DW4AFLASH – FLASHING (4″, 1/12 to 7/12)

Roof flashing seals the gap where your vent pipe passes through the roof, preventing water intrusion. This adjustable flashing fits low to moderate roof pitches (1/12 to 7/12). If you have a steeper roof, you need the high-pitch version (DW4HPFLASH) instead.

Specs: 4-inch diameter, adjustable for 1/12 to 7/12 roof pitch, galvanized steel

Replaces: 200408, 200408-EC, DW4AFLASH

Fits: 4-inch Type B double-wall gas vent on roofs with 1/12 to 7/12 pitch

In stock at Open To Public HVAC Parts in Dallas. We test parts at the counter before you buy. Call or text (214) 340-9421.

Specs

• TypeRoof flashing
• Diameter4"
• Roof pitch1/12 to 7/12
• WallDouble wall
• SizingMatch the appliance draft hood outlet - never reduce it

Cross-reference numbers

This part replaces the following OEM and aftermarket numbers:

• 200408
• DEWALTEQUIVALENT
• DEWALTOREQUIVALENTROOFFLASHING
• DW4AFLASH

Not sure if your number matches? Call (214) 340-9421 or bring the old part in — bench-testing is free.

What size flue pipe do I need?

Match the diameter of the furnace or water heater draft hood outlet. Do not reduce it. Undersizing a flue is a combustion-safety problem, not a fit problem.

What is B-vent and why is it double wall?

Type B vent has an inner and an outer wall with an air gap between them. The gap keeps the outer surface cool enough for the required clearance to combustibles and keeps the flue gases hot enough to keep drafting instead of condensing inside the pipe.

Can I use single wall pipe instead?

Only where code and the appliance instructions allow it, and single wall needs much larger clearances to anything combustible. Inside a closet, an attic, or through a floor or ceiling, B-vent is what is called for.

Solid or flexible?

Solid sections are used for straight runs. Flexible connector is for getting from the appliance to the vent where the geometry will not let a rigid section line up. Keep flexible runs as short and straight as you can - every bend costs draft.

What is an increaser?

A transition that steps the vent up from one diameter to a larger one, for example 5 inch to 6 inch, usually where two appliances common-vent together or where the vent has to match a larger existing stack.

Should I do this myself?

Flue and combustion venting is the one area where we would rather you did not guess. We will sell you the pipe and help you work out the sizing, but if you are unsure about clearances, common venting or draft, get it looked at.