100x120 Indoor Sports Facility

The estimate at 100x120 moves with four computed quantities: 12,000 square feet of floor, 440 feet of perimeter, 6,160 square feet of wall and 12,369 square feet of roof. Everything else is site and specification. Two operations of the same size can want opposite plans, so the arithmetic below is a starting point rather than a recommendation.

Floor treatments, power distribution, ventilation to the fitted area and its finishes carry a cost per square foot well above the open floor's, so the split between the two moves the estimate more than the total area does.

• clear height set by the most demanding activity
• the clear span and how the floor subdivides
• zoned lighting and control
• equipment storage rooms opening onto the floor

This page is ordered around fitted and support space, because every square foot committed to equipment or rooms is floor that can no longer be rescheduled.

The footprint holds 6 training zones — 3 across by 2 deep — and leaves 26 feet of depth for a fixed equipment area with its own floor treatment, separated from the open activity surface it serves.

What distinguishes 100x120 is depth behaviour: 2 rows along 120 feet after 14 feet of circulation, with 26 feet unaccounted for at the end of the run. Whoever operates the building daily should read the plan before it is frozen, because they know where the pinch points are.

A 100 by 120 footprint is a mildly directional plan: 12,000 sq ft enclosed by 440 ft of wall, at a 1.2:1 length-to-width proportion. Along its 120 ft dimension it takes 3 runs of training zones at 40 ft, leaving 0 ft over — the 0 ft is where the argument about this size actually happens. Fixed equipment converts flexible floor into committed floor, and that conversion is irreversible in practice. The planning judgement is how much of the building's area should be permanently assigned and how much should stay open for whatever is scheduled next. A sports building's real capacity is set by its schedule and its changeover time, not by its floor area.

At 100x120 the operating question is a specific one: how much of this floor becomes permanently fitted, and what does that do to the open surface that remains? That is a different question from the one a indoor sports facility of another shape has to answer, and it is why this footprint is planned as a facility combining an activity floor with fixed training and conditioning areas rather than as generic covered area.

The programming pattern this floor could equally be scheduled as is a continuous turf-style floor planned as one uninterrupted surface: there is no end storage, so equipment stands at the edge of the surface and reduces the usable field. Dividing the 12,000 sq ft by the 30 by 40 ft training zone gives roughly 6 positions before circulation is deducted a second time for cross movement. Whether the plan keeps 6 or drops to 3 comes back to the question this footprint is really answering: how much of this floor becomes permanently fitted, and what does that do to the open surface that remains?

Depth arithmetic leaves a working end zone here. 2,600 square feet sits past the last row, which is why 100x120 tends to be planned with a fixed equipment area with its own floor treatment, separated from the open activity surface it serves designed in rather than added later. Daylight placement changes how a floor is used far more than its cost suggests.

Spare width is the more valuable of the two leftovers here: a continuous 10-foot strip beats the same area stranded at the end of the run, because it touches every position along the way. Security and after-hours access are easier to design in the door layout than to bolt on later.

At 1.2:1 the plan is close enough to square that neither width nor depth is doing the arguing; what decides the layout here is where the openings go, because no proportion is forcing a direction on the floor. Spent as a square 110 by 110 instead, the same 12,000 sq ft would stand 3 training zones across rather than 2, and would trade this plan's length for parallel access. That is the width-against-depth decision this footprint has already made. A building of this size behaves like a small yard under a roof: zones need to be defined, signed and left alone, or they migrate. The longest internal travel on a 100 by 120 plan is about 156 ft corner to corner, and the shortest useful one is the 100 ft cross-run. For a a facility combining an activity floor with fixed training and conditioning areas that matters where fitted training area sits, because shortening the 100 ft run to serve it lengthens every trip along the 120 ft dimension. Changing, restroom and waiting provision is sized against concurrent groups; provisions for the specific building are determined by the local authority. That movement pattern, not the 12,000-square-foot total, is what decides whether the leftover 26 feet is useful here.

Nominal bay division computes to 5 bays at about 24 feet, narrower than the 30-foot module — so frame lines land inside positions and the interior has to be set out from the columns. The span is the commitment; everything inside it is rearrangeable later, and the 100-foot dimension is not.

Two-plus rows change the access question entirely. Every rear position at 100x120 needs either its own opening or an aisle, and 10 feet of spare width is what that aisle has to come from. Doors and their approaches decide more about daily use here than the enclosed area does.

Extension is cheapest along the 120 ft dimension, where each added bay repeats work already framed; widening past 100 ft is a different frame rather than a longer one. Growing to 100 by 160 adds a 4th run of training zones — useful if the constraint is training zones rather than the 0 ft already spare at the far end.

Configured as a facility combining an activity floor with fixed training and conditioning areas, 100x120 is judged on whether the 6 training zones it holds match the operation, and on whether the 10 feet of spare width leaves the route this mode depends on.

• Does the work need an interior street with independent zones on both sides and turning room at each end, or does it need a second lane that this 100-foot span cannot give?
• Is the 120-foot length being bought for depth, or for the repeated bays — a long repeating bay sequence, so segment boundaries are set by bay lines rather than by walls?
• Which sport sets the clear height, and does every zone meet it?
• How does the floor subdivide, and does the structure allow the dividing lines you want?

The 100-foot gable can carry 3 openings, one per training zone, with 10 feet of wall left for piers between and beside them — the arrangement that keeps each position independently reachable. The floor treatment is a use decision that outlasts most of the equipment standing on it.

The fitted area benefits from its own entrance, because it is used at different hours from the scheduled floor. Equipment delivery needs a route that does not pass through either.

Span drives headroom at 100x120: 100 feet of width on a 3:12 pitch puts 26.5 feet over the middle and 14 feet at the walls, so where a tall item stands matters as much as how tall it is. The building is fixed for decades while the operation inside it changes every few years, and the plan has to survive that.

Height on a 100 ft span is a separate decision from the 120 ft length, and it is the span that sets the frame's behavior. Raising the eave over 12,000 sq ft affects every bay along the 120 ft dimension, so the test is whether fitted training area genuinely needs the extra clear height or only the floor area.

Ventilation across 12,000 square feet at this height: sustained high activity across a large volume, so air handling is sized for the busiest scheduled period.

• 60x80 moves the count from 6 to 0 training zones (1 across by 0 deep), which is the reason to choose between them.
• 40x120 moves the count from 6 to 0 training zones (0 across by 1 deep), which is the reason to choose between them.
• 50x100 moves the count from 6 to 0 training zones (0 across by 0 deep), which is the reason to choose between them.

Because this footprint is planned as a facility combining an activity floor with fixed training and conditioning areas, the useful next reads are different from the ones a differently shaped indoor sports facility suggests: fitted training area, committed versus open floor, equipment zone separation.