Building Types
80x100 Hay Barn
- Width
- 80 ft
- Length
- 100 ft
- Floor area
- 8,000 sq ft
- Perimeter
- 360 ft
Use
How a 80×100 Hay Barn May Be Used
Equipment shelter
Machinery clearance height and door width are usually the limiting factors, not floor area.
Commodity and forage
Bulk storage depth against the sidewalls affects how the building is loaded and unloaded.
Drive-through access
End-to-end access lets equipment pass through without reversing.
Seasonal working space
Open floor is commonly kept for repairs and staging between seasons.
Example
Example Configuration
Quick dimensions
At a Glance
Width
80 ft across the gable end.
Length
100 ft along the sidewall.
Floor area
8,000 sq ft of clear floor.
Eave height
20 ft at the sidewall on the stored profile.
Configuration
How This Building Is Configured
Configuration summary
| Building type | Hay Barn |
|---|---|
| Footprint | 80 ft × 100 ft |
| Floor area | 8,000 sq ft |
| Eave height | 20 ft |
Planning
Footprint & Space Planning
Footprint
Width and length are chosen together: width is usually fixed by what has to fit side by side, length by how many bays are needed.
Height
Eave height affects door options, storage height and how open the interior feels.
Access
Where vehicles and people enter changes the whole interior layout, so access is settled before anything else.
Doors and openings
Opening width, height and position are specified with the supplier; they affect the frame and the wall bracing.
Site
Slope, drainage, access for delivery and erection, and the foundation are confirmed for the actual property.
Expansion
Extending along the length is usually simpler than changing the width later, which is worth deciding up front.
Access
Doors & Access Considerations
Opening width
Across a 80 ft gable end, the practical opening width is limited by the frame and confirmed with the supplier.
Opening height
A 20 ft eave sets the ceiling on door height before any frame change.
Drive-through
Matching openings at both ends avoid reversing, at the cost of usable wall.
Similar sizes
Other Sizes for a Hay Barn
80′ × 80′
6,400 sq ft
80′ × 120′
9,600 sq ft
70′ × 100′
7,000 sq ft
Related
Related Building Types
Example configuration — for planning purposes only.
FAQ
Common Questions
80 ft × 100 ft is 8,000 square feet of floor area before any interior partitions.
Length is usually adjusted in bay increments, and width is a larger design change. Both are confirmed with the supplier for the final design.
Site preparation, foundation and erection are commonly quoted separately from the building package. Confirm the scope of any quote you receive.
Compare nearby sizes
Related footprints for this building type
Each page works through one footprint for one building type.
Cost drivers
Quantities that move the estimate at 80x100
The estimate at 80x100 moves with four computed quantities: 8,000 square feet of floor, 360 feet of perimeter, 7,200 square feet of wall and 8,433 square feet of roof. Everything else is site and specification. Temperature swing on a steel shell drives condensation decisions that outrank most layout preferences.
Proportion drives cost here as much as size does: 360 ft of wall around 8,000 sq ft is 0.045 ft of wall per enclosed square foot, and a squarer plan of the same area would carry less. What moves the figure further on a a shared building holding forage at one end and equipment at the other is the fit-out mixed hay and equipment storage implies, along with framed openings and the height chosen for the 80 ft span.
- eave height set by handling clearance above the stack
- how many sides remain open
- the apron the loader and trailers use
- roof drainage over an open working face
Overview
A 80x100 hay barn planned as a shared building holding forage at one end and equipment at the other
This page is ordered around height and clearance, because at 80x100 the 20-foot eave limits a hay barn sooner than the plan does.
The footprint holds 15 shared bays — 5 across by 3 deep — and leaves 16 feet of depth for a separation strip between the stacked end and the parked end that keeps chaff, dust and fuel apart.
Read this footprint through its span. 80 feet across is the fixed constraint; 100 feet of length is the negotiable one, and at 1.25 to 1 the building is close to square, so movement runs in both directions. Height is the dimension people regret; it cannot be added later without rebuilding the frame line.
