The basics of animal shelter design can seem anything but basic. Shelters have unique material and design requirements that are often intimidating to those who don't make their living poring over blueprints. This article demystifies the critical elements of a healthy shelter by investigating ventilation systems, durable flooring, and everything in between.

Whether you're stumped by flooring, puzzled by plumbing, or mystified by ventilation, designing or renovating a shelter can present plenty of architectural adventures. But with the right research, planning, and leadership, you can achieve the goal of a facility that's safe and healthy for both the humans who use it and the animals who pass through it.

The following eight essential elements of shelter design can provide you with a starting point for your project or serve as a planning guide for future goals. But before you jump into the world of air exchanges and epoxy floors, you need a solid plan.

If there are many pieces of the shelter design puzzle, planning is the glue that holds them together. Boards and staff should consider everything from the appropriateness of the building site to the future goals of the organization, experts say.

Some shelters let these things fall by the wayside in the beginning stages of a project. Larry Gates, part­ner at the architectural firm Animal Arts/Gates Hafen Cochrane, has seen this firsthand. "[Shelters will] say, ‘Gee, we need 30 more runs, and we need seven offices,' and they have a very specific idea of what it is they want to build," he says. "But when you really sit down and talk about long-term goals and strategies and direction and what they're trying to accomplish and why they're doing what they're doing, they start getting a little bit fuzzy as to what's required."

Visit other facilities, read up on relevant subjects, and make sure you have a good site for a new shelter before your plans outpace your progress, recommends Scott Learned, president of the consulting engineering firm Design Learned. "We find a lot of people that are trying to jump the gun," he says. "In other words, they haven't checked out planning and zoning and haven't secured a piece of property and they're already designing the building. You need to know where you're going to be first."

Organizations must refine their goals and vision for the future before they can turn to the design details, says Kate Pullen, director of Animal Sheltering Issues for The HSUS. Only after the relevant questions have been answered - what kind of agency the shelter wants to be, which programs will be continued or implemented, and so on - can an agency begin making floor plans and "what goes where" decisions.

When it's time to form a design team, agencies should assemble key staff and board members. "Staff" doesn't just mean the executive director and shelter manager. "When it comes down to ‘Where should we put the outlets?' you want the people who are actually going to be using those outlets to be at that table," Pullen says.

Having a strategic plan completed before taking on a building project will help staff and board members be better prepared to envision the right kind of facility, she says. "Those agencies that are most successful ... have gone through a strategic planning process and keep that plan and those goals in front of them - it doesn't become a dusty document."

1.         Let There Be Light

Don't leave staff in the dark - shed me light their daily duties so they can see what they're doing. Sufficient light can mean different things at different times of the day. "I would recommend having three levels of lighting: a cleaning level, a normal level, and a night-time level," Learned says. "The complaint [from staff] is frequently that they don't have enough light to see to clean. Light fixtures should be gasketed and waterproofed."

Putting the animals in the best light possible is also important, Gates says. "It's really critical to have the adoption areas well enough lit so that people can really see the little black dog in the back of an enclosure," he says.

For brightening the moods of people and animals alike, sunlight can't be beat. "For places where the climate is amenable to it, fresh air and sunshine are wonderful tools to maintain health and sanity in shelter animals and shelter workers," says veterinarian Kate Hurley, director of the Maddie's Shelter Medicine Program at the University of California, Davis. One "fresh air" strategy she suggests is to include "a cat ward that has a window that you can actually open and has a screened-in area where the cats can be exposed to birds and sunshine - sunshine is an incredible disinfectant."

Plenty of window options exist to help natural light find its way into indoor spaces, according to architect Rick Bacon of the Bacon Group, Inc. Clerestory windows, which are placed high on a wall, are relatively inexpensive. Gable-end windows, located on the end of a building, at the "peak," are slightly costlier, he says. Skylights are a common type of window, but they must be properly installed to prevent leaks.

Another useful strategy is "borrowing light," says Martha Seng, an architect with Jackson & Ryan Architects. Light from a room located on an outer wall with windows can reach an adjacent room through windows on an interior wall. That way, "that light goes through one room and into another."

