Pemko 324 Series Aluminum Sill...
IN STOCK (leaves warehouse same day if ordered before 3pm ET)
$44.13
$36.00
Pemko 324 Series Aluminum Sill Nosing cross-section diagram showing 3-1/2" (88.9mm) width dimension

Pemko 324 Series Aluminum Sill Nosing 3-1/2" Wide Threshold Cover

(No reviews yet) Write a Review

Model: 324D 36
Selected Finish is

In Stock (leaves warehouse same day if ordered before 3pm ET)

$44.13
$36.00
Adding to cart… The item has been added
Free Shipping on orders over $199
We price match and offer bulk discounts! Click Add to Quote. It's quick and easy.
✨
Earn points with this purchase! You can redeem points for giftcards, iPads, XBox's and more. View Rewards
Free Keying on all locks
You may also like

Pemko 324 Series Aluminum Sill Nosing — 3-1/2" Wide Threshold Cover

The Pemko 324 Series Sill Nosing is a UL 4L10 listed threshold cover designed to finish and protect concrete or wood sub-sills in residential and light commercial door openings. At 3-1/2" wide, it covers standard sub-sill widths cleanly, and its low-profile design keeps the threshold assembly tight without interfering with door swing. Available in aluminum alloy (Mill Finish or Dark Bronze Anodized) and extruded bronze/brass, with cut-to-length stock from 24" to 185" to fit single doors, pairs, and oversized openings.

Key Features

  • UL 4L10 Listed — meets fire-rated door assembly requirements for residential and commercial applications
  • 3-1/2" width — covers standard concrete and wood sub-sills in pre-hung door openings
  • 24" to 185" length range — accommodates single doors, pairs, and custom-width openings; field-cuttable
  • Three finish options — Mill Finish Aluminum (324A), Dark Bronze Anodized Aluminum (324D), Mill Finish Extruded Bronze/Brass (324B)
  • No exposed fasteners — secured with mastic and threshold pressure for a clean finished appearance
  • Lightweight — 0.38 lbs; low-profile height keeps the threshold assembly flush

Technical Specifications

  • Width: 3-1/2"
  • Length Range: 24" minimum – 185" maximum
  • Weight: 0.38 lbs
  • Material: Aluminum alloy (324A, 324D) or extruded bronze/brass (324B)
  • UL Listing: 4L10
  • Installation: Mastic and threshold pressure; no visible fasteners

Typical Applications

  • Residential pre-hung door installations — new construction and retrofit
  • Multi-family and apartment building door openings
  • Light commercial entrances requiring UL-listed threshold components
  • Renovation projects covering damaged or uneven sub-sills

Product Specs

Subcategory:
Thresholds
Product Group:
Door Trim and Accessories
Product Subgroup:
Door Thresholds
Product Type:
Residential Thresholds and Sills for Pre-Hung Openings
Product Model:
324
Product Dimension:
W: 3-1/2"
Product Category:
Door Trim and Accessories
Department:
Door Hardware

Pemko 324D 36 – Frequently Asked Questions

1) What is a Pemko 324 sill nosing actually for, and do I still need a threshold with it?
The 324 is a cover, not a threshold. It caps and protects a concrete or wood sub-sill in a door opening so the exposed edge is finished off. It sits under the threshold assembly and is held by mastic plus the pressure of the threshold on top of it, so it works alongside a threshold rather than replacing one. If you need the piece the door actually closes against, you want a threshold; if you need the sub-sill edge covered cleanly, this is the part.
2) Will the Pemko 324 cover my sub-sill? How wide is it?
Width is 3-1/2 inches, which covers a standard concrete or wood sub-sill in a pre-hung opening. Measure the exposed face of your sub-sill first: the 324 is an extrusion at a fixed 3-1/2 inch width, so a sub-sill wider than that will leave an uncovered strip.
3) What lengths does the Pemko 324 sill nosing come in, and can I cut it down on site?
Stock runs from 24 inches up to 185 inches, and it is field cuttable, so a long piece can be trimmed to a single door, a pair, or an odd sized opening. Ordered pieces come in 36 inch and 72 inch lengths in each finish. The 72 inch piece is the usual pick for a pair of doors or a wide entry; 36 inches covers a standard single door with trim to spare.
4) Is the Pemko 324 sill nosing UL listed for a fire rated door assembly?
UL 4L10 listed. That is the listing to cite when a threshold component is going into a fire rated opening in a residential or commercial building.
5) Aluminum or bronze sill nosing, which should I pick for an entry?
Go by what the rest of the opening is. Mill Finish Aluminum (324A) is the plain, lowest-visibility option and disappears against aluminum thresholds. Dark Bronze Anodized Aluminum (324D) gives you the dark look at aluminum weight. Mill Finish Extruded Bronze/Brass (324B) is actual bronze/brass extrusion, the one to specify when the threshold and entry hardware are bronze and you want the materials to match rather than approximate. All three are the same 3-1/2 inch width and the same mastic-set install.
6) Will screw heads show after the Pemko 324 sill nosing is installed?
No fasteners are visible. The 324 is set in mastic and held down by the pressure of the threshold above it, so the finished face is clean with no screw heads across it. Plan on mastic being on the truck; there is no anchor pack to install.
7) Will a sill nosing raise my threshold height or interfere with the door swing?
The 324 is a low profile extrusion, and that is the point of it: it adds very little height so the threshold assembly stays tight and the door swing clears. On an ADA-sensitive opening, stack it against your threshold height allowance rather than the nosing alone.
8) Can I use the Pemko 324 to cover a damaged or uneven sub-sill on a renovation instead of pouring a new one?
That is one of its normal uses. Covering damaged or uneven sub-sills in renovation work is a listed application, along with retrofit pre-hung installs. It hides the existing sub-sill face behind a 3-1/2 inch wide finished extrusion set in mastic, so you get a clean edge without breaking out concrete.
9) I manage an apartment building and want the same sill nosing on every entry door. Can I standardize on the Pemko 324?
It suits fleet standardization. Multi-family and apartment door openings are a listed application, one finish (say Dark Bronze Anodized) covers every entry for a consistent look, and the 24 to 185 inch cut-to-length range absorbs the odd wider opening without switching to a different part. The UL 4L10 listing means the same part carries through openings that need a listed threshold component.
How fast can I get the Pemko 324D 36 delivered?
Most orders ship the same day from our distribution partners, with quick delivery throughout the continental U.S. Need it urgently? Contact Us for expedited shipping options.
Can I return it if it doesn’t work for me?
Yes—ZenSupply offers a hassle-free return policy. If the product isn’t the right fit, reach out to our support team for a return authorization or setup a return by following our return instructions.
Does the Pemko 324D 36 come with a warranty?
Absolutely. The Pemko 324D 36 is backed by a manufacturer’s warranty. For full warranty terms, check the product documentation or Contact Us.
How do I get technical support or installation help for the Pemko 324D 36?
You can call, text, or email our expert support team for fast answers. We’re here to help with product selection, installation tips, and troubleshooting. Contact Us
Why buy the Pemko 324D 36 from ZenSupply?
ZenSupply makes it easy to get the commercial door hardware you need—fast shipping, expert support, and rewards on every order. Our team is always ready to help you choose the right product for your project.
!