A 80 by 100 footprint is a mildly directional plan: 8,000 sq ft enclosed by 360 ft of wall, at a 1.3:1 length-to-width proportion. Along its 100 ft dimension it takes 4 runs of shared bays at 24 ft, leaving 4 ft over — the 4 ft is where the argument about this size actually happens. Mixed buildings are normal on a working farm and are rarely planned as such. The two uses have genuinely opposed requirements — one wants air movement and an untouched stack, the other wants a hard floor and frequent movement — and the plan should state which one is the priority. A store that can be filled from two directions halves the queueing on the busiest day of the year.
This footprint is planned as a shared building holding forage at one end and equipment at the other. Seasonal peaks fall at different times, which is what makes the pairing work: the equipment end empties as the stack fills. The plan should be drawn against the week when both are full at once. The apron outside carries as much of the operation as the floor inside; in a wet harvest it decides whether filling continues.
Areas, perimeter, roof area, ridge height, slab volume and the shared bay counts on this page are computed from the stored 80x100 record and this platform's planning module for the hay barn category.
Height
Interior height for a 80x100 hay barn
The stored configuration carries a 20-foot eave and computes to 33.3 feet at the ridge on a 4:12 pitch — a 13.3-foot rise across 80 feet. Height is therefore not uniform, and the sidewall is the constraint. A building that cannot be reversed out of is a building that gets used in one direction only.
Height on a 80 ft span is a separate decision from the 100 ft length, and it is the span that sets the frame's behavior. Raising the eave over 8,000 sq ft affects every bay along the 100 ft dimension, so the test is whether mixed hay and equipment storage genuinely needs the extra clear height or only the floor area.
Ventilation across 8,000 square feet at this height: airflow through a stack is the reason many hay barns stay open-sided; enclosing them changes how the stored crop behaves.
Clear height below purlins, bracing and lighting is lower than the eave height. The usable figure comes from the manufacturer's framing for the selected building.
Usable area
How the 8,000 square feet divides at 80x100
Computed shared bay fit for a 80x100 hay barn
| Measure | Computed at this footprint |
|---|---|
| Shared bays across the 80-foot width | 5 at a 14-foot module |
| Leftover width | 10 ft (1,000 sq ft as a full-length strip) |
| Rows along the 100-foot length | 3 at a 24-foot module after 12 ft of circulation |
| Leftover depth | 16 ft (1,280 sq ft across the width) |
| Total shared bays | 15 |
| Share of floor committed | 63% |
Module footprint used here is 14 by 24 feet, this platform's planning module for a hay barn. It is not a code minimum or an engineered clearance.
Example allocation of the 100-foot length — planning model, not survey data
| Zone | Length along the building | Computed area |
|---|---|---|
| Equipment bays | 60 ft | 4,800 sq ft |
| Material and input storage | 25 ft | 2,000 sq ft |
| Working and turning space | 15 ft | 1,200 sq ft |
Shares applied to the stored 100-foot length; areas computed against the 80-foot width.
Module footprints and allocation shares come from this platform's use typology and are published as example planning models. They are not recommendations and do not describe a majority of projects.
Allocation
Dividing the floor for a shared building holding forage at one end and equipment at the other
The storage arrangement this floor tends toward in a heavy season is a wide-face store where most of the stack is reachable from the outside: the face has no covered strip, so anything staged in front of the stack is exposed and has to be moved the same day. Dividing the 8,000 sq ft by the 14 by 24 ft shared bay gives roughly 16 positions before circulation is deducted a second time for cross movement. Whether the plan keeps 16 or drops to 12 comes back to the question this footprint is really answering: what does storing forage next to machinery cost each of them?
