When it comes to toilet flange sizes and types, there are a lot of things to consider. What type of flange do you need? What size should it be? How do you install it? In this comprehensive guide, we will answer all of your questions and help you choose the right flange for your needs!
Flanges are typically available in three different sizes. You will get a standard 4 x 3 inch. flange, 4-inch flange, and 3-inch flange. On the basis of material, six different kinds of flanges are available in the market. which include PVC flange, stainless steel flange, Aluminum flange, Cast Iron Flange, copper flange, and brass flange. In addition to that, flanges come in different styles like offset, deep seal, push-tite, slip toilet, etc.
Further, in this article, we will talk about what a flange is, and discuss in detail where each of these flange sizes and types is utilized.
Let’s start with what a flange is.
What is a Toilet Flange?
A toilet flange is a pipe fitting that is used to connect a toilet to the sewer line or drain pipe. It is also used to attach the toilet bowl to the floor. It has a rubber gasket that seals the connection between the flange and the toilet.
There are three main parts to a toilet flange: the ring, the body, and the bolts. The ring is a circular piece that sits on top of the drain pipe. The body is the part that attaches to the floor and supports the toilet bowl. The bolts are used to attach the flange to the floor.
Now that we know what a toilet flange is, let’s talk about its different sizes and types.
Different Sizes of Toilet Flange
Normally, you will find a 3-inch, 4-inch, or 4 x 3 toilet flange. However, some odd-sized flanges with greater or lesser dimensions than the standard sizes are also available.
4 x 3-inch Toilet Flanges
4 x 3 is a standard toilet size that most toilets use. You can easily find this size flange around the town.
As its name suggests, its cross-section varies from top to bottom. The top end has a diameter of 4 inches, while the bottom end has a diameter of 3 inches.
The 4-inches top easily fits the wide-end toilets, and the bottom end fits into the closet bend or drainpipe.
3-inch Toilet Flanges
Another common flange size is 3 inches. This kind of flange has a constant diameter throughout its cross-section i.e. the top and bottom end both have 3-inch diameters.
A 3-inch pipe can handle a large load. However, when you flush the toilet, it has to bear a great amount of pressure.
Keep in mind a 3-inch flange only fits on a 3-inch drain or closet. If the drain size is larger, you will need bushing to fit into the pipe. That forced fitting may affect the toilet’s alignment, and leakage may occur in the future.
It is always advised to buy the flange after considering the size of the toilet and drain pipe.
4-inch Toilet Flanges
4-inch drain pipe is not much common; however, it is also among the flange sizes you will find in the market. Like a 3-inch flange, it also has a constant cross-sectional diameter. The added benefit of a 4-inch flange is that it easily fits in a 3-inch or 4-inch drain pipe.
4-inch toilet flanges are ideal for scenarios when you don’t know exactly about the size of the drain pipe or closet flange. It just slides in, in case the pipe is larger. Or pipe slides into the flange.
Odd Size Toilet Flanges
Sometimes, we need flanges other than the standard sizes. These are called odd-sized flanges. You would be surprised to know that a flange with 7 inches top diameter and 3.5 inches bottom diameter is also available.
Types of Toilet Flange [Based on Material]
As we mentioned earlier, flanges are available in six different materials. each with its advantages and disadvantages.
PVC flanges are the most common type of flanges used excessively in residential and commercial bathrooms. They are cheaper, durable, and easy to install. Moreover, they are also resistant to corrosion and do not rust like other types of metal. However, PVC is not as strong as some of the other materials like Aluminium and stainless steel.
PVC flanges may be completely made of polyvinyl polymer or they may contain a metallic top with plastic. You can easily get them in 3 and 4-inch sizes. If you are considering a cheaper option, you can go with a PVC flange.
Stainless Steel Flanges
Stainless steel is a strong and durable material. Like PVC, they are also resistant to corrosion. They last quite long, even for decades. You would find it interesting that only the ring of this flange is made of stainless, while the base is usually made of brass, copper, or PVC. So, its name is kind of misleading the user.
