A 136 x 120 in pole frame with a sloped poly tarp roof, to keep hay on pallets dry.
Draft plan, generated from the model. Not yet build-tested.
136 x 120 inFootprint
72 to 84 inHeight
about 100 balesCapacity
8 to 12 hrBuild time
$286.58Materials
Drawings All dimensions in inches
3D viewfinished3D view, framingsiding and roof removedFront elevationRight elevationPlan viewfrom above
Cut list: lumber Long-point lengths; angles noted
Qty
Stock
Length
Part
Cut
1
2x4
136
Front beam
on edge, outside the posts
1
2x4
136
Front beam
on edge, inside the posts
1
2x4
136
Back beam
on edge, outside the posts
1
2x4
136
Back beam
on edge, inside the posts
7
2x4
128 5/8
Purlin
ends cut 5.7°; on edge across the beams
3
4x4 PT
94
Front post
buried 10 in
3
4x4 PT
94
Back post
buried 22 in
Lumber cutting diagram Lengths chosen for the lowest cost; 1/8 in kerf, 1/2 in end trim
2x4 x 12 ft
Front beam 1 136
2x4 x 12 ft
Front beam 2 136
2x4 x 12 ft
Back beam 1 136
2x4 x 12 ft
Back beam 2 136
2x4 x 12 ft
Purlin 1 128 5/8
2x4 x 12 ft
Purlin 2 128 5/8
2x4 x 12 ft
Purlin 3 128 5/8
2x4 x 12 ft
Purlin 4 128 5/8
2x4 x 12 ft
Purlin 5 128 5/8
2x4 x 12 ft
Purlin 6 128 5/8
2x4 x 12 ft
Purlin 7 128 5/8
4x4 PT x 8 ft
Front post 1 94
4x4 PT x 8 ft
Back post 1 94
4x4 PT x 8 ft
Front post 2 94
4x4 PT x 8 ft
Back post 2 94
4x4 PT x 8 ft
Front post 3 94
4x4 PT x 8 ft
Back post 3 94
Shopping list $286.58 checked / $0.00 estimated
Item
Store
Qty
Each
Line
Note
2x4x12 stud, SPF
Home Depot
11
$7.12
$78.32
see lumber cutting diagram
4x4x8 ground-contact pressure-treated
Home Depot
6
$11.28
$67.68
see lumber cutting diagram
Poly tarp 20 x 30 ft, 10 mil (Tarpex)
Tractor Supply
1
$62.99
$62.99
Exterior wood screws #9 x 2.5 in, 5 lb box
Home Depot
2
$29.97
$59.94
UV zip ties 11 in, 100 ct (also used for tie wire)
Home Depot
1
$17.65
$17.65
Total before tax
$286.58
Filled dot: price read from a store listing on Oct 20, 2026. Hollow dot: estimate. Prices come from the master price list, so they change when it changes.
Build steps
Mark the six post positions and check square. Dig the front holes 10 in and the back holes 22 in deep, so the tops are 84 and 72 in above the ground.
Set the posts plumb in gravel, tamped. Screw two 2x4s on edge to the outside and inside of each row of posts for a beam.
Cut the purlins with a 5.7° plumb cut at both ends and screw them across the beams every 24 in.
Lay the tarp over the purlins and wrap the edges round the beams. Screw it down through a 1x2 batten, every 12 in, so the wind does not lift it.
Lay a floor of pallets and stack the hay on top, up to 6 ft.
Before you start
It holds about 100 small square bales on pallets, or 50 on a pallet floor with an aisle. The slope drains water to the back.
A tarp lasts three to five years in the sun. Replace it when it chalks.
Keep the back toward the prevailing wind, and leave the sides open for air so the hay does not mold.
Draft drawings generated from the model. Build one before selling this plan.