Crack Monitor Installation INSTRUCTIONS | CRACKMON® 4020A


Thank you for purchasing Buildera™ CRACKMON® structural crack monitors, the engineer’s choice™. Buildera designs and manufactures the CRACKMON 4020A in the USA, providing years of reliable indoor and outdoor endurance. Follow this installation guide and all safety precautions to ensure a fail-proof installation. Always wear eye protection and gloves when using power tools and structural adhesives.


Anchor & Fastener (Method 1)

  1. Clean and remove loose debris from crack using stiff bristle or wire brush.
  2. Adhere CRACKMON 4020-TMP drilling template over crack or use CRACKMON 4020A-DT installation Drill Tool (EAN 0816291010372).
  3. Bore four 1-1/2” (3.8cm) deep holes using a cordless hammer drill and 3/16” (ø5 mm) concrete bit. Blow out debris from hole. Use eye protection!
  4. Insert one 3/16” (ø5 mm) A5 Toggler® Alligator® anchor into each hole. Tap flush with a hammer. For best results, do not use any other anchor.
  5. Fasten CRACKMON with four #6 or #8 x 1-1/2” stainless-steel pan-head SMS and washers, or use optional mounting plate in lieu of washers. Over-torquing screws may inadvertently damage the gauge or shear off the screw head.
  6. Tighten last turns by hand. Cut/score clear tape with a sharp knife or razor blade. Remove residual tape from CRACKMON to allow free motion.
  7. Note X-Y start position on TRACARD® or progress sheet. Inspect movement periodically. Document with phone/camera and CRACKMON 224R Crack-Width Comparator (ACI compliant).
  8. Mount with tamper-resistant screws and epoxy for best results and security.

Structural Epoxy (Method 2)

  1. If surface is damp, use Method 1.
  2. Clean and remove loose debris from crack using stiff bristle or wire brush.
  3. Mix approved Buildera STRUPOXY™ adhesive or Aboweld 8101-5 epoxy following directions on package.
  4. Apply 1-2mm layer of epoxy to backside of both CRACKMON mounting tabs in the vicinity of holes (2cm x 3cm area). Rough or uneven mounting surfaces may require a thicker application.
  5. Press CRACKMON firmly into place across crack at 1-m (3-ft) typical unit-to-unit spacing. Epoxy fills holes.
  6. Center red crosshairs on grid and over crack. Level and adjust to ensure accurate grid alignment prior to initial setup. Hold in place for approximately five (5) minutes until initial bond sets.
  7. Secure CRACKMON in place with duct tape for 24 hrs until epoxy cures.
  8. After curing, remove duct tape. Cut/score clear tape with a sharp knife or razor blade. Remove residual tape from CRACKMON to allow free motion.
  9. Note X-Y start position on TRACARD® or progress sheet. Inspect movement periodically. Document with phone/camera and CRACKMON 224R Crack-Width Comparator (ACI compliant).