Plumbing for Pets—and Vets

Although it may surprise many engineers, veterinary hospitals are undergoing a transformation from neighborhood "mom and pop" facilities into specialized referral centers that resemble hospitals at teaching institutions. With the increased sophistication come bigger challenges for architectural and engineering teams to design better and more efficient facilities.

By RAMZI Y. NAMEK , P.E., Associate, Siegel, Rutherford, Bradstock Ridgway Inc., Baltimore, Md. October 1, 2000

Although it may surprise many engineers, veterinary hospitals are undergoing a transformation from neighborhood “mom and pop” facilities into specialized referral centers that resemble hospitals at teaching institutions. With the increased sophistication come bigger challenges for architectural and engineering teams to design better and more efficient facilities.

Designing the plumbing systems may be the greatest challenge for mechanical engineers. The equipment used by veterinary surgeons needs water connections, drainage, medical gases and some uniquely specified plumbing fixtures. Certain areas, such as dog runs, are sources of objectionable odors and diseases if not properly sanitized and drained. Other relatively new fields, such as animal dental care, require extensive plumbing.

Hospital and plumbing needs

According to a recent article in Veterinary Economics , about 40 percent of veterinarians claim that problems arising from plumbing system failure is one of their major headaches. This is not limited to tangible failures such as pipe leakage or water-heater rupture; it also includes psychological factors such as objections to unpleasant odors resulting from poor sanitation. Causes of plumbing system failure include higher concentrations of gases and particulate matter, the extensive use of plumbing and medical gas piping throughout the facilities and the fact that many of the specified fixtures are unique to the facilities and designed to operate under specific constraints. Also, many engineers have little experience designing veterinary hospitals and either underdesign or overdesign the mechanical systems.

The best way to avoid plumbing-related headaches is to become familiar with basic layouts of modern veterinary hospitals and the functions associated with each space, which include: Reception areas and waiting lounges; records and filing areas; examination rooms; treatment rooms; preparation areas and scrub rooms; surgery rooms; laboratories; x-ray and darkroom facilities; pharmacies; isolation wards; hospital bathing areas; dog runs; and typical support spaces such as staff rooms, doctors’offices, laundry rooms, multipurpose equipment rooms, janitorial closets and storage areas for vacuum and oxygen bottles. Some specialized facilities have spa therapy rooms with either an indoor spa or outdoor pool for post-surgical aquatic treatment. Table 1 (opposite) shows a breakdown of rooms and associated equipment types, as well as the supply- and drainage-connection requirements.

Another fast-growing field is animal dental care. Some facilities specialize in this service while others integrate it into overall hospital services (see “Baring their Teeth,” page 34).

Some of the “must-do” items for today’s types of veterinary facility include:

For veterinary hospitals, certain types of equipment are frequently specified and should be noted by design engineers (see “A Dog’s (Medical) Life,” opposite). Commonly employed types include tub tables-also known as wet tables-flushing floor drains, steam and gas autoclaves, “therapy spas,” solids traps, hair traps and heating pads. Wet tables are generally served by hot- and cold-water connections, a cabinet housing a water-filter canister, a filtered water supply and water-connection valves with circulating pumps and traps.

Also common are rooms for use as “dog runs” or kennel boarding, which can be indoors or outdoors and require fresh potable water supplies, drainage and high levels of ventilation and sanitation.

Exam and treatment

Inside a typical hospital, examination rooms allow for preliminary diagnosis of animal patients, and may require a sink. The treatment room is the heart of the facility, where procedures are carried out and where an intensive-care unit may be set up for animals recovering from surgery or treatment. Treatment rooms should be furnished with countertop sinks that are integral with the working tables, and at least one tub table should be provided depending on the hospital’s size. Also needed are outlets for piped oxygen and vacuum, typically no fewer than two outlets by the walls adjacent to treatment tables. At the Anne Arundel Veterinary Emergency Center in Annapolis, Md., for example, post-treatment cages are racked along the perimeter of the treatment room with one oxygen outlet for each four cages.

In modern facilities, treatment rooms are designed as working areas open to the laboratory, x-ray, pharmacy and surgery scrub rooms, each of which has a sink. For hospitals with special treatment rooms for more serious cases, a tub table, sink and oxygen and vacuum outlets are typically needed.

Sinks are also provided for food preparation areas , dark rooms and staff rooms . Hospital bathing and dog-grooming areas should have sinks and elevated tubs that come in 4-foot or 5-foot dimensions as needed; pressure-assisted faucets are recommended. The flooring specified should be smooth, nonabsorbent, skid proof and resistant to detergents and solvents.

The surgical suite consists of a scrub room that opens up to one or several surgery rooms. The scrub room should have a surgical sink with an electronically activated gooseneck-spout faucet, a countertop sink and a separate washer and dryer.

