Structural Crack Monitoring—Redefined

When Buildera designed the new CRACKMON® 4020A Building Foundation Crack Monitor, we sought a fresh approach that balanced the time-honored familiarity of classic crack monitors with modern digital manufacturing technology. The result: a vibrant new generation of flexible crack monitors for demanding commercial and industrial use. Just as important, we engineered and built the product from the ground up in the USA, underscoring our commitment to American ingenuity and jobs.

The heavy-duty CRACKMON® 4020A offers several innovations so unique that we're patenting not only the novel new features, but also the manufacturing process, installation method, and data collection.

Features and Benefits

  • Extreme durability—50% thicker proprietary polymer compared to classic model (4.5 mm vs 3 mm)
  • New 2D+ polar magnitude and X-Y displacement measurement grid with precision TickPoints™ improve measurement accuracy
  • Vibrant rich-black and red printing on opaque white background doubles the contrast and legibility
  • Unique serial IDs yield unprecedented engineering traceability in a crack monitor
  • Integrated GeoQR™ technology for online instructions, ordering, and geolocation tagging*
  • Flexible mounting arrangement optimized for #8(M4) or #6(M3.5) tamper-resistant fasteners and epoxy
  • Available tamper-resistant Torx Plus® stainless-steel screws and anchors made in USA
  • Optional impact-absorbing thermoplastic drilling guide aligns hole centers while hammer-drilling concrete
  • Co-branding and custom mobile-response options and sizes available—consult Buildera for program details

Detailed Description

2D+ Polar Magnitude and X-Y Measurements
In addition to familiar X-Y 2D Cartesian measurements, the redesigned measurement grid now includes a new polar-magnitude measurement function, effectively computing the angular hypotenuse (magnitude) of change from the zero-crossing. That's why we call it 2D+.

What's more, to improve reading accuracy over the entire range, the measurement grid now sports variable-length tick marks, as well as patent-pending TickPoints™ at 1 mm x 1 mm intervals. TickPoints™ improve measurement accuracy as the measurement cross-hairs traverse the grid. This is particularly helpful when the two plates are no longer parallel.


Vibrant, High-Contrast Measurement Grid
Unlike our prior generation of crack monitors that were pad or screen printed in one black color, we print the new CRACKMON® 4020A in five process colors, including a high-contrast rich-black text UV-cured over a thick double layer of brilliant opaque white ink. The result is a bright, bold measurement grid with a 2X contrast improvement that's much easier to read over a wide range of lighting conditions. 

Engineering Traceability to the Crack
To improve engineering traceability, each CRACKMON® 4020A crack monitor features a unique 15-character serial number that tracks the country of origin, design revision, and unique ID. This ensures engineering traceability in the field and offers a significant benefit and professionalism in forensic analysis.

Buildera GeoQR™ Mobile Installation Instructions and Tips
To put information at your fingertips, an imprinted QR code works with your mobile phone to access installation instructions and other helpful data, wherever you may be.

Peel It. Stick It. Drill It.™
Installers know that mounting a crack monitor using fasteners can be frustrating. Marking and aligning holes in one hand while holding the crack monitor in the other is a sure-fire way to lose your cool. And when it comes to hammer-drilling hard or rough surfaces like concrete or stucco, the percussive impact from a hammer-drill makes it tough to accurately drill holes in the right place. Buildera's new impact-absorbing drilling guide (patent pending) features an aggressive adhesive that sticks to concrete, masonry, stucco, steel, wood, and other rough surfaces. Simply peel it, stick it, and drill it. You'll get perfect holes every time—saving time and money on the job.

Flexible, Tamper-Resistant Mounting Options
Improved mounting options now include both horizontal and vertical slots, optimally sized to accept four different screw types including English (#8/#6) and Metric (M4/M3.5) fasteners, respectively. Optionally available is a stainless-steel Torx-Plus® tamper-resistant mounting kit and anchors. To avoid damaging the crack monitor, Buildera also supplies corrosion-resistant stainless-steel washers to help distribute the load for a secure installation.

Available Shims for Z-axis Compensation
Not all cracks are coplanar. Buildera offers handy pre-cut Z-Shims to compensate for Z-axis shifts perpendicular to the crack at the time of installation. Using a binary range of thicknesses, virtually any Z-axis offset can be corrected in increments of 1mm or less. Consult Buildera for available shim options.

The Best Value For Your Money
Value equals benefits minus price. With all these improvements and benefits, the CRACKMON® 4020A offers more value than any crack monitor on the market today. When purchased In bulk, prices are competitive with economy crack monitors sold today, but with the benefits and premium features that only the CRACKMON™ 4020A offers. With so much more value from the CRACKMON® 4020A you'll never turn back.

