The Challenge: To provide a unique take on a common children's museum exhibit experience – a crawl-through tunnel.

The Answer: A Bridge Above!

The DuPage Children's Museum (DCM) expanded four years ago into a renovated 46,800 square foot building in Naperville, IL, that formerly housed a lumber and hardware showroom. It's visible, low-hanging beams and ductwork, along with moderate ceiling heights and a very full exhibit floor can make construction a real challenge. After removal of the previous crawl-through tunnel (never, never put carpeting in a crawl-through for young children!), a new location had to be found for this popular experience.

DCM's core team for this exhibit – Associate Director of Exhibits and Design Peter Crabbe, Play Facilitator Shane Castilo, and myself – worked with fabricator Verne Whiting of Lewellen and Best, Montgomery, IL, to meet this challenge beautifully and functionally through the Bridge Above. Crabbe's design drew inspiration from the local architectural environment – a series of covered wooden foot bridges over the DuPage River along Naperville's well-known Riverwalk. From this starting point, the team created a safe, delightful crawl-through tunnel that is really a covered bridge – with enticing perspectives for the Museum's young visitors high (for them!) above the exhibit floor.

Crabbe's design drew inspiration from the local architectural environment -– a series of covered wooden foot bridges over the DuPage River along Naperville's well-known Riverwalk

Many factors guided the crawl-through tunnel/bridge design – developmental appropriateness, the psychology of the child/adult learning partnership, and, of course, physical considerations. Very young children (the average age of young visitors at DCM is only four) love, and need, to experience the world from a variety of perspectives – from high and low, from inside and outside, from back and forth. These simple, but profound, experiences help them understand how the world and the built environment work. So the crawl-through tunnel experience is developmentally appropriate.

All DCM exhibits are based on the latest early childhood research as well as on visitor surveys and observations by Play Facilitation staff. In this case, both research and observation also told us that it would be very important to our adult visitors to be able to see their children inside the crawl-through at all times. Caregivers need to be able to track children's progress through the structure and know they are safe and happy. Sometimes, the more energetic, and flexible, caregivers crawl right in too! And DCM always encourages that exploring partnership.

Very young children love, and need, to experience the world from a variety of perspectives – from high and low, from inside and outside, from back and forth.

Physical factors that had to be taken into account included: sufficient entry space; turn around areas inside the tunnel; activities in the tunnel that enhanced the educational value but did not create bottlenecks; the need to coordinate this experience with the surrounding theme and "look" of the Build It "Neighborhood;" sufficient sturdiness to withstand the gleeful use of 300,000 visitors; and, finally, the need not to impede traffic flow on the exhibit floor.

To meet the challenge of fitting a structure into these tight parameters, the core team decided to create an enclosed and covered bridge spanning one of the main traffic passages in the Museum. It was a confined space, but just possible. In order to gain the necessary structural integrity to span the distances, yet keep the spaces below open, engineers at Lewellen and Best used two 3" x 10" laminated beams supported by piers made from 6" x 6" columns pinned into the concrete at ground level. The result was two platforms connected in a V-shape with a 7' head clearance that met code and could be installed below the ever-present ductwork and pipes.

The DuPage Children's Museum has won awards for its vivid and engaging architectural colors, the work of design architect Peter Exley, Chicago, IL. The timbers of the Bridge were left natural with a matte satin clear coat so that the soft, warm nature of the wood plays beautifully with its colorful backdrop. Small gusset plates – fabricated from solid core birch plywood and dyed in bright colors – help the Bridge to stand out and yet echo its surroundings. The interior sidewalls of the bridge are lined with 3/8" thick Plexiglas. The open timber frame construction affords a view along the whole length of the Bridge. "Look at me, Mom!" "I see you!" Smiles and delighted chuckling abound as children and caregivers wave to each other. The feeling of exploration and discovery for the children, as well as the feeling of safety for the adults, is evident.

The DuPage Children's Museum has won awards for its vivid and engaging architectural colors, the work of design architect Peter Exley, Chicago, IL.

The exposed wooden, "structural" look of the support beams complements the design of the bridge itself, reflects its Riverwalk inspiration, and carries through the theme of building from the large Construction House next door. Custom steel brackets fasten the uprights, beams and trusses together so the whole structure is extremely stable, though largely free-standing. The team felt this technique provided a better example of engineering principles than tying into the building's existing columns.

The Riverwalk bridges in Naperville also have cedar shake roofs and the team added its own whimsical shingles made of four colors of bright, laminated masonite matching both the surrounding Neighborhood "look" and the gussets. The low ceiling height, the need to ventilate the tunnel and the need to allow sprinkler coverage of the interior prohibited the design team from making a complete gable roof. Instead, the design leaves the top of the 30" wide by 30" high interior of the bridge open with netting stretched over it. This design tactic saved considerable money because the Museum did not have to add more sprinklers either above or inside the tunnel. The 30" width allows children to pass by each other on busy days. At the very end of the bridge, the last 4' opens up to a 42" width so that there is plenty of turn-around space and a cozy place where several young visitors can sit together and admire the views below. There are many engaging vistas of the surrounding exhibit areas, the Construction House, a fish tank, and lots of visitors at play. At strategic points along the crawl, lenses set into the Plexiglas sidewalls give children even more opportunities to play with perspective.

Visitors enter the Bridge Above by climbing a staircase – just like the bridges over the DuPage River. Though this entry method carries through the Riverwalk inspiration, the decision to use a staircase was one of the most difficult of the entire project. The Museum has been committed to accessibility for all children since its inception in 1987 and tries to express that commitment in every design. In this case, however, the only option allowing full access – an ADA compliant ramp – was clearly physically impossible in the space.

Another choice was a climbing tower, often used in commercial locations. The reasons not to use it developed directly out of the Museum's research-based understanding of its young audience and their caregivers. The DuPage Children's Museum is a pioneer in the field's current understanding of how to support the child/adult learning partnership in a museum setting. Based on early research by Piaget, Vygotsky and others, adults can advance their children's learning by just being there to support them as they try out new skills. Not only would a tower access be too challenging physically for a large portion of our age group, the vast majority of adults could not get in it at all. Finally, most of our young visitors actually love going up and down stairs!

With all this discussion behind them, the core team did decide to use a staircase. The treads and risers are standard 7" x 11" format that works well for adults who are used to the configuration and for children practicing "stairs." The design exceeds code on the sidewall of the staircase, making it 48" tall instead of the standard 42". The transparent Plexiglas sidewalls do not cut down on visibility and are positioned parallel to the main traffic flow, tucked into a little used corner. Even the "little used corner" was put to use by creating a storage closet under the staircase for wood and other supplies. The lighted, carpeted staircase has become an invitation for children and their adult partners to veer off the main path and take a rewarding climb to the Bridge Above.

The Bridge Above is a unique and whimsical solution to the challenge of providing a developmentally appropriate crawling experience in a very difficult space. Since its opening in October 2004, thousands of visitors have crawled, scrambled and walked (if they're really little...) through it. And in case anyone wondered, the flooring is linoleum. The design of the Bridge reminds our older, but still playful, visitors of their solidly constructed beloved wooden toys of yesteryear. For our young visitors, its high-up, far-away perspectives and colorful gussets and shingles give the Bridge Above a little tinge of "Oz." eb