Attached Greenhouse Plans

This step by step diy project is about 8×12 attached greenhouse plans. I have designed this lean to greenhouse so you can attach it to an already existing building. The greenhouse has a sturdy wooden floor and vents that are placed to the roof of the structure. Take a look over the rest of my woodworking plans, if you want to get more building inspiration.

When buying the lumber, you should select the planks with great care, making sure they are straight and without any visible flaws (cracks, knots, twists, decay). Investing in cedar or other weather resistant lumber is a good idea, as it will pay off on the long run. Use a spirit level to plumb and align the components, before inserting the galvanized screws, otherwise the project won’t have a symmetrical look. If you have all the materials and tools required for the project, you could get the job done in about a day. See all my Premium Plans HERE.

Projects made from these plans

Attached Greenhouse Plans

Building-an-attached-greenhouse

Cut & Shopping Lists

• A – 3 pieces of 4×4 lumber – 144″ long SKIDS
• B – 2 pieces of 2×6 lumber – 144″ long, 10 pieces – 93″ long FLOOR FRAME
• C – 3 pieces of 3/4″ plywood – 48″x96″ long FLOOR
• D – 2 pieces of 2×4 lumber – 144″ long, 7 pieces – 72″ long SIDE WALL
• E – 3 pieces of 2×4 lumber – 144″ long, 11 pieces – 72″ long SIDE WALL
• F – 2 pieces of 2×4 lumber – 54″ long, 4 pieces – 72″ long, 1 piece – 98″ long, 1 piece – 89 1/2″ long, 1 piece – 32″ long FRONT WALL
• G – 2 pieces of 2×4 lumber – 89″ long, 5 pieces – 72″ long, 1 piece – 5 1/2″ long, 1 piece – 11 3/4″ long, 1 piece – 18″ long BACK WALL

• 3 pieces of 4×4 lumber – 12′
• 2 pieces of 2×6 lumber – 12′
• 10 pieces of 2×6 lumber – 8′
• 3 pieces of 3/4″ plywood – 4’x8′
• 12 pieces of 2×4 lumber – 8′
• 6 pieces of 2×4 lumber – 12′
• 20 pieces of 2×4 lumber – 6′
• 2 1/2″ screws, 3 1/2″ screws, 1 5/8″ screws
• 4d nails, 16d nails
• wood filler , wood glue, stain/paint

Tools

 Hammer, Tape measure, Framing square, Level

 Miter saw, Drill machinery, Screwdriver, Sander

 Safety Gloves, Safety Glasses

Time

 One day

Related

• PART 1: 8×12 Attached Greenhouse Plans 
• PART 2: 8×12 Greenhouse Trims & Vents Plans

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How to build a lean to attached greenhouse

Building-the-floor-frame

The first step of the project is to build the floor frame for the greenhouse. Drill pilot holes through the rim joists and insert 3 1/2″ screws into the perpendicular components. Place the joists every 16″ on center and make sure the corners are square.

Fitting the skids

Fit the 4×4 skids to the floor frame. Place the skids equally spaced under the frame, after leveling the surface with attention. Use rafter ties to secure the skids to the floor frame.

Fitting the floor sheets

Attach the 3/4″ plywood sheets to the floor of the greenhouse. Align the edges with attention, leaving no gaps between them. Drill pilot holes and insert 1 5/8″ screws, every 8″ along the frame.

Side-wall-frame

Frame the small wall from 2×4 lumber. Cut the components from 2×4 lumber. Take accurate measurements and then make the cuts. Lay the components on a level surface. Drill pilot holes through the plates and insert 3 1/2″ screws into the studs. Place the studs every 24″ on center, for a professional result. Align the edges flush and make sure the corners are square.

Attached-wall-frame

Next, you need to frame the opposite side wall, the one that goes along the wall. Cut the components from 2×4 lumber at the right dimensions. Drill pilot holes through the plates and insert 3 1/2″ screws into the studs. Place the studs every 24″ on center.

Fitting the walls

Fit the wall frames to the floor of the greenhouse. Level the edges flush, drill pilot holes and insert 3 1/2″ screws through the bottom plates into the floor. Use a spirit level to plumb the wall frames.

Attached walls – OSB

Fit 1/2″ plywood or OSB to the frame that goes along the building. Inset the panels 1 1/2″ from the top plate and insert 1 5/8″ screws, every 8″ along the framing. Leave no gaps between the sheets for a professional result.

Building-the-rafters

Continue the project by making the rafters from 2×4 lumber. Use a miter saw to make cuts to both ends, as shown in the diagram. Afterwards, make another cut to the bottom of the rafter.

Rafter cut

Use a saw to make the cuts to the top of the rafter. The birdsmouth cut will help you fit the rafters to the tall side wall in a professional manner.

Fitting the rafters

Fit the rafters to the top of the greenhouse. Use the diagram so you can lay the rafters in a professional manner. Use rafter ties and screws to secure the rafters to the top plates, every 24″ on center.

Front wall – Frame

Frame the front wall from 2×4 lumber. Cut the components at the right dimensions and then assemble the frame with 3 1/2″ screws. Drill pilot holes before inserting the screws, to prevent the wood from splitting.

Back wall – Frame

Build the back wall from 2×4 lumber. Use the instructions from the diagram to frame the wall in a professional manner.

Fitting the front and back walls

Fit the front and back wall frames to the lean to greenhouse. Align the edges with attention, drill pilot holes and insert 2 1/2″ screws to lock them into place tightly.

Attached lean to greenhouse plans

You need to take a look over the rest of the project, so you see how to fit the cleats, the translucent panels and the vents. Moreover, you still need to frame the front and the back walls to the greenhouse. Therefore, take a look over PART 2 to see the next instructions.

Attached greenhouse plans

This lean to greenhouse is ideal if you want to build a shelter for your flowers during the cold days. You can easily attach this greenhouse to an existing building.

If you want to get PREMIUM PLANS for this project, in a PDF format, please press GET PDF PLANS button bellow. Thank you for the support.

This woodworking project was about 8×12 attached greenhouse plans free. If you want to see more outdoor plans, check out the rest of our step by step projects and follow the instructions to obtain a professional result.

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