Available in Bulk for Distributors and High-Volume End Users
The CRACKMON® 4020A is available singly and in nominal quantities online and from our channel partners, or in bulk (starting at 50 qty/box) for distributors, resellers, and volume end-users. Order UPC 816291010198 | EAN 0816291010198 (box of 50).

Customizable with Co-Branded Options
Buildera welcomes the opportunity to customize crack monitors with your logo and website. We can even customize the QR code to direct to your website for re-ordering. Minimum order commitment is 500 pieces. Setup charges apply. Consult Buildera for special requests and other options.


Ordering Information

CRACKMON® 4020A (Individual Unit, No Epoxy)
UPC 816291010259 | EAN 0816291010259

Individual units sealed in a heavy-duty polybag. Includes installation instructions and crack progress chart. Mounting hardware or epoxy sold separately. Also available in bulk for resellers and volume end-users. Contact Buildera for volume pricing. Some products have volume discounts for Amazon Business customers. Log in using your business account.

CRACKMON® 4020A (3-Pack Kit with Epoxy)
UPC 816291010006 | EAN 0816291010006

The 3-pack kit includes three (3) CRACKMON® 4020A Heavy-Duty Concrete Crack Monitors and (1) 5-minute structural thixotropic epoxy. Includes installation instructions and crack progress chart.

CRACKMON® 4020A (18-Pack ContractorPak with Epoxy)
UPC 816291010013 | EAN 0816291010013

Ideal for contractors, structural engineering firms and volume end-users, this 18-pack kit includes three (18) CRACKMON® 4020A Heavy-Duty Concrete Crack Monitors and three (3) dual syringes of 5-minute structural thixotropic epoxy. Includes installation instructions, crack progress chart, and one (1) bonus CRACKMON® 224R Crack-Width Comparator.

CRACKMON® 4020A (50-Pack Bulk Box, No Epoxy)
UPC 816291010198 | EAN 0816291010198

This new bulk pack offers the best price-per-unit intended for high-volume end-users including contractors, engineers, surveyors, municipalities, and civil engineering companies. Includes fifty (50) CRACKMON® 4020A Heavy-Duty Concrete Crack Monitors per box with installation instructions, crack progress chart, and one (1) bonus CRACKMON® 224R Crack-Width Comparator. Enjoy substantial savings when buying in bulk.

UPC 816291010099 | EAN 0816291010099

Premium structural mounting epoxy engineered for superior crack monitor installation to concrete, masonry, stucco, drywall, steel, wood, and other materials. Non-sagging, thixotropic adhesive won't run down walls or cause a runny mess typical of lower viscosity epoxies. Sets up and bonds in five minutes to clean substrates. Full cure in 24 hours.

CRACKMON® 4020A Drilling Guide / Tamper-Resistant Fastener Kit
UPC 816291010242 | EAN 0816291010242

Includes engineered self-sticking hammer-drill template, tamper-resistant Torx-Plus® stainless-steel pentalobe fasteners, compression washers, and approved anchors. Requires Wiha or Wera Torx-Plus® IPR15 security driver bit (sold separately to qualified contractors and OEMs). Contact Buildera for pricing and fastener options.

Engineering Specifications


30 mm x 152 mm x 9 mm (1.20" x 6.00" x 0.35")

40 mm x 20 mm (scale divided as ±20 mm x ±10 mm)

±0.5 mm, typ.

Mounting Holes
(4) Per side

Proprietary polymer

Tensile Strength
11,000 psi (ASTM D-638)

Flexural Strength
117 MPa (17,000 psi), ASTM D-790

Tensile Impact Strength
20 ft-lb/in^2

Rockwell Hardness
M-95  (ASTM D-758)

Hole Dimensions
#8/M4 Fasteners: .60" x .20"
#6/M3.5 Fasterns: .20 x .16"

Recommended Fasteners
#8 Torx®-Plus Pan Head Security Sheet-metal Screw, Stainless Steel (18-8 alloy) and washers
(Note the use of washers during mounting it essential to securing the crack monitor and to distribute load across the mounting surface area. Tighten by hand. Do not over-torque).


Specific Gravity / Relative Density

Light Transmission-Total

Water Absorption
0.4% by weight (ASTM D-570)


Thermal Expansion (ASTM D696, -30C to +30C)
54 µm/(m-°C), 30 µin/(in-°F )

Maximum Recommended Continuous Service Temperature
< 85°C (185°F)

Deflection Temperature @ 264 psi (1.8 MPa)
95°C (203°F)

Melting Temperature
150°C (300°F)

Self Ignition Temperature
445°C (833°F)


Flame Spread Index
115 (ASTM E-84)

Smoke Density Rating
3.4% (ASTM D-2843)