How to Use HandiShims
for Perfect Window Installation
Ensure your windows are plumb, level, and square for a perfect, weather-tight fit with HandiShims. Unlike traditional wood shims that can splinter, absorb moisture, compress, or rot over time, HandiShims provide a superior, long-lasting solution.
Made from high-density plastic, HandiShims create a solid, non-compressive, and rot-proof support system around the entire window frame. This prevents the frame from bowing or twisting under pressure and protects your installation from future water damage.
Use HandiShims for:
Use HandiShims for:
- Plumbing and Leveling: Precisely adjust the window frame to be perfectly plumb (vertical) and the sill to be perfectly level.
- Squaring the Frame: Ensure the window frame is square in the rough opening, which is critical for the window sashes to operate smoothly.
- Solid, No-Squeeze Support: When you drive fasteners, HandiShims provide a flat, solid backing that resists compression, ensuring the frame stays straight and true.
- Rot-Proof Barrier: Use HandiShims at the sill to create a rot-proof gap, protecting the window and rough opening from potential moisture.
How to Use:
- Set the Window: Place the window unit into the rough opening. Start by placing shims under the sill, one at each corner and one in the center (for larger windows), to level the unit.
- Plumb the Frame: Move to the jambs (sides). Insert HandiShims in pairs (one from inside, one from outside) at the top, bottom, and middle of each side.
- Adjust for Plumb & Square: Use a level on the side jambs to check for plumb. Tap the shim pairs in or out, or swap for different thicknesses (Green 1/32”, Red 1/16”, White 1/8”, Blue 1/4”) to get a precise fit. Use a framing square or measure diagonally to ensure the unit is square.
- Secure the Frame: Once the window is perfectly positioned, drive your fasteners (screws or nails) through the window's nailing fin or jamb, through the HandiShim's "screw holes," and into the stud. The solid shim prevents the fastener from pulling the jamb out of line.
- Trim & Finish: After the window is fully secured, simply snap off the excess part of the shims. They are "scored for effortless splitting". The remaining shim stays in place permanently to provide support.