Stack straw bales in running bond so vertical joints never line up between courses, alternate bale direction at corners so each course overlaps the perpendicular wall, and make half-bales and custom sizes by cutting the strings, adding or removing flakes, compressing and retying with new twine. Frame door and window openings with timber boxes as you stack, building the bales tight against them.
Part of Straw Bale Construction
Bale preparation and stacking is the routine of cutting, retying and laying bales into a wall.
Stack Like Brickwork, With Tighter Bales Than You Think You Need
Bales are laid like bricks. In a running bond, each course is offset from the one below by half a bale, so the vertical joints never align and the wall behaves as one body. At the corners, the direction of the bales alternates, so that one course’s bale ends overlap the perpendicular wall and lock the corner. The material questions (which bales to accept) are in Bale Selection and Testing, and the fixings that hold the stack in Pinning and Strapping Methods.
What You Need
- Selected, dry, tight bales of consistent size.
- A bale needle: a large curved needle made from heavy wire or rebar, to thread twine through a bale.
- New twine, strong enough to hold a compressed bale.
- Timber box frames for openings.
- Rebar pins, stakes and ties.
- Tarps to cover stacked bales that have not yet been used.
Method: Lay, Offset, Frame, Adjust
Step 1: Lay the first course on the stem wall barrier in running bond.
Step 2: Offset each following course by half a bale, and alternate the corner direction.
Step 3: Make custom bales where a bale will not fit: cut the strings on a full bale, remove or add flakes (the natural layers within a bale) to reach the length, compress the adjusted bale and retie with new twine, using the bale needle to thread the twine.
Step 4: Install window and door frames as you stack, building the bales tight against them and anchoring the frames to adjacent bales with wooden stakes or wire ties.
Step 5: Compress and retie any loose bale that you can push your fist more than 5 cm into.
Step 6: Cover the finished courses at the end of each day.
Common Mistakes
- Aligned vertical joints.
- Gaps stuffed with loose straw instead of tight bales; fill small gaps with a custom bale piece or tightly packed straw.
- Stacking wet bales. Cover bales until used.
- Frames not anchored.
Safety
Fire and cutting tools
Loose and cut straw burns readily: no smoking, no open flames and no welding sparks near stacked or trimmed bales. Use a sharp knife or shears with care, and wear a dust mask when cutting bales, since straw dust irritates lungs.
What’s Next
- Learn next: Pinning and Strapping Methods
- Combine with: Surface Preparation and Mesh