Andersen 400 awning: which seal surrounds the sash?

Quick answer. In Andersen's documented 1978–2019 400 Series Perma-Shield casement/awning window configuration, the bulb-style weatherstrip runs on all four edges of the opening sash. A later continuous one-piece replacement is described for the separately scoped 1978-to-present range. The useful first question is which sash-edge component and vintage are you identifying? ¹²

Map the opening sash without guessing a part number

Create a four-edge inspection grid before doing any replacement work:

In the 1978–2019 bulb-service description, Andersen notes that replacement segments are based on window size and that vertical or horizontal pieces can be ordered in pairs. The four-edge concept is not a substitute for unit dimensions. ³

Decide which period-specific guide you need

Branch A — 1978–2019 with bulb weatherstrip: use the Andersen 000002456 article to confirm the four-edge layout and exact window identification. ¹ Record any rail/stile breaks without assuming they are intentional or that every seal must be serviced the same way.

Branch B — considering the continuous replacement: Andersen 000076881 describes a continuous one-piece weatherstrip for 400 Series Perma-Shield casement/awning 1978–present, replacing earlier vintages within that range. It replaces four previous rail/stile pieces with one piece. ²⁴ Before choosing that path, account for the official installation requirement to remove the sash. ⁵

Branch C — evidence points to 1966–1977: stop using the 1978-present claim. Andersen's separate 000005067 legacy article describes that older period, including a discontinued leaf style and a named later bulb approach. This is separate service evidence and not proof that the continuous part fits. ⁶

What to do with the result

Write one line: product family / confirmed date range / opening sash edge / installed construction / official replacement guide / unknowns. Photograph evidence of the actual seal channel and any distinct top-edge attachment. The goal is to avoid mistakenly treating a waterbar, the perimeter bulb, and a newer continuous format as one undifferentiated part.

Stop conditions: Don't infer a specific length, part number, or compatibility from year alone. Andersen's continuous installation calls for sash removal; if secure support, safe access or the relevant official instructions are missing, choose professional service rather than attempting an unsupported procedure. ⁵

Sources and references

All footnoted manufacturer facts were checked against the original publisher pages on 2026-10-11. A source describing a product family does not prove a specific unit or replacement fit.