For shelters facing complaints from neighbours or struggling to adhere to local noise regulations, Learned recommends careful placement of windows. In these situations, he suggests installing windows constructed of double-paned thermal glass with a low emissivity rating. Because the sounds escaping from skylights are directed toward the sky rather than toward the noise-complaint neighbours, they offer an advantage over windows set in walls, Learned says.

Window glass with a "low-e" rating is a must, says Learned - it means the glass can lessen the heat effects of the sunlight and also help a building retain heat on cold nights. When selecting windows, price is often a good general measure of quality, he says: "Buy well - buy the best you can."

2.         Don't Strain Your Drains

Investing in good plumbing is anything but money down; in animal shelter it can be the opposite, saving you big bucks if you install a system that can handle all the dirt, grime, and hairballs that come its way.

Animal facilities have unique plumbing require -. "The standard [drain line] size is four inches, and in other types of buildings, that's just fine," Seng says, "but plumbing is a tremendous factor in animal shelters. Both the supply lines and the drain lines are used con­stantly and there's always the hair factor. So it just makes sense to make those lines a little bit bigger ... We always recommend nothing less than six inches in a shelter."

With large drains, drain covers are a necessity - for example, to prevent tiny puppies from becoming trapped in them. Bacon's choice of materials depends on his clients' budgets; he uses his favourite, stainless steel, for those with more to spend, and PVC or galvanized steel for those who have fewer funds to spare.

While most architects would probably agree on drain size and drain covers, the issue of trench drains versus individual drains generates more debate. Gates believes trench drains can be tricky to completely clean and disinfect, but Bacon usually avoids individual drains partly for the same reason: he's heard many complaints from shelters about the precision required to direct all the water in a run into the "little target" the individual drain creates. And contractors face difficulties when installing them, he says.

But trench drain installation isn't a piece of cake either - and an improperly installed trench drain can do more harm than good, says Pullen. "If they don't flow right, you have water backup and that water is diseased water, and you could have animals drinking it. ... I think ideally if you have the budget, you should do individual drains, but trench drains properly done - and large enough - certainly work fine."

If individual drains aren't in your budget, says Seng, you can also try to group the drains. "We've done it where we've had one drain that's kind of at the junction between four kennels where the walls meet," she says. "And that works pretty well."

Bacon offers another strategy: installing trench drains in the individual runs, rather than a continuous drain that stretches from run to run. This way, germs still left over following scooping and cleanup don't pass from one dog's area to another. "That helps in odour and disease control," he says.

As for "human" plumbing needs, Learned recommends positioning hand-washing sinks between zones of the shelter - between two kennel areas, for example - to encourage employees to wash their hands between handling different sets of animals. (Although HSUS experts recommend that staff wash their hands after handling each animal in the shelter, they recognize this practice often isn't possible - except when it becomes absolutely necessary during a disease outbreak. For routine cleaning duties, hand sanitizers can offer a less effective but easier alternative for hurried animal care staff.)

3.         Focus On What Lies Beneath

From scratching paws and tramping feet to hot water and corrosive chemicals, flooring in an animal shelter takes a beating. Seng likes MMA flooring (methyl methacrylate), which can "cove" or wrap up the side of a wall. "It's the most expensive, unfortunately, but it does last the longest; it's the most durable ..." she says. "It holds water from penetrating the walls or the floor. It's also very forgiving in a structure that may have cracked slabs; it can span over a crack and it does have some flexibility with movement.

That flexibility isn't found in epoxy floors to the same extent, Seng says.  "If the slab is cracked, that crack will usually translate through to the flooring material... [And] if you have a bad installation, it's going to be a bad floor. It's very much dependent on the installation ability.

While Learned agrees with Seng that proper installation is critical - the underlying surface must be prepared carefully and be entirely clean and dry - his pick for the best flooring is a two-part epoxy floor.

