How to Replace a Toilet Seat or 'Lid' (by Capitan Farloc)

Indice

Is your toilet seat broken, loose, or just outdated? No worries! Replacing a toilet seat is one of the easiest bathroom DIY jobs—and you can do it in just a few minutes with basic tools. In this step-by-step guide, we’ll show you how to remove the old one and install the new one properly, with helpful tips to avoid mistakes and make sure it fits perfectly. Whether it’s for style or necessity, you’ll be ready to tackle the task without calling a plumber!

The Toilet Seat or "Lid"

The toilet seat (also commonly referred to as the "WC seat") is one of those accessories that are relatively straightforward to replace.
However, that doesn't mean it's a task to take lightly. In this short guide, I’ll explain step by step all the precautions you need to take to carry out this operation in the best possible way. Firstly, I must clarify that these instructions refer to universal standard seats.
Some manufacturers of bathroom fixtures provide specific seats for their WC models, and in those cases, the fastening system might be quite different.
I’d also like to mention that if you’re thinking about repairing your old toilet seat instead of replacing it, there’s a helpful article on this site with some useful tips for fixing the most common types of damage. You can find it here: How to Repair a Toilet Seat or Lid (by Capitan Farloc).

And now, after all these introductions, let’s get to work!

Removing the Wing Nuts

The first step is to remove the supports of the toilet seat that needs replacing. These are secured with wing nuts, also commonly referred to as "butterfly nuts.".

To remove the toilet seat, you must first remove the wing nuts that hold it in place.

These wing nuts are generally made of plastic, quite large, and feature two "wings" (hence the name "wing nuts") that allow them to be turned quite easily by hand.
However, over time, the threaded stud onto which the nuts are screwed may have rusted, making removal more difficult. I strongly recommend using pliers and a generous dose of penetrating oil to loosen the nut more easily.
Once the old toilet seat has been removed, it’s good practice to thoroughly clean any buildup or deposits that have formed under the hinge mounts.

The threaded pins on the old board will most likely be rusted.

Aligning the Hinges of the New Toilet Seat

To align the hinges so they match the WC holes, place the new toilet seat upside down on the WC.
When viewed from underneath, each hinge has a screw (usually left quite loose) and two threaded holes.
By observing the old hinges, you’ll need to check whether the threaded studs were screwed into the central holes or the outer holes of the hinge, as you’ll need to replicate this arrangement on the new seat.
For now, focus on adjusting the hinge axes by rotating the lower part (if they don’t turn, you’ll need to loosen the screw slightly) until the threaded holes line up with the WC holes. Once in position, tighten the screws securely to fix them correctly.

We register the hinges of the toilet seat

Screwing in the Threaded Studs and Placing the Gaskets

Next, screw in the threaded studs provided with the toilet seat into the corresponding threaded holes. Make sure to use the correct holes.

We screw the threaded pins onto the hinges of the toilet seat

Placing the Gaskets on the Hinges

On top of the hinges, threaded onto the studs, you’ll place the gaskets that are also provided with the toilet seat.
These gaskets usually have a specific orientation that must be respected: the stepped side should face the hinge, while the completely smooth side should be directed upwards and, once the toilet seat is mounted, will be in contact with the porcelain of the WC.

We insert the gaskets supplied with the toilet seat

Attaching the Toilet Seat to the WC

Now, turn the toilet seat over and insert the two threaded studs into the designated holes on the WC.
Next, in sequence, first fit the conical washer with the pointed side facing upwards towards the WC hole, followed by the new wing nut, which can be easily screwed on by hand.
The conical washer will naturally settle into the hole, but once both nuts are tightened, it’s a good idea to move the toilet seat laterally in both directions to aid the adjustment process.
After that, tighten the nuts further until the piece is securely fixed. For the final tightening of the nuts, you can use pliers, but be careful not to apply too much force, as this could damage the plastic threading of the wing nut.

We fit the wing nuts and tighten to lock the board

Well, the Article is Now Complete, I hope it has been appreciated and, most importantly, useful to someone.

Thank you for following along!
Luciano (Capitan Farloc)

Warning!

The advice and instructions provided on this site come from hobbyists rather than professional technicians, meaning there is no guarantee that they are accurate or represent the best solution.
Additionally, using the tools and techniques described here should be done with careful consideration of one’s own abilities.
These articles assume that the tasks will be performed by individuals with the necessary skills and knowledge to use the required tools safely, without risking harm to themselves, others, or property.
Therefore, the owners of this site cannot be held responsible for any direct or indirect damages resulting from the application of the content found here.
Before undertaking any DIY activity, it is strongly recommended to read the Safety Notice, which provide a basic (though non-exhaustive) list of precautions to follow.

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