What are the advantages of purchasing an F.J. Moore plumbing vent flange/flashing ?


Our two part plumbing vent flange/flashing encloses the entire vent pipe above the roof.  We don't use a rubber seal to prevent water leaking into the attic, which also reduces exposure to mold and mildew.  Patented in 1918, our design remains superior to all others in the marketplace. Galvanized or painted steel with a lead top is usually good for the life of the roof.

Install it once, properly, and we guarantee it for ten years. Without a rubber seal to deteriorate, most likely the F.J. Moore plumbing vent flange/flashing will last longer than the roof surface.


How does an F. J. Moore plumbing vent flange/flashing work ?



The Base of our vent flange/flashing is set to the roof's pitch and set under a row of shingles above it to provide water drainage. The top cylinder slides over the base cylinder and attaches to the top of the plumbing vent pipe. As the roof expands and contracts, the base rises and falls while the top stays stationary. The roof surface can flex with temperature without compromising the seal.


Why is a rubber seal flange inferior to the F.J. Moore design ?


A Rubber Seal dries out and becomes brittle when exposed to the sun's UV rays and temperature extremes. The roof expands and contracts, causing the rubber seal to slide up and down on the vent pipe.  As the rubber ages, movement of the roof causes the rubber to deteriorate and allow moisture to leak into the attic.  Most new homes use rubber seal flanges for cost savings more than design. Most re-roofs in Minnesota and surrounding states use the F. J. Moore frost resistant plumbing vent flange simply because it's a superior product.


Is the F. J. Moore plumbing vent flange/flashing worth the cost ?



Our flange/flashing retails for about twice the cost of a rubber seal version.  With two per roof, a tiny $20 increase, lost in the thousands involved in an overall roof replacement budget.

Factoring in the time savings with ease of installation, our written ten year guarantee, typical performance lasting another twenty, we're confident the answer is yes.

Painted vent flanges cost slightly more for materials, but they cover the glowing white plumbing pipe sticking out above the shingles. Choosing a color to complement the roof  provides a more finished look along with our superior design features.


Are F. J. Moore plumbing vent flanges/flashing difficult to install ?



Refer to our detailed printable installation instructions under How To Order. As our flanges require no removal of the old one, or shingles or sealing with roofing tar, they are not difficult to install.


How do I measure the inside dimension of the plumbing vent pipe ?



Most plumbing vent pipes are made of PVC plastic, cast iron or copper. Place a good steel ruler across the top of the plumbing vent pipe. Measure from the inside edge of one side directly across to the opposite inside edge. Note this measurement as the inside vent pipe diameter.  

All residential plumbing is a standard  2", 3", 4", 5" or 6" inside diameter. Should you require a flange for a non-standard application, please contact us directly.


How do I know if I need a standard or high pitch vent flange ?



Refer to our detailed instructions for measuring roof pitch under How To Order. Standard vent flanges are adjustable to fit 1/12  to 11/12 roofs. High pitch vent flanges adjust to fit  5/12 to 15/12 roofs. If the roof pitch is 11/12 or more, a high pitch flange is necessary.


Do you make vent flanges not shown on the catalog pages ?



We welcome custom orders.  Please contact us with your request.


Where can I buy F. J. Moore vent flanges/flashing locally ?



Please refer to our dealer page for companies that sell and install our products. Call ahead to check for items in stock. Business’s offering our vent flanges over the counter are primarily located in the five state upper midwest area (MN, WI, IA, ND, SD), while we are constantly working towards national distribution.


What is the CVV Code on a Credit Card ?



Card Verification Value (CVV) is the authentication code procedure used by credit card companies to fight fraudulent internet transactions. The cardholder enters the CVV number at the time of the order to verify the card is on hand, instead of actually presenting the card in person. The CVV code is three or four numbers used to validate the information embossed on the card, but not part of the card number itself.

The back of Visa and MasterCards contain the 16 digit account number followed by the CVV/CVC code.  Some banks only show the last four digits of the account number followed by the code. 

For your protection we require the 3 or 4 digit code on the back of your credit card.  Your online ordering information is protected by Secure Socket Layer (SSL) technology certified by a digital certificate. Please see the SSL discussion in our Privacy Notice, left hand column of our Catalog pages.