Assemble Vertical Side Frames
From Under-Stair Shelving · Step 7 of 10 · Video by The Weekend Builder

Showing 1:05–1:57 of the source video. Watch the full video with every moment.
What happens in this clip
Lay out the cut 2x4 lumber pieces on the floor to form the rectangular side frames for the shelving units. These frames will serve as the vertical supports for your shelves. Once laid out, use a cordless drill and appropriate wood screws to securely fasten the pieces together. Ensure all joints are flush and the frames are square by checking with a speed square or tape measure before fully tightening the screws. Create multiple identical frames for all the vertical supports.
Goal: Construct the rectangular side frames for the shelving units.
What's used
Tools
- 2x4 Lumber (Cut)
- Cordless Drill Ryobi
- Impact driver
- Speed Square
- Tape Measure Milwaukee
Materials
- Wood Screws GRK
- Construction screws
About the full video
This project provides detailed instructions for building sturdy, floor-to-ceiling storage shelves in a basement. It covers measuring the space, cutting lumber and OSB sheets, assembling the wooden frames, attaching the shelf surfaces, and finally installing and organizing items on the finished shelves to maximize storage space.
Step 7 of 10: Assemble the Main Frame
Begin assembling the main structural components of your shelving unit. Apply wood glue to the joints and secure them with screws. If your design includes a back panel or vertical dividers, attach them now. Ensure the frame is square and sturdy.
Every video in Under-Stair Shelving
Step 1: Measure the Under-Stair Space
- 1:09–1:46 Measure, Cut, and Test-fit
- 0:09–1:25 Initial Measurements and Platform Design
Step 2: Design the Shelving Unit
- 0:13–0:17 Install Modular Shelving Frames
- 2:57–3:12 Construct Wider Center Shelves
Step 3: Create a Cut List
- 3:46–5:30 Create Cut List and Verify Thickness
- 0:38–1:39 Prepare Lumber and Cut List
- 0:02–0:04 Cut and Prepare Lumber
Step 4: Purchase Materials
- 0:00–0:03 Gather Materials and Tools
- 0:00–0:17 Gather Materials and Tools
- 0:00–0:49 Gather Tools and Materials
Step 5: Cut the Materials
- 1:03–2:43 Cut All Lumber to Size
- 1:18–1:29 Cut Timber to Length
- 0:11–0:58 Cut and Rip Lumber
Step 6: Sand All Pieces
- 1:24–1:29 Sand All Components
- 2:06–2:19 Sand All Cut Pieces
- 0:27–0:30 Sand Wood Pieces
Step 7: Assemble the Main Frame
- 2:26–2:55 Assemble Main Shelf Box
- 1:05–1:57 Assemble Vertical Side Frames (this video)
- 0:06–0:11 Assemble the Main Frame
Step 8: Install Shelves
- 5:42–6:03 Install Reinforced Shelves
- 4:56–5:53 Install Internal Divider Shelves
- 5:19–5:45 Install Shelves
Step 9: Finish the Unit
- 0:39–0:49 Paint and Install Hardware
- 0:43–0:49 Paint All Wood Components
- 12:47–13:48 Apply Wood Finish
Step 10: Install the Shelving Unit
- 3:20–4:12 Install & Secure Bookcase in Alcove
- 3:22–6:20 Install Shelf Units and Supports
- 0:13–0:17 Install Modular Shelving Frames
Questions about Under-Stair Shelving
What are the essential tools I need for accurate measurements in an angled under-stair space?
Beyond a standard measuring tape and pencil, an angle finder or a protractor is crucial for accurately capturing the slope of the stairs. Also, a long straight edge or level will help you mark level lines and check for plumb, ensuring your shelves are straight and true despite the angled surroundings.
Beyond basic hand tools, what power tools would make this under-stair shelving project easier for a beginner?
A miter saw or circular saw with a guide will significantly improve the accuracy and speed of cutting your lumber, especially for repetitive cuts and angles. An electric orbital sander is also highly recommended to efficiently prepare all pieces for finishing, saving you hours compared to hand sanding.
What are the most important safety precautions I should take when cutting and assembling lumber for this project?
Always wear safety glasses to protect your eyes from sawdust and flying debris. Use hearing protection when operating power tools and ensure your work area is clean and well-lit to prevent accidents. Make sure all lumber is securely clamped or supported before cutting to avoid kickback.
The project is listed as 'beginner' and '3 days'. Is this estimated time realistic for someone completely new to woodworking?
While classified as beginner, the 3-day estimate often assumes some prior familiarity with tools and a focused work schedule. If you're completely new, allow for extra time, especially for careful measuring, precise cutting, and thorough finishing, as these steps are critical for a professional-looking result. Don't rush the process.
What's a common mistake beginners make when measuring for under-stair shelving, and how can I avoid it?
A frequent mistake is not fully accounting for irregularities in the wall or floor, or failing to precisely capture the stair's varying angles, leading to shelves that don't fit snugly. To avoid this, create a detailed template using cardboard or scrap material for complex angles, and always 'measure twice, cut once' to confirm dimensions.
Are there alternative materials to dimensional lumber that might be easier for a beginner or offer a different look for under-stair shelving?
Plywood or MDF (medium-density fiberboard) can be good alternatives, often providing flatter surfaces and being easier to cut into large panels for shelves and backs. These materials typically require edge banding or painting for a finished appearance, which might add a different aesthetic and complexity to the finishing steps. Consider pre-made shelving kits for the simplest approach, though customization will be limited.
Under-Stair Shelving
Design and construct open shelving or a bookcase unit to fit within the under-stair space, maximizing storage and aesthetic appeal.
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