How to Wash LEGO Bricks with Water — The Safe Way
When Water Is Safe, When It Isn't, and the Exact Process to Use
Water can be a powerful cleaning tool for LEGO bricks — but only in the right circumstances. Knowing when and how to wash LEGO bricks with water safely is essential for collectors who want to deep-clean loose pieces without risking damage.
The most important rule first: never submerge or wet-clean assembled display builds. Water should only be used on loose, disassembled pieces.
When Can You Use Water on LEGO?
Safe for Water Cleaning:
- Loose, unattached LEGO bricks with no internal mechanisms
- Basic plates, tiles, and standard bricks
- Parts with no stickers or printed decorations
- Older bulk bricks being restored
Never Use Water On:
- Assembled display builds — water traps between bricks and causes spotting
- Electronic LEGO components — Powered Up, BOOST, MINDSTORMS motors, light bricks
- Stickered parts — water lifts adhesive and warps sticker edges
- Printed elements (pad-printed) — water and friction can damage printing
- Rubber bands, string, or fabric elements — may shrink, stretch, or degrade
- Chrome or metallic-finish pieces — water can cause oxidation and dulling
What You Need
- Clean sink or basin
- Cool or lukewarm water (never hot — hot water can warp ABS plastic)
- Mild dish soap — a small drop only
- Mesh Wash Bag — to contain small pieces during washing
- Clean, lint-free towel or drying rack
- Well-ventilated space for air drying
Step-by-Step: How to Wash LEGO Bricks
Step 1 — Sort and Inspect
Before washing, sort pieces and remove any that shouldn't get wet (see the list above). Check for any electronic components or parts with stickers.
Step 2 — Load the Mesh Wash Bag
Place small pieces into the Mesh Wash Bag. This prevents tiny elements from going down the drain and keeps pieces contained during agitation. Larger pieces can be washed individually.
Step 3 — Rinse First
Rinse pieces with cool water before adding soap. This loosens surface dust and debris and reduces the amount of soap you'll need.
Step 4 — Add Minimal Soap
Add a single small drop of mild dish soap to the water. LEGO doesn't need much detergent — the goal is to cut oil residue, not strip the plastic. Too much soap leaves residue that dries as a white film on surfaces.
Step 5 — Gently Agitate
Swish the bag or individual pieces in the soapy water for 30–60 seconds. Avoid vigorous scrubbing — gentle movement is all that's needed. For stubborn oil stains, a soft toothbrush (dedicated, not bathroom) can be used on individual pieces with very light pressure.
Step 6 — Thorough Rinse
Rinse thoroughly under running cool water until no soap residue remains. Soap film that dries on LEGO surfaces creates an off-white haze. Take your time with this step.
Step 7 — Proper Drying
This step is critical. Improper drying causes water spots, white mineral deposits, and trapped moisture in hollow bricks.
- Spread pieces in a single layer on a clean, lint-free towel
- Rotate pieces every few hours to release water from hollow interiors
- Allow to air dry completely — at least 12–24 hours for bulk pieces
- Never use heat (hair dryers, direct sunlight, dishwashers) — heat warps ABS plastic
- Stud-up drying position helps water drain from stud interiors
After Drying: Before Reassembly or Storage
Once completely dry, give pieces a final inspection:
- Check for any remaining white mineral deposits (wipe with barely damp Microfiber Cloth)
- Confirm all hollow interiors are fully dry before reassembly
- Store in a clean, dry container with good airflow if not reassembling immediately
What About the Dishwasher?
This method circulates online, but we do not recommend it. Dishwashers use hot water and high-pressure jets that can warp ABS plastic, fade colors, damage printed elements, and cause significant clumping and friction damage to pieces. The convenience isn't worth the risk.
For dry cleaning of assembled builds, see our Ultimate Guide to Cleaning LEGO Sets and our guide on how to remove dust from LEGO sets safely. For a full care routine, see our LEGO maintenance guide for collectors.
The Brick Buff Cleaning Kit includes the Mesh Wash Bag for safe water cleaning of loose pieces, alongside the full dry-cleaning tool set for assembled builds.
