Over 200 SFA Pumps, One Building: Inside a 59,000 Sq. Ft. Office-to-Residential Plumbing Conversion Project

Over 200 SFA Pumps, One Building: Inside a 59,000 Sq. Ft. Office-to-Residential Plumbing Conversion Project

Converting an office building into apartments and a hotel is complex work — and when the structure was never designed to support over 110 bathrooms, the plumbing challenge can define the entire project's fate.

That was the reality facing the team behind a major mixed-use adaptive reuse development in Clearwater, Florida. Adaptive reuse is the practice of repurposing an existing building for a new use — in this case, transforming a 59,000-square-foot commercial office building into approximately 80 residential apartments and 40 hotel suites. The building's original plumbing infrastructure was simply not built for this level of density. Gravity-fed drainage stacks were spaced too far apart, and several floors remained occupied by active office tenants throughout construction.

Traditional methods would have required cutting into concrete structural slabs — an invasive, disruptive process that would have meant dust, noise, and nighttime-only work schedules on occupied floors. That approach wasn't feasible.

The solution? A fully pumped, above-floor sanitary drainage system using SFA Saniflo macerating pumps and drain pumps — with more than 200 units deployed across the property.

The Challenge: Too Many Bathrooms, Too Little Infrastructure

Adaptive reuse projects routinely uncover infrastructure surprises, but the plumbing demands here were exceptional. In a building designed for commercial office use, gravity drainage stacks were widely spaced and not aligned with the locations of future residential bathrooms. Most units were planned as two-bedroom, two-bathroom apartments, resulting in hundreds of plumbing fixtures — toilets, lavatories, showers, kitchen sinks, and in-unit laundry — distributed across floors with no straightforward path to conventional drainage.

Adding to the complexity: multiple floors remained live with office tenants under active leases. Any plumbing method that required breaking through concrete slabs would have displaced those tenants and forced night-only construction schedules.

"That many bathrooms using a traditional gravity system just wasn't realistic in this building," said the building owner. "Because the floor below us was occupied, we would've had to do all the plumbing at night. Between the dust, the noise, and shutting down occupied space, it just didn't make sense."

The team needed an above-floor pumped drainage system that was code-compliant, scalable, and could proceed alongside occupied tenancies — without any floor penetrations.

The Solution: A Multi-Product SFA Saniflo Above-Floor Pumping System

The project team selected SFA Saniflo's above-floor pump and macerating system lineup — the Sanibest Pro, Sanicom 1, and Saniswift Pro — as the backbone of the building's entirely new plumbing infrastructure.

Rather than tying into widely scattered existing stacks, all pumps discharged into a newly installed gravity drain line run through hallway ceiling space. This centralized above-floor plumbing network then connected back into the building's existing vertical drain, waste, and vent (DWV) stacks — a clean, efficient solution that required zero structural slab penetration.

Sanibest Pro — Macerating Grinder Pump for Full Bathrooms

In each residential apartment and hotel guest room, a Sanibest Pro heavy-duty macerating grinder pump was installed behind the toilet. This 1 HP macerating system manages wastewater from up to three fixtures simultaneously — toilet, shower, and bathroom lavatory — and is capable of pumping waste up to 25 feet vertically or up to 150 feet horizontally to the soil stack. CSA-certified and IAPMO-listed, it gave the installation team full flexibility in locating bathrooms without dependence on existing stack positions.

→ Full Sanibest Pro specifications

Sanicom 1 — Commercial-Grade Drain Pump for In-Unit Laundry

In each apartment, a Sanicom 1 commercial-grade drain pump managed the in-unit laundry application. With 1.3 HP and the ability to handle high-temperature gray water up to 194°F, it is engineered for demanding residential and commercial applications, draining two fixtures simultaneously with discharge up to 25 feet vertically or 250 feet horizontally.

→ Full Sanicom 1 specifications

Saniswift Pro — Compact Drain Pump for Kitchen Sinks

Each apartment's kitchen sink was served by a Saniswift Pro compact graywater drain pump — an efficient, quiet solution for spaces where gravity drainage isn't practical. Ideal for retrofits, renovations, and adaptive reuse projects, it discharges gray water up to 14 feet vertically or 140 feet horizontally with a space-saving design suited for installation within cabinetry.

→ Full Saniswift Pro specifications

How the System Came Together on Site

The installation team ran a rack-mounted gravity line through the hallway ceiling on each floor. Every pump throughout the floor discharged into that central gravity line, which then tied back into the building's existing DWV stacks. Dedicated vent lines were also routed through the hallway ceiling for all pumped systems.

In a typical two-bedroom, two-bathroom apartment unit:

• One Sanibest Pro per bathroom — handles toilet, shower, and lavatory for each room
• One Sanicom 1 — manages the in-unit laundry connection
• One Saniswift Pro — handles kitchen sink drainage

In each hotel guest room:

• One Sanibest Pro — serves toilet, shower, and lavatory (no kitchen or laundry required)

Horizontal discharge runs from each unit ranged from 10 to 30 feet, with approximately 10 feet of vertical lift, feeding into the hallway gravity line.

Installation was phased, beginning with seven units and 14 bathrooms. After the initial learning curve on the first unit, the crew progressed to completing one to two units per day.

"The first week was really just diving in and figuring everything out," said the plumbing subcontractor. "Once we had the first model done, we could do about a unit a day, maybe two, depending on the runs."

Results: Construction on Schedule, Tenants Undisturbed, Zero Floor Penetrations

By implementing SFA Saniflo's above-floor pumped drainage systems, the project team:

• Eliminated all structural slab penetrations — no concrete cutting required
• Maintained occupied office floors — construction continued without disrupting active tenants
• Removed the need for night-shift work — saving significant time and cost
• Overcame stack location constraints — bathroom locations were designed independently of existing plumbing stack positions

"When we filled the system with water and released it, everything worked flawlessly," said the plumbing subcontractor.

With additional project phases already permitted and more than 200 SFA Saniflo pumping units projected for the full build-out, the building owner has confirmed the same above-floor plumbing approach for future redevelopment projects.

"We own another building downtown. There are three bathrooms upstairs, and we're going to do it the same way. We're not penetrating the floors."

Is Your Project Facing Similar Plumbing Challenges?

Whether you're managing an adaptive reuse conversion, a basement renovation, a building addition, or any project where gravity drainage isn't feasible, SFA Saniflo offers a wide range of innovative plumbing solution for residential, commercial and industrial applications.

Explore all SFA Saniflo solutions →

 

Tags: above-floor plumbing, adaptive reuse, macerating toilet, macerating pump, pumped drainage systems, drain pump, commercial plumbing, office-to-residential conversion