Learned emphasizes that epoxy flooring shouldn't be confused with less durable epoxy paint. "A two-part epoxy flooring system is made from the combination of pigmented resin-based component and a water soluble hardener," he says. "This material is rolled or towelled onto the subfloor to a thickness of 3/8 inch.

Because this flooring isn't porous, bacteria find it hard to get a foothold - and epoxy floors are easily disinfectable and available in several colours, he says.  "A few years ago all you could get was this kind of orange plastic that you used to see in commercial kitchens - and you still do see in commercial kitchens," he says.

Learned puts more stock in the durability and flexibility of epoxy floors than Seng does.  "Once these things are in place they'll seldom crack, they have a pretty good flexibility, they can be coved up the wall... So you get this incredibly smooth, sealed, washable surface."

The practice of coving a floor up a wall - up to 16 inches or so - doesn't just improve cleaning; it also enhances disease control, says Learned.  The junction where a wall meets the floor can provide a great hiding place for pathogens and moisture. Coving doesn't let that happen, he says.

From least to most expensive material as ranked by Gates, flooring can range from stained sealed concrete to poured epoxy or poured acrylic floors to porcelain tiles with epoxy grout. "[The last one] is a great material, because if repairs are necessary or changes are necessary, you can take out individual tiles. ... You can also specify the tiles with exactly the type of slip resistance that you want to have. And any poured floor you can't do that with."

For non-animal areas - conference rooms, for example - Gates recommends vinyl tiles. But tile can pose problems in areas that house animals, says Bacon. "I kind of shy away from tile in animal housing areas because of the number of joints in the tile that they have to clean. ... You can get huge tiles, like 18-inch by 18-inch tile, but you'll still find it's not as conducive to cleaning as [other materials]."

4.         Reduce The Sound And Fury

The shelter will never sound like a symphony, but it doesn't have to sound like a doggie metal band either  Choose carefully when hiring the person who will design your shelter's acoustic features, says Learned. "This is one of those cases where I would say it's important to hire somebody who has experience in acoustic design in a wet environment. ... A lot of the products and surfaces are not well suited to the environment."

Both Bacon and Seng recommend Pyrok, an acoustical plaster that can be applied to walls and ceilings to help improve sound absorption. Pyrok can be combined with other methods of reducing noise, Bacon says. One method in effect creates two ceilings - one that is exposed and another which is above that ceiling. "So ... what's not caught by the acoustical ceiling is caught by the second - the false ceiling above it, where we put the Pyrok," he says.

Bacon suggests other strategies, such as dividing animal housing into smaller sections, and using vestibules to make it more difficult for sound to directly travel to an adjacent room if the door is open. The proper wall design can also help to reduce sound.

Carefully selected ceiling materials can help, too, Seng says: "We also recommend acoustical ceilings in kennel areas, and you have to use a special ceiling tile that has a kind of a ceramic membrane that keeps bacteria from growing and moisture entering into the ceiling tile."

Gates' strategies for reducing noise with structural elements include sound-soak panels, ceiling baffles, and other sound-absorbent materials. Floating soffits can help, too; sound is deflected off the walls to the area between the soffit and ceiling, where it remains.

Don't let your mechanical systems become accomplices to noise problems, Gates says. "If you have a mechanical duct that goes from sound zone to sound zone, it'll act just like a megaphone and transfer sound from one area to another."

Agencies that are worried about sound being transferred to adjacent residential areas can invest in outdoor barriers. "Barriers for outside acoustic control need to be fairly tall because of the wavelengths in question-and fairly massive," says Learned.

5.         Follow your own clean air act

Air is so invisible and so pervasive that we take it for granted; there's a reason the phrase "it's like breathing" is synonymous with "it's easy". But maintaining indoor air quality is such a complicated affair that ventilation systems make up a major part of the budget for a new facility.

And one of the most important things to consider is air exchanges.  The HSUS recommends at least 12 to 15 air exchanges per hour. Seng agrees, while acknowledging the high energy consumption that these conditions produce. New technology in the form of energy-efficient units can help, she says. For a shelter with air conditioning, the cooled-down "used" air that's exhausted from inside the building can then be used in a different way: to lower the temperature of incoming air. "It's kind of a neat concept where you make use of the temperature of the air that you're exhausting," Seng says.

