Manufacturer and supplier of roof products and accessories for the metal building industry since 1964

Conventional / Built-up

Conventional / Built-up Roof Curb

Our conventional / built-up roof curbs feature full penetration continuous welds at all seams. We fabricate the curbs with a 3″ perimeter flat flange around the base of the curb, in addition to a 1.5″ x 1.5″ treated wood nailer to accept roofing material. Curb walls are finished with 1″ rigid insulation and may be fitted with an interior white liner. Additionally, higher R-Value insulation is available. We provide scaled CAD drawings with all orders.

  • Description
  • Model Guide
  • Sizes and Weights
  • Documents


Material 18 GA, 14 GA or 16 GA aluminized steel
1″ Rigid Insulation R7.2 (higher R-Values available)
Construction Full penetration welds, thoroughly tested
Mitered corners for true square top
Curb Base Flange 3″ perimeter base flange
Custom base flange available
Curb Top Level top when specified
Skylight curbs slope with roof
1.5″x1.5″ treated wood nailer
Dimensions 12″ height typical
1.5″ top flange
3″ perimeter base flange
Finish Galvanized steel mill finish
Certifications Engineering calcs (additional costs apply)
Warranty 1 Year


Curb Liner Conceals insulation, mill or white finish, complete kit for install
Ridge Mount Installs on ridge condition, double pitched
Collar Top Square-to-round transition
Non-Insulated Cost savings when insulation not required
High R-Value
2″ thick insulation for R14 value
Damper Shelf Damper support for exhaust fan
Duct Supports Insulated blank-offs, duct supports for HVAC equipment

Curb Model Guide

Model L x W x H Side Flanges Closures/
Insulation Gauge Material Finish Options (add all that apply)
Conventional Built-up or Membrane Roof
R: Flat Flange  NA L: Level

S: Slope w/ Roof

Y: Insulated

X: Not Insulated




B: Steel

C: Stainless Steel

NA CL: Curb Liner

RM: Ridge Mount

CT: Collar Top




Flat Side Flanges (R): flat side flanges 3″ typical
Ridge Mount (RM): Inner weight-bearing curb and outer flashing curb (heavy equipment)
Curb Liner (CL): white or mill finish liner on inside of curb wall; conceals insulationFloating
Collar-Top (CT): square-to-round transition for pipe penetrations

All curbs custom-sized to meet project specifications.


Additional curb configurations available, call for details

Product Description Model Submittal Specifications Installation Warranty
Built-up / Membrane MBS-R PDF WORD PDF

Check out our Product Line Card

R&S manufactures a vast array of products to fit your project needs. We aim to supply all of your metal building roof accessory needs, not just one product. Why go to multiple vendors when R&S can supply it all?