What Size Gasket Will I Need?
Fast Replacement Glass recommends reading your stove or fireplace owner's manual if you're unsure about which type and size (diameter) gasket you'll need for your door or window glass. For the sake of explanation, let's assume the information in your owner's manual is not clear or readily available. Let Fast Replacement Glass tell you exactly how to determine which type and size gasket you'll need!
Stove Door Gaskets
A brand new rope gasket has a circumferential shape (hence its name). Once installed and as the door is tightly closed, it is designed to flatten and fill the space between the door and the application's frame for an airtight seal.
- Closely examine the old seal. If convenient, choose a section that does not look as worn as the rest of the gasket. Next, you'll need to measure the width and depth of the channel.
- Using a blunt, slender tool (such as a flat head screwdriver), carefully and gently pry that section of the old seal out of the channel. You just need to pull out enough to configure the width of the channel with a ruler or tape measure.
- Measure across the channel (in inches) and record your measurement.
- Carefully remove any cement or adhesive residue that may remain in the channel. Once it is fairly clean, you'll need to measure the depth of the channel.
- Click on the measurement template image to download a printable pdf. When printing, remember to print at "actual size". Do not resize the pdf. Print on cardstock. (You'll want to use a stiff paper weight, as you'll need to insert the template into the channel for a precise measurement.)
- Cut out the appropriate template that is the same width of the gasket channel. (For example, if your channel is 7/8 inches wide, cut out the 7/8 inch template.)
- Next, push the edge of the template that matches the shape of the channel all the way to the bottom of the groove. (For example, if your 7/8 inc channel has a "U" shaped bottom, use the rounded edge of the 7/8 inch template. If your channel has a flat bottom, use the straight edge of the 7/8 inch template.)
- Mark the template measurement that is level with the top of the gasket channel. Remove the template and record the measurement (in inches) from the rounded or flat edge to the mark to determine how deep the channel is.
- Compare the two measurements (width and depth). Always choose the largest measurement of the two so that the gasket completely fills and seals the groove.
- If you can mold your old gasket back into a circular shape, try placing a ruler across it to measure the width. This additional measurement should give you a very specific indication of what size gasket to request.
Stove manufacturers are partial to certain methods and materials for sealing the ceramic window glass in the stove door; therefore, they will vary from one model to another. Some stoves have single panes of glass, and others have double sheets. You'll need to take a look at your stove door window to determine what has been used.
- Carefully remove the stove door and carefully place it on a cushioned surface (such as old sheets, foam, or cardboard).
- Next, remove any framing materials from the glass to evaluate the seal that has been used around or on the edge of the glass itself.
- Flat Gasket - black or white (5/8 inch): designed to fit around the edge of the glass so that a seal is created on both sides of the window. We recommend using a gasket cement for a secure adhesion. Sometimes referred to as channel tape.
- Tadpole Gasket – semi-rigid foil-wrapped core w/ adhesive back (1/2 or 5/8 inch): these adhesive backed gaskets form a tight seal on one side of the window glass with its semi-rigid core. Sometimes referred to as "bulb and tail seal." The thickness of the bulb material allows rebound from compression, while the tail conforms to uneven surfaces.
- Tadpole Gasket – soft fiber core w/ peel & stick adhesive back (5/8 inch): these adhesive backed gaskets form a tight seal on one side of the window glass, while maintaining flexibility with its soft fiber core. Sometimes referred to as "bulb and tail seal." The thickness of the bulb material allows rebound from compression, while the tail conforms to uneven surfaces.
- Rope Gasket - small diameter: in some cases, the window glass is sealed with a small diameter glass rope gasket, designed for an easy fit within the channel. We have a selection of thin rope gaskets (3/16, 1/4, and 5/16 inches) to suit your stove window's specifications.
Vermont Castings Stove
In the event that you have a Vermont Castings stove, you'll need our Griddle (or Armored) gasket for the top loader portion of your appliance. This is a rope-style seal that is encased in a stainless steel mesh. The Griddle gasket only comes in one size and is compatible with all Vermont Castings stoves.
Please continue to refer to the measurement directions above for both the stove and window gaskets on your Vermont Castings heating appliance, as both the door and the glass will require a regular rope-style gasket.