Proper "pressurization" will help keep disease and odours from spreading. When the air pressure in a room is negative com­pared to other areas, air will flow into that room. A room with positive pressure will bring about the opposite effect.

The kind of pressure required in a given area will depend on the function of the room. "We want positive pressure in something like a spay/neuter surgery so you're pushing the contaminants out," says Gates. "And you want negative pressure in an animal area, so that the odours are being pulled into the animal space and exhausted and not going out through the rest of the facility."

A facility should be separated into zones, says Learned, and the more zones the better. "When I'm talking about zones, I'm talking about thermostats on the wall," he says. "The worst building is one that has one zone for the whole building, and air is being moved from one area to another, and animals are get­ting sick and the control of heating and cooling is pretty poor."

For budgets that allow it, veterinarian Hurley recommends maintaining cleaner air by housing fewer cats per room; this strategy will reduce the number of par­ticles in the air. "If you're going to invest in ventilation, which is quite costly, and a significant ongoing cost as well ... maybe it would make sense to build a bigger building with fewer cats per square foot and save money in the long run on your ventilation," she says.

With all of the funds that will likely be spent on air systems, the cat areas must reflect that, Hurley says. "If you have two traditional banks of cat cages that are closed on three sides, with just an open front, the middle of the room may be very, very well ventilated. But at the cat's nose, which is where it counts, you probably have much fewer air exchanges." One option that exists, Hurley says, is to allow the backs of the cages to have air routed through them in addition to the fronts.

6.         Bring Out The Welcome Wagon

Think of your lobby as your public face - and your best chance to make a good impression on people who may never have entered a shelter before. "What you want somebody to do when they walk through the front door is say, ‘Wow, this is a really nice place,' instead of saying, ‘Oh my God, it smells, I can't hear myself think. I'm out of here-now,' " says Gates.

A welcoming lobby should be bright, clean, and odour - free, says Seng. The graphics should be easy to understand so that visitors will feel well-directed, and educational materials should be abundant. Visitors should be able to find places to sit and should feel comfortable there.

Creating that comfort zone involves careful placement of the front desk, Bacon says. Visitors shouldn't find themselves directly in front of the counter as soon as they walk in the door. "We've been finding that people need to have a space to come in, see what's going on, and then walk up to the counter instead of just [a setup where they] walk in the doors and they're there."

After visitors get their bearings, they shouldn't have to look far to see animal areas, Seng says. "We always like to have as many glimpses of animal holding areas off of the lobby as possible," she says, "so that when people are in there taking care of business, they're always aware that they are in an animal shelter."

While comfort and aesthetics are important, technical or practical details shouldn't be lost in the big picture.  Learned advises shelters not to forget that the lobby is an animal area as well as a human area -  for example, it might be a good idea to install a floor drain to aid easy cleanup. Electrical outlets should be placed at least four feet high, he says - not on the floor. "It's only going to take a few minutes for a dog to urinate on the floor receptacle and you're going to have a ... problem," he says.

To avoid giving the wrong impression, the lobby should occupy the middle ground between uncomfortable and lavish. "If it's too big and grand, then I think there's a perception that money is being wasted that could be better spent on the animals," Gates says. "So I think it has to bear some really direct relevance to the size of the shelter and what's trying to be accomplished."

Regardless of the size of the facility, most agencies can separate their relinquishment and adoption functions, even if they can't have two separate entrances or two separate staffs. Pullen suggests separating an area that has a single desk by using a wall down the middle of that area, essentially dividing the desk, and directing visitors where to go. This way, a potential adopter won't be able to get her heart set on an animal who can't be put up for adoption, and as Pullen says, "it helps keep people focused."

