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GRB400 Rooftop Support Block

Half block (no channel)

The GRB400 half rooftop block provides all the benefits of our rooftop support blocks but in a smaller size. These versatile blocks will help save you money. Simple, versatile, and strong, the GRB400 is part of the G-STRUT® 400 Series of Rooftop Support Blocks, a customizable solution to your project's rooftop support needs.

Combining G-STRUT® rooftop support blocks with our channel, seismic bracing and accessories will simplify complex mounting or hanging projects. Whether you're shopping for a new construction or retrofit project, the combination of G-STRUT® products means unlimited ways to hang, hold and complete the job with flexibility.

Reach out to our team at Gregory Strut to see how the GRB400 can safely and securely support your project’s needs.


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Product Details

Say goodbye to commercial rooftop challenges with the GRB400. This half block is smaller in size, offering more flexibility and cost savings.

This high visibility, weather resistant support block offers proven protection for your heavy systems and equipment. Compatible with nearly any roofing material, the GRB400 dampens vibrations to prevent damage and safety concerns on your rooftop.

  • Single base, no channel
  • Comes pre-assembled at factory
  • Uses standard strut fittings and clamps
  • 100% recycled rubber block
  • UV resistant materials
  • Innovative design inhibits floating and shifting
  • Freeze and thaw resistant
  • LEED certifiable product
  • Vibration dampening
  • Compatible with most rooftop materials


  • Base length: 5 3/16”
  • Base width: 5 7/8”
  • Height: 4”
  • Materials: 100% recycled rubber base
  • Safety: Green reflector for high visibility and safety
  • Weight: 2.5 lbs
  • Static load capacity: 250 lbs
  • Ordering: 567 per skid

Proven Certifications & Associations

Group Affiliations

Evergreen Marketing Group Logo
AD Plumbing Logo
AD Electrical
NetPlus Alliance

Have a question?
Contact our Vice President of Gregory Strut, Bob Porter, to discuss your questions, goals and project requirements.

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