Door Astragals Explained: Overlapping, Split, T, Z and Meeting Stile Astragals for Pairs of Doors

An astragal seals or covers the gap where the two doors of a pair meet. This page shows how Pemko, National Guard Products (NGP) and Reese name the types - overlapping, T, split or meeting stile, adjustable, mortised and Z astragals - where they mount, and how to read the model numbers.

Astragal types as the catalogs name them

Sources: the Markar and Pemko Catalog (back cover marked 09/26) and Pemko's Astragals/Meeting Stiles pages; NGP's gasketing (NGP-CAT-GAS-0926-A) and edges and astragals (NGP-CAT-EDG-0726-A) catalogs from its Catalogs page; and Reese's 2024 Door Hardware Catalog on reeseusa.com. The table is a selection, not each maker's full list.

Pemko's website describes the 355, 356 and 359 as T-shaped astragals; the catalog draws the 357 2 inches wide in 11 gauge metal.

Pemko's catalog (page 16) also lists three astragal product types in the ANSI/BHMA A156.22 (2021) numbers printed next to products: 6 overlapping, 7 split or compensating, 8 adjustable.

Where astragals mount: active leaf, inactive leaf, one door or both

• Overlapping and T astragals. Pemko's pages for the 355, 357 and 375 Series each list "Applied to single active door in a pair of double doors". The 355 and 357 pages add: "Door coordinator needed when both doors are active". NGP's catalog says its steel 139SP must overlap the gap and the inactive door by at least 3/4 inch (page G52).
• Split and meeting stile astragals. One piece goes on each door. Pemko: "Order split astragals at two (2) pieces by door height per set of double doors" (page 154). Reese's catalog says the same of its meeting stile astragals on double doors: two lengths, one for each door (page 33). NGP marks its astragal sets "Provided as Two-Piece Set" or "Order as Set to Receive Two Pieces"; see our NGP model number guide.
• Adjustable astragals. In Pemko's catalog the 351 is surface applied, for square-edge or bevel-edge doors, and the 354 is fully mortised and designed for bullnose doors (page 158). Pemko's 351 Series page says it is for double active doors with a maximum gap of 3/8 inch.
• Mortised astragals. For its 136, NGP prints a mortise 7/16 inch wide by the desired depth (page G53).
• Z astragals. NGP's edges catalog names the leaf: the 570 is the square edge Z astragal, the 572 the beveled edge model for the active leaf and the 574 for the inactive leaf (page EA9).

Not every product in an astragal section is for a pair: Pemko lists its 3572 offset security bar "For use on single outswing wood or metal doors" (page 160).

Handing: Pemko's pages list the 355, 357, 375 and 351 as non-handed; NGP's catalog asks for an order form with the hand for its door edges and Z astragals (see our door handing chart). Our Ives flush bolt guide covers the bolts that secure the inactive leaf.

Fire-rated doors: what the catalogs print

Under its steel 139SP and 139SPDKB, NGP's catalog states: "Can Replace Astragal Required by the Door Manufacturer on Wood or Metal Fire-Rated Doors." Its page of smoke-rated astragal seals says the reverse about those seals (quoted in our NGP guide). Both notes refer to the astragal required by the door manufacturer, so check the door's label and the door manufacturer's requirements first. On page 5, headed "Fire Rated Weatherstrips and Thresholds", Reese's catalog prints: "To receive UL label on parts, add prefix 'F-' when ordering".

How to read astragal model numbers

Pemko's catalog asks for profile number, finish, insert and size or length (page 11); for split astragals it adds /2 for two pieces: 303AS84/2 is two lengths at 84 inches. ND after 357 means no drill; otherwise, the catalog says, astragals are drilled. More Pemko seal letters are in our Pemko automatic door bottom guide.

In NGP numbers such as 178SA and 143PA the seal letter comes before the finish. In Reese numbers such as 86AP (pile) and 86AV (vinyl) the finish letter follows the number and the insert letter comes last. These NGP and Reese numbers carry no length; our product pages add it to the name and the part number, as in NGP_178SA84.

Aluminum astragal, steel or stainless

The same letter can mean two finishes. A is mill finish aluminum at Pemko and Reese but anodized aluminum at NGP, where mill finish has no suffix. C is clear anodized at Pemko and Reese; dark bronze is D there and DKB at NGP. Stainless steel versions include Pemko 357SS and 305SSE, NGP 139SS and Reese 183SS.

Z astragal and 140S cut sheets we host

• NGP 570 square edge Z astragal cut sheet (PDF) - 1 page, marked copyright NGP 2015: 20 ga. cold rolled steel, for 1-3/4 inch thick doors, standard finish tan (T) powder coat. It lists lead lining as an option; NGP's current catalog says lead lining is not available on Z astragals.
• NGP 140S spring adjustable astragal seal set cut sheet (PDF) - 1 page, copyright 2015. It lists 140SB as gold; the current catalog lists B as black anodized (page G50).

Astragals at The Builders Supply

• Category: Gasketing, sweeps and weatherstripping, part of Weatherstripping and thresholds
• Brands: Pemko, National Guard Products, Reese
• Overlapping and T: Pemko 355CS96, Pemko 357C 96, NGP 178SA 84
• Split, meeting stile and two-piece sets: Pemko 305DN 96, Reese 807A 84, NGP 9605A (SET) 60
• Adjustable and mortised: Pemko 351CP 96, NGP 143PA 84
• More: Reese 184A (96 inch), Kawneer KW200762 standard astragal

Not sure which astragal fits your pair of doors? Our customer support team is available Monday - Friday, 8 AM - 4 PM Central Time, at 1-888-800-7789 or [email protected].