7.         Create Cosy Canine Quarters

The public will focus the most on your adoptable housing areas. But shelters should be careful not to let areas for newly admitted animals become nightmarish places, Hurley says. Studies have suggested that dogs who have been severely stressed may later be prone to such behaviour issues as separation anxiety, she says. "It's a waste to put them in... palatial quarters for three months of their stay but they had to get through that hellish week in a really scary, really noisy place where they didn't have a crate or any place to hide.

With facing kennels, dogs often can't escape the sight of their across-the-aisle neighbours, and barking matches can ensue. Seng suggests placing a low wall between rows of animals to block the view.

Seng and Bacon suggest group housing of dogs in certain cases, but Pullen urges caution when considering this arrangement. Companions or litters should be housed together, as long as mixed-sex pairs or groups are spayed and neutered or are under the age of sexual maturity, she says. "When animals who are not companions and not from the same litter are grouped together, then health screenings, sanitation, disinfection, and observation must be 100 percent or there will be major problems."

"When you have a single puppy left from a litter that's healthy, sometimes matching that puppy with a more mature, healthy dog that will act as a teacher and keep the puppy in line - and making sure that they get along - is fine," says Pullen. But she cautions against making this housing arrangement routine and letting it get out of hand. I think that if we go into this business saying we can always double up or triple up or quadruple up - we used to call that overcrowding, and it still is in my opinion."

The danger lies in the fact that both the added ease of cleaning and the potential stress-relieving benefits offered by a run divided by a guillotine door are negated when shelters regularly close the door and house one dog on either side. To do this opens a can of worms, Pullen says. Cleaning becomes inefficient, as staff can't temporarily move a dog to the other side of his run if it is already occupied by another dog. Without sufficient hands to walk dogs while the cages are cleaned, staff often tie dogs to cages, resulting in nose-to-nose contact with neighbours. And letting the disinfectant sit on the surfaces of each run for the proper time period becomes next to impossible, Pullen says.

"When we start seeing health problems, overcrowding problems, disease problems in a shelter, it's often because that organization has shut the guillotine door and housed animals on both sides," she says.

Double-sided runs not only aid in cleaning but allow dogs to separate daily activities like eating and elimination. "It does make me sad to see shelters built with single-sided runs for dogs unless they're really confident that they have such a great volunteer program that those dogs are going to get out and get walked and not have to go potty in their runs," says Hurley.

In the adoptable areas, animals can benefit from what Seng calls a "retail trick." "We like to put animals behind glass [because] when you can't touch them, they become more desirable."

Though effective, glass should be used judiciously. A shelter that uses glass everywhere in an effort to show the public it has nothing to hide may be doing a disservice to both the animals and the public, Pullen says. Having quarantine wards and court-case holding areas on view can be counterproductive. "Not every animal we handle is adoptable. Our goal is to adopt our adoptable animals, so let's keep the public's focus on those animals rather than the ones that at this time are not considered adoption candidates." That can be done by having only the adoption areas visible to the public; Pullen recommends keeping some animal areas off-view and accessible only to citizens accompanied by a staff member.

8.         Ensure Equal Rights For Cats

Dogs may have a tough time adjusting to their temporary shelter life, but cats are even more at risk - in part because of their nature. Cats in the shelter can't realistically be taken out for walks, and they can't make jungle-leaps to countertops when feeling threatened.

Hiding places, perches, and safe spaces for outside exercise can make a significant difference in making cats - and other shelter animals - feel more at home. "The kind of number-one goal in trying to reduce stress," says Gates, "is to provide a variety of environments or the ability for [animals] to kind of choose their environment a little bit. It's that lack of choice that is the number-one stressor for captive animals."

Hurley agrees. "A lot of shelters don't want animals hiding because then they won't get adopted, but then on the other hand, if they're wanting to hide and unable to do so, they're going to be so stressed that their behaviour may not be very appealing anyway."

Although elements like kitty perches can assist in a shelter's attempts to create a feline comfort zone, they can't compensate for poor housing setups.

