanding ice pressurizes the matrix from within. Gedney concrete is engineered to stay far below that threshold - which is why it endures.
A pool that masters its climate is a pool that keeps its promises for decades.
A Shell Engineered to Stay Dry
Freeze-thaw mastery begins at the microscopic level: a concrete matrix so dense that winter moisture simply has nowhere to go.
Ultra-fine silica particles pack the voids between cement grains, closing the capillary network.
Water-Cement Ratio
Held strictly low to minimize pore creation from the first moment of hydration.
Sulfate-Resistant Cement
A formulation chosen for coastal and wetland groundwater chemistry, protecting the shell from within.
Silica Fume Densification
Spherical particles one hundred times smaller than cement grains pack the microscopic voids, bringing permeability to near zero and keeping the shell far from the critical saturation threshold.
Unlimited Staging, Uncompromised Quality
Racing the Hydration Clock
Ready-mix concrete begins hydrating the moment it leaves the plant. Under ASTM C94, it must be placed within 90 minutes - a demanding window when winding estate driveways and congested corridors sit between the plant and the site.
Plant - highway - site: the schedule belongs to the truck.
Hydration Begins at the Nozzle
Dry materials are staged on site and conveyed pneumatically through a small footprint. Because water is introduced only at the nozzle, there is no 90-minute clock - the material is always fresh at the moment of placement.
The result is unlimited architectural staging time: complex geometry can be shot with patience and precision, on the craftsman's schedule rather than the truck's.
Gentle on sensitive drives and landscaping - a small-footprint operation.
The Master Nozzleman
Because water is introduced at the nozzle, the ultimate structural integrity of a dry-mix shell rests in the hands of the nozzleman - decades of hand-eye craft, and the single most important quality variable on the project.
Perpendicular impact, held strictly to prevent sand lensing within the shell.
Stand-off distance, tuned continuously to the geometry being shot.
Reading the surface of the concrete in real time to hold a perfect 0.35-0.40 water-cement ratio, while coordinating with the blowpipe operator to encase the steel skeleton without voids.
The Steel Skeleton
A pool is only as strong as its composite action. Every Gedney shell is built to an engineered, stamped reinforcing schedule - every bar sized, spaced, and tied to the structure's real loads.
A Schedule That Deepens with the Pool
Deformed bars on a stamped engineered schedule: #4 bars at 9-inch vertical and 12-inch horizontal spacing to 6 feet of depth, tightening to 6-inch and 8-inch centers where the water pushes hardest, from 6 to 9 feet.
The Bond Beam and Every Bench
#4 beam bars ring the perimeter at the coping, and reinforcement continues through every step, bench, and sun shelf - with each rebar intersection individually tied.
Complete Encasement
The 6-inch floor carries #3 bars at 12-inch centers both ways, and 90-degree high-velocity shooting wraps the concrete perfectly around the steel - one composite structure.
Monolithic by Method
When a project is built in phases, Gedney's prepared interface rule ensures each day's work bonds into a single continuous structure.
The 45-Degree Bevel
Unfinished edges are sloped to a clean 45-degree profile, preventing the entrapment of rebound and dry sand at the joint.
Mechanical Interlock
The interface is chipped to a rough, saturated surface-dry (SSD) state - an open texture ready to receive the next phase.
A 260-300 psi Bond
At 80 mph impact, paste-rich shotcrete drives directly into the open pore structure, achieving tensile bond strengths of 260-300 psi - pure mechanical integrity, with no reliance on chemical bonding agents.
The Cure: Locking In Watertightness
The engineering is not finished when the shooting stops. If concrete dries prematurely, hydration halts - the shell never reaches the density it was designed for.
The Gedney Cure
A continuous wet cure for a minimum of 7 days - and we champion the 28-day extended cure. Keeping the shell saturated lets the cement hydrate fully, permanently shrinking the capillary pores and reducing the concrete's absorptive capacity by over half before a single drop of pool water is introduced.
Patience, engineered - the quiet final step that locks in watertightness for decades.
Anatomy of a Generational Asset
Compacted Crushed-Stone Base
A minimum 6 inches of compacted crushed stone providing uniform vertical support.
Engineered Steel Curtain
Bar spacing that tightens with depth, every intersection tied, reinforcement through every step and bench.
5,000 psi High-Velocity Gunite
80 mph compaction achieving an ultra-dense, void-free shell.
Curved Structural Radius
The geometric arch carrying external soil pressure with ease.
Silica-Fume Densified Matrix
The microscopic density that masters the F3 freeze-thaw climate.
Built for a Century, Not a Season
A Gedney Pools custom gunite shell is a masterwork of structural physics - a $200,000+ architectural asset engineered to add permanent, generational value to your estate, and to hold its beauty for every summer your family gathers around it.