Depth arithmetic leaves a working end zone here. 1,280 square feet sits past the last row, which is why 80x100 tends to be planned with a separation strip between the stacked end and the parked end that keeps chaff, dust and fuel apart designed in rather than added later. A wider bay is a structural decision and a longer bay is a layout decision; the two are often confused.
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. Service routes are cheap to plan now and expensive to retrofit through a finished shell.
Seasonal peaks fall at different times, which is what makes the pairing work: the equipment end empties as the stack fills. The plan should be drawn against the week when both are full at once. The apron outside carries as much of the operation as the floor inside; in a wet harvest it decides whether filling continues. That movement pattern, not the 8,000-square-foot total, is what decides whether the leftover 16 feet is useful here.
Openings
Openings for 5 shared bays across
One opening per position works on this gable: 5 across 80 feet, with 10 feet of wall to distribute as piers. Splitting that margin evenly is what keeps the elevation buildable. Noise from this floor reaches the office, the neighbours and the yard, and separation is a plan decision.
The equipment end needs a wide door; the stacked end needs air and a working opening. Treating both as the same kind of opening is what makes mixed buildings underperform at both jobs.
Loader-handled from the open side, with the working face moving as the stack grows and shrinks.
Framed-opening sizes, headers and the structure around them are engineered for the specific building. Confirm every opening with the door supplier and the building manufacturer before ordering.
Configurations
Configuring 15 shared bays at 80x100
At 25-foot nominal bays the structure works with the layout instead of against it: one shared bay per bay line, walls free of awkward half-positions. Every foot of width added multiplies through the roof and the frame; every foot of length mostly adds skin.
Depth here creates a hierarchy: 3 rows means front positions get used and rear positions get filled. Deciding which is which up front is what keeps 80x100 workable. Cleaning, maintenance and inspection all need reach, and reach is planned in the gaps rather than in the modules.
Mixed buildings almost always grow at the equipment end, because equipment is what accumulates. Reserving that end for extension keeps the stack undisturbed.
Configured as a shared building holding forage at one end and equipment at the other, 80x100 is judged on whether the 15 shared bays 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 racking or work zones on both sides with a full vehicle lane down the middle, or does it need a second lane that this 80-foot span cannot give?
- Is the 100-foot length being bought for depth, or for the repeated bays — eight to ten repeated bays, which makes the layout a scheduling problem as much as a spatial one?
- What stack height do you plan, and can the loader place a bale above it inside the building?
- Which sides stay open for airflow, and which face the weather?
Bay division shown here is a planning module computed from the stored length. Actual bay spacing is set by the manufacturer's frame design for the building.
Comparison
What changes at adjacent footprints
Computed comparison of nearby footprints for a hay barn
| Footprint | Floor area | Shared bays |
|---|---|---|
| 40x80 | 3,200 sq ft | 8 (2 x 4) |
| 60x60 | 3,600 sq ft | 12 (4 x 3) |
| 50x80 | 4,000 sq ft | 6 (3 x 2) |
| 40x100 | 4,000 sq ft | 12 (3 x 4) |
| 60x80 | 4,800 sq ft | 8 (4 x 2) |
Areas computed from each stored size record; shared bay counts computed with the same 14 by 24 foot planning module.
- 40x80 moves the count from 15 to 8 shared bays (2 across by 4 deep), which is the reason to choose between them.
- 60x60 moves the count from 15 to 12 shared bays (4 across by 3 deep), which is the reason to choose between them.
- 50x80 moves the count from 15 to 6 shared bays (3 across by 2 deep), which is the reason to choose between them.