Noting the disparities between the quality of housing for cats and for canine shelter residents, Hurley says, "They deserve at least as good housing as dogs." She worries that the typical single compartment box cages are harming cats, especially recent arrivals. "At the time they are most stressed out, most vulnerable to disease, most likely to be infectious and infected, before vaccines have had time to take effect, before you've had time to test them for disease, before you've had time to spay and neuter them and just help get it together-that's when they're crammed [into] a box cage."

Stress in cats isn't as easy to observe as stress in dogs, Hurley says. "[With] dogs, it's obvious, when they're scrambling, when they don't have enough space and they're freaked out and they're barking, and a cat just lays there quietly and develops a respiratory infection."

Some of that stress can arise during the cleaning of single compartment cat cages, says Hurley. Cats are often placed into cat carriers until they can return to their newly cleaned cages. "To take a cat that's already in a new scary environment and put it in a carrier every single day ... staring at other cats, that's very stressful."

Disease transmission can be a major problem when cats are temporarily transferred to other cages while theirs are being cleaned, Hurley says. "If you clean one cage and then put a cat in it, [moving] it from another cage, studies have shown that just moving cats from a cage to a new cage is sufficient to activate feline herpesvirus infection," she says. "So you're guaranteeing that you're activating upper respiratory infection in a good percentage of your new intake cats, just by moving them from cage to cage."

When a double-sided cage setup is used, a cat can be kept on one side of his cage while staff clean and disinfect the other, Hurley says. If this sort of cage isn't feasible, shelters can place feral cat boxes inside large single cages, she says - cats can go into them while their cages are cleaned and the boxes can be regularly cleaned as well.

Limiting the number of cats per housing area can help control disease outbreaks and noise, says Hurley. "If you could have the choice between building ten rooms with five cats each, that would be much, much better than building one room with 50 cats."

Housing fewer animals per room can also make it easier for air systems to do their job, Pullen says. In her travels she has seen shelters with new air exchange systems housing as many as 50 cats in one cramped space. "And everybody's asking, ‘Well, why do we have these sick cats?' Well, the reason you have sick cats is that the air exchange can't keep up with recycling fresh air," she says. "The minute they cut the population to 25 or 30, the illness goes away because the air exchange can compensate."

Hurley believes that shelters need to recognize infectious disease as not only a physical issue but a mental health issue for cats. "Infectious disease control in cats is the single most important thing we can do for them behaviorally and in terms of their well-being, because if they get sick in the shelter, many of those infections are chronic and it means isolation for them. ... If you design your shelter to not take into account feline infectious dis­ease control, you're never going to be able to take really of cats".

HSYS Recommendations for Isolation and Separation

Animals in the shelter should be separated in the following ways:

Ø  Dogs from cats

Ø  Sick or injured animals from healthy animals

Ø  Weaned puppies and kittens from adult animals

Ø  Males from females (especially those in season)

Ø  Aggressive animals from all other animals

Ø  Nursing mothers and their young from all other animals

Facilities should contain the following five areas to isolate and separate animals with different needs and conditions. These methods of isolation and separation will promote animal health, protect the public, protect the agency from liability issues, help staff make adoption and euthanasia decisions, and allow the agency to present only adoptable animals to the public.

Receiving Area: All incoming animals should be triaged in the treatment/ receiving room on the day they arrive. After staff have examined an animal and possibly administered vaccinations, the animal moves to one of three areas: "healthy hold," quarantine, or isolation.

Isolation Area: To keep the general population healthy by preventing the spread of disease, this area houses incoming sick animals who require a stray holding period or animals who become sick while at the shelter.

Quarantine Area: This area houses animals being observed for bite/rabies quarantine.

Healthy Hold Area: This area allows healthy animals time to acclimate to the shelter and gives staff the chance to further evaluate them. Incoming animals who are not sick should be held in the dog and cat healthy hold rooms for at least two days. If an animal becomes an adoption candidate based on her health and behavior, she may be moved to the public adoption area after this time. Healthy but aggressive stray animals can be housed in healthy hold for the stray period as well.

Adoption Area: This area houses healthy, behaviorally sound animals who have been transferred from the healthy hold area and are available for adoption. This housing area is the only one that should be accessible to the public without a staff escort.