While some designers recommend piping vacuum to all rooms in a facility, the surgery room should have piped oxygen, vacuum and compressed air. Two sets of outlets of each gas should be piped above the ceiling and dropped over the surgery table to facilitate connection to anesthesia machines and respirators. Most hospitals use isofluorane in cartridges for anesthetizing purposes and portable nitrogen bottles to power surgical tools. No sinks or floor drains should be installed in the surgery room; again, floors should be smooth, nonabsorbent, skid proof and resistant to detergents and solvents.

Oxygen tanks should be stored in rooms with an access to the exterior. In larger facilities where oxygen usage is high, the payback from an in-house oxygen generator is very short as compared to bottle delivery. The air compressor and vacuum pump serving the hospital should be stored in a well-ventilated room accessible to the exterior. The multipurpose storage rooms should have at least one lavatory, a janitor sink and a washing machine with a dryer for general hospital laundry. An optional laundry sink may be installed. Finally, water closets, lavatories, urinals and outdoor hose bibs should be included to meet codes.

Plumbing dog runs

Dog runs require particular attention because large animals are housed for long periods of time in rather small constraints, and regular washing and draining of the rooms is critical to mitigating the spread of disease and odor. The plumbing design of dog runs is based on the quantity of dogs housed: A class-I room usually is for one to five dogs, a class-II room houses six to 10 dogs and a class-III room is designed for more than ten dogs.

  • drainpipes are connected above the finished floor; the main drain is trapped and dropped to sanitary piping below the slab.

  • Sometimes, a 4-inch drain with a grate cover may be located in the center, towards the back of each cage, but most grates do not allow larger solid waste to pass through, and the amount of drainage piping below the slab may be excessive. Alternatively, the floor may be sloped to a trench drain offset to one side of the room in front of the cage entrance; the trench slopes to a drain that is trapped and connected to sanitary piping below the slab. It is highly recommended to use a flushing floor drain.

  • em effectiveness. Some designers have employed a trench installed inside the cages towards the back, but the animals may be able to enter the trench, leading to cross-contamination or the spread of disease. In this case, a sleeping bench above the trench area is suggested.

General rules for drainage systems for dog runs include:

Out of the ordinary

Some hospitals feature special treatment pools or spas that are used for sessions of up to 90 minutes at water temperatures of about 92° F and chlorine levels similar to those for human use. An adjacent freshwater hose-spray station is used to rinse the animal, and tempered water is preferred.

While therapeutic spas are out of the ordinary, they demonstrate the extent to which plumbing-system design impacts newly constructed veterinary hospitals. Mechanical engineers must be aware of every room’s needs and how to design a reliable and economic system.

Table – Plumbing Specifications for Veterinary Hospital Equipment

RoomFixtureDomestic cold waterDomestic hot waterDrainOxygenVacuum/suctionComp. airRemarks
Treatment room Tub table 1″ 1″ 3″ yes yes yes With hot water



Countertop sinks 1/2″ 1/2″ 2″
Lavatory 1/2″ 1/2″ 2″
Medical gas wall outlets yes yes
Exam room Countertop sinks 1/2″ 1/2″ 2″ Optional
Dog run Flushing floor drain 3/4″ 4″ Highly


Hose wash assembly 3/4″ 3/4″
Wash tub 1/2″ 1/2″ 2″ With hair trap
Surgery prep & scrub Scrub sink 1/2″ 1/2″ 3″ With gooseneck spout
Countertop sink 1/2″ 1/2″ 2″
Laundry for surgery gown 1/2″ 1/2″ 3″
Surgery Medical gas wall outlets yes yes yes
Laboratory Countertop sink 1/2″ 1/2″ 2″
Pharmacy Countertop sink 1/2″ 1/2″ 1/2″
X-ray and darkroom Developing machine yes yes Check sizes
Isolation ward Floor drain 3″
Hose wash assembly 3/4″ 3/4″ Optional
Special treatment


Countertop sink 1/2″ 1/2″ 2″
Tub table 1″ 1″ 3″ yes yes yes
Storage rooms Steam Autoclave yes Distilled water
Ethylene Oxide gas sterilizer Check codes
Multi-purpose laundry 1/2″ 1/2″ 3″
Floor drain 3″
Oxygen bottles & generator yes yes
Vacuum pumps yes Check codes
Janitor closet 3/4″ 3/4″ 3″
Lavatory/sink 1/2″ 1/2″ 2″ With hair trap
Autopsy table 3″
Wash tub

Air compressor

1/2″ 1/2″ 2″ With hair trap
Dental suite Tub table 1″ 1″ 3″ yes yes yes With HWC
Countertop sinks 1/2″ 1/2″ 2″ Solids/plaster


Medical gas wall outlets yes yes
Special treatment Spa Check manuf.

& local codes