homestead.fyi / LEANTO-GH

Lean-To Greenhouse

An 8 x 12 ft lean-to greenhouse for a south wall: 2x4 front and end walls, a sloped rafter roof and film glazing, with a door and two vents.

Draft plan, generated from the model. Not yet build-tested.

142 x 94 inFootprint

93 sq ftFloor

66 to 106 inHeight

23°Slope

20 to 30 hrBuild time

~$473.36Materials, part estimate

Drawings All dimensions in inches

3D viewfinished

3D view, framingsiding and roof removed

Front elevation

Right elevation

Plan viewfrom above

Cut list: lumber Long-point lengths; angles noted

Qty	Stock	Length	Part	Cut
1	2x2	57	Batten 1.	laid on the rafter, film under it
1	2x2	57	Batten 2.	laid on the rafter, film under it
1	2x2	57	Batten 3.	laid on the rafter, film under it
1	2x2	57	Batten 4.	laid on the rafter, film under it
1	2x2	57	Batten 5.	laid on the rafter, film under it
1	2x2	57	Batten 6.	laid on the rafter, film under it
1	2x2	57	Batten 7.	laid on the rafter, film under it
1	2x2	50	Batten 1.	laid on the rafter, film under it
1	2x2	50	Batten 2.	laid on the rafter, film under it
1	2x2	50	Batten 3.	laid on the rafter, film under it
1	2x2	50	Batten 4.	laid on the rafter, film under it
1	2x2	50	Batten 5.	laid on the rafter, film under it
1	2x2	50	Batten 6.	laid on the rafter, film under it
1	2x2	50	Batten 7.	laid on the rafter, film under it
1	2x4	142	Front top plate	laid flat
7	2x4	108	Rafter	both ends plumb cut 23.1°
1	2x4	97 1/4	Left top plate	laid flat
1	2x4	97 1/4	Right top plate	laid flat
1	2x4	96	Left stud	top cut to the slope
1	2x4	96	Right stud	top cut to the slope
1	2x4	90 1/2	Right stud	top cut to the slope
1	2x4	88 3/8	Left stud	top cut to the slope
1	2x4	85	Right stud	top cut to the slope
1	2x4	80 3/4	Left stud	top cut to the slope
1	2x4	78 5/8	Left stud	top cut to the slope
1	2x4	78 5/8	Right stud	top cut to the slope
1	2x4	71 3/4	Right stud	top cut to the slope
1	2x4	69 1/8	Left stud	top cut to the slope
1	2x4	65	Right stud	top cut to the slope
1	2x4	63 3/4	Left stud	top cut to the slope
1	2x4	58 1/2	Left stud	top cut to the slope
1	2x4	58 1/2	Right stud	top cut to the slope
8	2x4	57	Front stud
1	2x4	36	Front vent header	laid flat
1	2x4	36	Front vent sill	laid flat
1	2x4	30	Right door header	laid flat
1	2x4	27	Left cripple	top cut to the slope
1	2x4	26	Left vent header	laid flat
1	2x4	26	Left vent sill	laid flat
1	2x4	25	Front cripple
1	2x4	21	Left cripple
1	2x4	5	Front cripple
1	2x4 PT	142	Front bottom plate	laid flat
1	2x4 PT	89 1/2	Left bottom plate	laid flat
1	2x4 PT	89 1/2	Right bottom plate	laid flat
1	2x6 GC	142	Sill front	on edge
1	2x6 GC	142	Ledger	on edge, lag-screwed into the wall studs
1	2x6 GC	92 1/2	Sill left	on edge
1	2x6 GC	92 1/2	Sill right	on edge

Lumber cutting diagram Lengths chosen for the lowest cost; 1/8 in kerf, 1/2 in end trim

2x2 x 8 ft

Batten 1.2 57

2x2 x 8 ft

Batten 2.2 57

2x2 x 8 ft

Batten 3.2 57

2x2 x 8 ft

Batten 4.2 57

2x2 x 8 ft

Batten 5.2 57

2x2 x 8 ft

Batten 6.2 57

2x2 x 8 ft

Batten 7.2 57

2x2 x 8 ft

Batten 1.1 50

2x2 x 8 ft

Batten 2.1 50

2x2 x 8 ft

Batten 3.1 50

2x2 x 8 ft

Batten 4.1 50

2x2 x 8 ft

Batten 5.1 50

2x2 x 8 ft

Batten 6.1 50

2x2 x 8 ft

Batten 7.1 50

2x4 x 12 ft

Left stud 4 78 5/8Left stud 2 63 3/4

2x4 x 12 ft

Right stud 5 85 1/8Front stud 1 57

2x4 x 12 ft

Front top plate 142

2x4 x 10 ft

Front vent header 36Left cripple 8 27Left vent header 26Front cripple 10 25Front cripple 9 5

