Square Shaped Toilet with Concealed Fixings

The toilet seat is one of the most important parts of a toilet. It is where you sit, and it needs to be tight enough that it does not move around, but loose enough that your weight does not cause cracks in the porcelain surface.

These days, many toilets are designed so that the seat is fitted with concealed fixings, not only is this done for aesthetic reasons but also for hygiene reasons. Have you ever cleaned a toilet and seen all of the grime underneath around the bolts?

So, how do concealed fixings work? and how do you tighten a toilet seat with concealed fixings? This article will show you how to tighten a toilet seat with concealed fixings so that you do not have to worry about cracking or breaking anything when adjusting the placement of your seat.

What are Concealed Fixings?

Concealed fixings are exactly that – concealed. This means that they are hidden from view and the actual fix is made internally for a cleaner looking finish.

There are a few different types of concealed toilet fixings to choose from, but they all have the same idea in mind – cover up where you tighten the toilet seat so that it cannot be seen.

How do Concealed Toilet Seat Fixings Work?

With regards to toilet seats, the concealed fixings are usually a screw or nut that are attached to a rubber plug that expands as the toilet seat is tightened therefore fixing the seat in place.

These fixings are much shorter than older style bolts and prevent them from poking all the way through – which is one of the most common reasons for cracking porcelain surfaces on your toilet.

How to Tighten a Toilet Seat with Concealed Fixings?

There are a few different designs of concealed fixings so the tool that you will need will depend on which type of fixing you are going to be tightening.

In general, for almost all of the fixings you are likely to have, you will need either a Phillips screwdriver or a small cone spanner (cone spanners are like normal open-ended spanners but flat like a pancake).

Step 1 – Lift the Seat

I am presuming that you have already checked to make sure that the fixings are indeed concealed and that there are no bolts underneath the rim.

If so, the first step is to lift the toilet seat which will often give you an idea of what tool you will need.

Many toilet seats with concealed fixings will have a button located near the hinges somewhere to allow you to lift away the seat just leaving the fixings in place. If it has, gently lift the seat away – if not, this means that the fixings could be attached to the seat.

Step 2 – Remove the Caps

The fixings will usually be covered by a chrome cap, again, in most cases, these will just lift up too.

Some caps will lift off completely exposing the fixing underneath but others (especially those with fixings attached to the seat) may not lift up and have a small opening at the front.

Step 3 – Tighten the Concealed Fixing

If you have lifted off the caps and exposed the fixing and can see the screws, these can be tightened.

If, however, you have one of the fixings that have a small opening in the cap or has caps that just lift a small way and do not come off, you will need to use your small cone spanner which will usually come with the seat.

Inside the small opening or under the partially lifted cap, there will be a small nut that can be tightened.

What if the Fixings are Still Loose?

If for some reason the fixings remain loose even after tightening, there could be a couple of reasons.

Firstly, the fixings could be too small for the hole they are seated in. In this case, the fixings are inadequate and were probably not installed in the right size, to begin with.

Secondly, the fixings may have degraded over time and the rubber is no longer expanding inside the hole to ensure a good fix.

Where to Get Concealed Toilet Seat Fixings?

Concealed toilet seat fixings are quite easily found, you can find them at your local plumber’s merchant, Screwfix, B&Q, etc. Or you can buy them online and have them delivered straight to your door.


As you can see, tightening toilet seats with concealed fixings is easy when you know how to do it.

If you have attempted to tighten the fixings and the seat has remained loose, you will have to investigate further, the best way to do this is to remove them completely and see if they need replacing.

Plumbing Wizard Tips

“We advise that when doing this job, you wear gloves – there are lots of invisible nasties in toilets – even around the seat!”

“If the rubber no longer expands inside the hole – it is cheap, quick and easy to just replace the fixings!”

“Locate the button on the seat so it can just be lifted away from the fixings leaving you space to work!”

“Be careful when checking to see if the caps can be removed – if they are fixed to the seat, you may damage them if you try and force it!”

Frequently Asked Questions

What does Top fixing mean on a toilet seat?

Top-fixing toilet seats are toilet seats that are fixed in place from the top. This means that the fixings are usually concealed internally within the pan itself meaning that they are hidden from view.

Can I use concealed fixings on an old-style toilet?

Yes, concealed fixings can be used on any style of toilet although you will need to ensure that the fixings are the correct size for the hole that they are required for.

Are toilet seat fixings universal?

Most standardised toilet seat fixings are universal although some toilet seats may come with specific fixings and hinges depending on the design of the seat.

About Me

I’m Lee the Plumbing Wizard. I’ve been a plumber for over 40 years and have seen it all. People used to call me a magician because I could fix things so easily – hence the name Plumbing Wizard.
I’m always happy to help out a fellow tradesman or woman, so if you need any advice or just someone to talk plumbing with, don’t hesitate to get in touch!

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