Fenestration unit sealing systems with water funneling dust plugs and methods

A sealing system for a fenestration unit, the sealing system comprising:

• a fenestration frame comprising a side frame member connected to a sill, wherein the sill and the side frame member comprise an interior side and an exterior side, and wherein the side frame member extends along a side frame member axis extending away from the sill;
• a panel retained in the fenestration frame, the panel positioned above the sill, the panel comprising an interior face, an exterior face, a first edge, a second edge, a top edge, and a bottom edge, wherein, when the panel is in a closed configuration in the fenestration frame, the first edge faces the side frame member and the bottom edge faces the sill;
• a side frame member weatherstrip attached to the side frame member, wherein, when the panel is in a closed configuration in the fenestration frame, the first edge of the panel faces the side frame member, the bottom edge of the panel faces the sill, and the exterior face of the panel contacts the side frame member weatherstrip, wherein the side frame member weatherstrip comprises a cantilevered leg that, when the exterior face of the panel is not in contact with the side frame member weatherstrip, defines a channel aligned with the side frame member axis, the first channel located between the side frame member and the cantilevered leg, and wherein, when the panel is in the closed configuration, the exterior face of the panel displaces the cantilevered leg towards the side frame member to reduce a size of the channel;
• and
• a dust plug comprising:
• a base attached to the side frame member proximate the sill,
• a support member attached to the base, the support member located in the channel between the side frame member and the cantilevered leg proximate the sill,
• an exterior weatherstrip member attached to the base, wherein a portion of the exterior weatherstrip member is located in a panel-sill gap measured along the side frame member axis between the bottom edge of the panel and a top of the sill at a junction between the bottom edge, the exterior face, and the first edge of the panel when the panel is in the closed configuration, and
• an interior weatherstrip member attached to the base, the interior weatherstrip member located proximate an interior edge of the base such that the exterior weatherstrip member is located between the support member and the interior weatherstrip member, and wherein the interior weatherstrip member contacts the first edge of the panel when the panel is in the closed configuration;
• wherein the exterior weatherstrip member is located in the channel between the support member and the cantilevered leg when the exterior face of the panel is not in the closed configuration such that the panel is not in contact with the cantilevered leg of the side frame member weatherstrip;
• wherein the support member comprises a support member height measured along the side frame member axis, and wherein the support member height is greater than the panel-sill gap;
• wherein the dust plug comprises a drain channel aligned with the side frame member axis, the drain channel located between the support member and the interior weatherstrip member such that drain channel is located between the first edge of the panel and the side frame member when the panel is in the closed configuration;
• and wherein the base comprises an interior edge facing away from the side frame member weatherstrip and the side frame member comprises a cavity, wherein the interior edge of the base is recessed within the cavity such that the interior edge is obscured by the side frame member when viewed along an interior-exterior axis extending between the interior side and the exterior side of the side frame member.

A method of sealing an interface between a panel and a side frame member of a fenestration unit, the method comprising;

• positioning a dust plug on a side frame member of a fenestration panel, wherein the dust plug comprises:
• a base attached to the side frame member proximate a sill of the fenestration unit,
• a support member attached to the base, and
• an exterior weatherstrip member attached to the base, wherein a portion of the exterior weatherstrip member is located in a panel-sill gap measured along the side frame member axis between a bottom edge of the panel and a top of a sill of the fenestration unit at a junction between a bottom edge of the panel, an exterior face of the panel, and a first edge of the panel when the panel is in a closed configuration in which the first edge of the panel displaces the cantilevered leg of the side frame weatherstrip member towards the side frame member, and
• an interior weatherstrip member attached to the base, the interior weatherstrip member located proximate an interior edge of the base such that the exterior weatherstrip member is located between the support member and the interior weatherstrip member, and wherein the interior weatherstrip member contacts the first edge of the panel when the panel is in the closed configuration;
• wherein positioning the dust plug on the side frame member comprises locating the support member of the dust plug between the side frame member and a cantilevered leg of a side frame weatherstrip member attached to the side frame member, wherein the support member forces the cantilevered leg away from the side frame member proximate the sill when the panel is not in the closed configuration.