2x4 x 10 ft

Left top plate 97 1/4Left cripple 9 21

2x4 x 10 ft

Left stud 1 58 1/2Right stud 1 58 1/2

2x4 x 10 ft

Front stud 3 57Front stud 4 57

2x4 x 10 ft

Front stud 5 57Front stud 6 57

2x4 x 10 ft

Front stud 7 57Front stud 8 57

2x4 x 10 ft

Rafter 1 108

2x4 x 10 ft

Rafter 2 108

2x4 x 10 ft

Rafter 3 108

2x4 x 10 ft

Rafter 4 108

2x4 x 10 ft

Rafter 5 108

2x4 x 10 ft

Rafter 6 108

2x4 x 10 ft

Rafter 7 108

2x4 x 10 ft

Right top plate 97 1/4

2x4 x 10 ft

Left stud 7 95 7/8

2x4 x 10 ft

Right stud 7 95 7/8

2x4 x 8 ft

Left stud 3 69 1/8Left vent sill 26

2x4 x 8 ft

Right stud 2 65 1/8Right door header 30

2x4 x 8 ft

Front stud 2 57Front vent sill 36

2x4 x 8 ft

Right stud 6 90 1/2

2x4 x 8 ft

Left stud 6 88 3/8

2x4 x 8 ft

Left stud 5 80 7/8

2x4 x 8 ft

Right stud 4 78 5/8

2x4 x 8 ft

Right stud 3 71 5/8

2x4 PT x 12 ft

Front bottom plate 142

2x4 PT x 8 ft

Left bottom plate 89 1/2

2x4 PT x 8 ft

Right bottom plate 89 1/2

2x6 GC x 12 ft

Sill front 142

2x6 GC x 12 ft

Ledger 142

2x6 GC x 8 ft

Sill left 92 1/2

2x6 GC x 8 ft

Sill right 92 1/2

Shopping list $416.36 checked / $57.00 estimated

Item	Store	Qty	Each	Line	Note
2x2x8 furring strip	Home Depot	14	$2.97	$41.58	see lumber cutting diagram
2x4x10 stud, SPF	Home Depot	16	$5.46	$87.36	see lumber cutting diagram
2x4x8 stud, SPF	Home Depot	8	$4.15	$33.20	see lumber cutting diagram
2x4x12 stud, SPF	Home Depot	3	$7.12	$21.36	see lumber cutting diagram
2x4x12 ground-contact pressure-treated	Home Depot	1	$7.18	$7.18	see lumber cutting diagram
2x4x8 ground-contact pressure-treated	Home Depot	2	$4.68	$9.36	see lumber cutting diagram
2x6x12 ground-contact pressure-treated	Home Depot	2	$14.18	$28.36	see lumber cutting diagram
2x6x8 ground-contact pressure-treated	Home Depot	2	$9.78	$19.56	see lumber cutting diagram
6 mil greenhouse film, 20 x 25 ft	Walmart Business	1	$83.99	$83.99	roof, front and ends
Exterior wood screws #9 x 2.5 in, 5 lb box	Home Depot	2	$29.97	$59.94
Poultry staples 3/4 in, 1 lb	Southern States	1	$4.49	$4.49
Galvanized 6 in strap hinge, each (5-pack $32.99)	Home Depot	2	$6.60	$13.20	door and vent
Galvanized staple safety hasp, 3-1/2 in	Home Depot	1	$6.78	$6.78	door
Carriage bolts, nuts and washers, 12 pack	Home Depot	1	$12.00	$12.00	lag screws
Ridge cap and flashing kit	Home Depot	1	$45.00	$45.00	flashing at the ledger
Total before tax				~$473.36

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

Choose a wall that faces south and gets 6 hr of winter sun, with no windows or doors in the 12 ft you will cover. Check the wall studs.
Lay the 2x6 sill on a level gravel pad: 142 in along the wall, with a short side at each end, and check square by measuring both diagonals.
Screw the 2x6 ledger to the wall studs with 1/4 in lag screws at 106 in, and seal the top edge with flashing under the siding.
Frame the front wall flat on the pad and stand it, then the two end walls with sloped tops cut to match the roof. Frame the door and two vent openings in the walls.
Cut 7 rafters with plumb cuts at 23.1° and set them on the ledger and the front plate, 24 in on center.
Staple 6 mil film over the rafters, front and ends, and screw a 2x2 batten over each rafter and each wall stud to hold it down.
Cut the door and vent flaps out of the film frames, hinge them and add a hasp. Add a screen in each vent.

Before you start

A lean-to against a south wall gets free heat from the house. Add a water barrel or two painted black to store it.
Check the wall: a greenhouse hides a wet wall from the sun. Seal the siding and flash the ledger so water cannot get in.
The roof slopes 23°, steeper than the 14° film needs to shed rain. In snow country, add a post at the front.
Film or twin-wall polycarbonate both work. This plan is priced for film; polycarbonate is about 4 times the cost.
Draft drawings generated from the model. Build one before selling this plan.