Nearby footprints read for a hay barn: exact change in area and in planning shared bays
| Footprint | Area Δ | % Δ | Shared bays at that footprint | What changes for this use |
|---|---|---|---|---|
| 50x150 | −500 sq ft | −6.2% | 10 (2 x 5) | −5 shared bays on the same planning module. |
| 60x150 | +1,000 sq ft | +12.5% | 15 (3 x 5) | Same shared bay count on this planning module; the difference is circulation and stored depth, not capacity. |
| 80x120 | +1,600 sq ft | +20% | 16 (4 x 4) | +1 shared bay on the same planning module. |
| 80x80 | −1,600 sq ft | −20% | 15 (5 x 3) | Same shared bay count on this planning module; the difference is circulation and stored depth, not capacity. |
Areas are arithmetic on two stored size records; shared bay counts use this platform's 14 by 24 foot planning module and are not a capacity statement.
Because this footprint is planned as a shared building holding forage at one end and equipment at the other, the useful next reads are different from the ones a differently shaped hay barn suggests: mixed hay and equipment storage, use separation planning, seasonal peak planning.
Visualization
Reading the 80x100 footprint as a hay barn
FAQ
Questions about 80x100 hay barn projects
About 1,280 square feet across the width — enough for a separation strip between the stacked end and the parked end that keeps chaff, dust and fuel apart.
Reserving 12 ft across the 80 ft dimension for movement leaves 68 ft of working width, which takes 4 shared bays at 14 ft. Along 100 ft it takes 4 runs at 24 ft. That is 16 positions out of 8,000 sq ft, and the remainder is circulation, walls and the margin every plan needs. Whether that count is enough depends on what does storing forage next to machinery cost each of them. These are planning figures computed from the footprint, not a quoted layout.
It depends on the loader lifting a bale to the top of the intended stack, which is higher than the stack itself. The stored configuration computes to 33.3 feet at the ridge, but the eave is the number that governs anything standing near a wall.
The equipment end, because it is entered daily. A stack is filled in a burst and drawn down through a smaller opening.
The footprint holds 15 shared bays — 5 across by 3 deep — and leaves 16 feet of depth for a separation strip between the stacked end and the parked end that keeps chaff, dust and fuel apart. Those counts use a 14 by 24 foot planning module with 12 feet allowed for circulation, so a different module changes the answer.
Methodology
How this page was produced
Sources and methodology
Find Steel Buildings dimensional records
Find Steel Buildings · Primary platform dataset · Tier 1 — code authority, standards body, primary dataset or manufacturer engineering
Supports: Stored nominal width, length, eave height, roof pitch and slab thickness for this subject.
International Building Code and International Residential Code
International Code Council · Model code · Tier 1 — code authority, standards body, primary dataset or manufacturer engineering
Supports: The framework of adopted codes and local amendments that decides permitting, separation and opening requirements. Cited as the governing framework, never as a local requirement.
- Dimensional figures: Width, length, eave height, roof pitch and nominal slab thickness come from this platform's stored record for the subject. Floor area, perimeter, wall area, roof area, ridge height and slab volume are computed from those inputs rather than transcribed.
- Shared bay fit: Counts, leftover strips and per-module areas are computed from the stored 80x100 record against this platform's 14 by 24 foot planning module for the hay barn category, with 12 feet allowed for circulation. The module is editorial planning typology, not a code minimum or an engineered clearance.
- Allocation model: Zone shares come from this platform's use typology for agricultural equipment and crop shelter and are applied arithmetically to the stored 100-foot length.
- Allocation and layout models: Layout splits are arithmetic on the stored footprint, published as example allocation models. They are not survey findings and do not describe what buyers most often choose.
- Clearance and opening guidance: Clearance and opening statements are planning guidance. Final dimensions depend on the selected door system, header detail and the manufacturer's engineering for the building.
Methodology notes
- Prices: No price figure appears on this page. Cost data is published on this platform only with a documented inclusion basis, a collection date and a named source.
Drawn to scale
Plans and dimensions
Every drawing below is generated from the exact dimensions for this building, so proportions and areas are accurate.
Continue your research
Related planning topics
Background reading on the questions this page raises. None of these pages sells anything.
Compare 80x100 hay barn configurations
Review the allocation models for this footprint side by side, then estimate the configuration you intend to build.