Numerous designs exist for stainless toilet flanges, but type 304 is by far the most common. It is a chromium (18%) and nickel (8%) alloy. Additionally, there are updated variants available that contain silicon, which prevents the flange from oxidizing. In addition, it is more costly than a PVC flange.
Aluminum, as you know, is a strong and lightweight material. These flanges, like their counterparts, are also resistant to corrosion. Complete flanges or just wax rings made out of Aluminium are also available. The use of these flanges is not much common.
Cast Iron Flanges
They are one of the strongest flanges you will find. However, you can only install it with a copper drain piping. Similarly, these flanges are normally used when the waste pipe is below the subfloor.
They are readily available in all sizes. But being made of iron, they may rust earlier compared to other flanges. They are very heavy, hard, and difficult to install. So, you cannot use them with PVC piping.
Brass is another wonderful option for toilet flanges. The zinc-copper alloy makes them strong, durable, and resistant to corrosion.
Copper is a beautiful material that is easy to install. Copper Flanges are the best corrosion-resistant flange available in the market. They are considered more durable than even brass or iron flanges.
They come in two variants, soft and rigid. The former ones are famous for their easy installation. Being flexible, we don’t elbow joints while using copper flanges. They easily twist and fit into pipes. However, the rigid copper flanges are hard and do require an elbow joint.
Other Types of Toilet Flanges [Based on their Shapes]
Apart from these flange types, you will find multiple kinds of flanges based on their shape.
Offset Toilet Flange
These curved flanges are perfect for openings in strange positions, such as when the pipe opening is positioned too near to the wall or too far from the floor.
The diameter of an offset flange is the same as that of a regular flange; the difference is that the casing of the flange is positioned at a 45° angle. This allows the toilet to be moved away from the wall, which is helpful if the plumbing is too near for today’s standard toilet sizes.
Push-Tite Toilet Flange
The push-Tite toilet flange is made of PVC with a rubber gasket on it. As the name suggests, you just need to push it to install. You don’t need any glue to secure it. Just push it into the drain, and it will get into its place.
Deep Seal Toilet Flange
The deep seal flange is similar to its ordinary counterparts, but it extends into the pipe approximately 12 inches farther than its usual counterparts.
Slip Toilet Flange
This style of the flange is designed to slide over the drain pipe. It needs to be installed using cement.
Slip flange has two types; one-piece and Van Stone slip flange. In the case of a one-piece slip flange, careful installation is required. The flange becomes immobile once it has been cemented into the waste pipe.
Van Stone is a two-piece slip flange. It has a rotating ring that makes its installation easier.
Signs that indicate that Toilet Flange needs replacement?
If your toilet flange turns bad, you will start witnessing multiple signs.
Sign # 1 Toilet Leaks from the base
If you notice that your toilet starts to leak from the base, then it means that the wax ring has cracked or the flange is damaged.
Sign # 2 Bathroom Smells
If you have suddenly noticed a pungent smell of sewer gases rising from your toilet, you need to check if the flange is correctly fixed in its place. If the flange is damaged, it lets the sewer gases into the toilet.
Sign # 3 The toilet feels loose
If the toilet wobbles, that means it is not correctly positioned due to loose bolts or due to the damaged flange.
Push the toilet with your hand, does it move around, or stay still? If it wobbles, that means the flange needs replacement.
How to Install a Flange?
Installing a toilet flange is a long and tedious task. First, you need to remove the whole toilet, then the flange gets exposed. For removing the toilet, you will need to remove its bolts and detach the tank from the water supply. So, we suggest you seek professional help if you think that the flange needs replacement.
We hope that this comprehensive guide on types and sizes of toilet flanges helped you understand the need for a toilet flange and how to identify when it needs replacement. If you think we have missed something, please let us know in the comments below.
Amos Christen graduated with a bachelor’s degree in Interior Design from Drexel University — Philadelphia, PA. Since 2003, Amos has worked with top interior design professionals in this area, including architects and interior/graphic/lighting designers. As a skilled interior designer, Amos Christen is highly versed in fine arts and crafts and uses that to supplement his main area of expertise. He often publishes articles related to home décor on several websites, including Sprucetoilets.com, Sprucebathroom.com, and Mybesuitedhome.com. He also contributes to leading interior design magazines.