How to Replace, Fit or Fix a Toilet Seat – How to Change or Attach the Most Common Types of Loo Seat

Summary: How to fit a toilet seat; we cover all the common types. Learn how to replace a toilet seat, how to recognise the type of toilet you have and how to remove the old seat. We'll show you what tools you need whether you’re fitting a new loo seat or simply fixing the old one. We cover how to solve the most common loo seat problems; annoying wobbly, sliding toilet (or loo) seats, seats that keep falling forward and won’t stand up, or loo seats which are not positioned correctly on the pan or bowl.

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There is a large array of toilet shapes on the market today and many shapes of seat to go with them. Fitting a replacement toilet seat can be a little tricky to the novice, however if some simple rules are followed, it is not difficult to do.

Typically the toilet seat is fixed to the toilet pan by two long screws that go through the pan using the holes supplied by the manufacturer. In the cheaper models, the screws are made from plastic, the majority are made from steel and the most expensive come in stainless steel or brass. Due to the wet environment, plated metal fixings can corrode quickly.

What Type of Toilet do I Have?

Modern toilets have standard hole centres. Replacement toilet seat kits usually have adjustment to allow fitting to the older or non standard types as well. It is essential that the new seat is supported by the pan at all the contact points.

Most toilets are basically ovoid (oval) in shape when looking down from the top or in plan view. Some are round and there are some fancy ones that have a “square chin” design to the front. There are also seat fixings to cope with back-to the-wall pans, where you cannot get access to the nuts to secure the seat from underneath.

The most common toilet shapes are:

The most common shapes of toilet seat

The most common shapes of toilet seat - from left to right, the Round Nose Toilet Seat, the Traditional Pointed Nose Seat and the D-Shaped Toilet Seat

You will need to measure up your toilet bowl so that you can be sure that the seat that you buy will fit. These are the key measurements that you need, although most seats are adjustable so that they will fit the most common toilet bowl shapes.

Areas to measure on yout toilet for a new toilet seat

The key areas to measure on your toilet when looking to buy a new toilet seat

Key Toilet Seat Measurements:

  • Measure the distance between the fixing holes. This is typically a standard measurement of 155mm, but it is worth checking
  • Measure the width of the bowl where it is widest
  • Measure from the very front of the bowl back to an imaginary line joining the two seat fixing holes

With these measurements you can then make sure that you get the right sized toilet seat.

The mid-range priced seats (around £12.00 - £25.00, June 2016) tend to be produced in timber or can also be available in MDF coated in a plastic and typically with a pattern, although this is not always the case. These seats come with a multi-adjustable set of fixings, typically with gold finish or silver/nickel finish.

If you are thinking of changing your toilet from a close coupled to a low level toilet, take a look at the project we have on this, the old seat may not fit the new loo.

Loo Seat Hygiene and Toilet Health and Safety

Health and safety must come first! The toilet is obviously a place that can harbour harmful germs and is a source of potential infection therefore precautions should be taken before starting the job.

It is wise to first use an anti-bacterial spray which kills most bacteria and fungi, such as E.coli, Salmonella, Listeria, MRSA and Campylobacter as well as most known viruses. They cost around £2 (price taken in June 2016) and are widely available from chemists and supermarkets.

Gloves can be worn for protection against bacteria when changing a loo seat, but this is not always practical. The disposable, thin type of latex gloves tend to tear and split. The more robust gloves, depending on the type, numb the sense of “feeling” what you are doing.

If you prefer to work without gloves, first start by squeezing a little barrier cream onto your hands and massaging this in all over both hands back and front.

Have some anti-bacterial cleaning spray to hand for cleaning the pan when the older seat is removed and before the new one goes on. The same cleaning agent can then be used when washing your hands after the job is done - assuming you are not sensitive to such cleaning chemicals. Always test for this, if you are not sure or have not used the product before.

What Tools do I Need to Fit a Toilet Seat?

Depending on the type of seat fixings, tools may not be needed. However it is probably best to get some basic tools together: pliers, a set of spanners or a small adjustable wrench may be required. For the metal fittings, it would also be handy to have a couple of 6mm nuts available.

You might be simply changing the fittings of the toilet seat, which can be bought separately. This means that you can replace this and keep the seat should you want to. Generally seats don’t make that much difference to the overall cost that people tend to replace the whole seat nowadays.

If you need to get hold of a fixing kit, you cansearch Amazon for Toilet Seat Fixing kits here. The instructions for fitting are the same as if the seat were provided, except that you should attach the seat first.

Stanless steel toilet seat fitting kit

Typical stainless steel toilet seat fitting kit that includes hinges and bolts

Don't forget the loos seat itself - Of course you also need to buy your seat. I would recommend browsing the net for ideas or again going to Amazon for a pretty comprehensive range. Most local bathroom shops will have a small range too.

Removal of the Existing Toilet Seat

In order to remove the existing seat from the toilet you will need to get down on the floor so that you can reach up under the back of the toilet bowl. It is often quite a tricky job and not a very pleasant place to be, but remember that this is how it was put on so you will be able to get it off!

Remove toilet seat wing nuts

The wing nut that needs to be removed to remove your loo seat

Try to look and feel for a plastic winged nut under the pan (in most cases this will be plastic, but in some situations could also be metal). Sometimes you are luck, as should below and this is easy to get to, but in other case it can be very awkward to reach.

By removing both of the winged nuts, the seat can be lifted away.  The pan can then be cleaned with the anti-bacterial cleaning spray.

Wing nuts holding seat to pan

Wing nuts holding toilet seat toilet pan

With this toilet design the wing nut that needs to be removed can be easily seen. Sadly they are not all like this! As you can see once the nut has been removed the rubber washers will simply fall away and then the seat will lift off.

Fitting or Replacement With a New Loo Seat

Refitting the replacement seat is basically a reversal of the removal process. It is important to ensure the seat sits evenly and on the perimeter of the toilet bowl. Make sure that the nuts are secure but not overly tight, as these plastic screws will not take a lot of punishment before they will either give way and strip the threads or snap.

Manufacturers tend to fit the brackets to the 2 part seat assembly. It is then a simple matter of fixing the short piece of studding to the underside of the brackets and combined with a cushioning washer, the studding is secured with a vinyl nut, secured from underneath.

The tricky bit is, especially with close-coupled suites, to ensure that the adjustment of the seat allows for both sections to be lifted and leant against the cistern whilst also allowing the seat to be supported at all contact points to the top rim of the pan.

A further problem with this type of fitting is that with so many adjustable parts, it is easy for movement to occur, thus producing a wobbly seat.

Top Tip from the Doctor:

A tip you may find useful is that having got the adjustment correct, before securing the seat to the pan, note the positions and then unscrew the main adjusting screws and coat the threads with a proprietary thread seal such as Loctite Thread Seal or failing that, use white correction fluid such as Tipp-Ex.

If used quickly, this can be an excellent thread seal and sufficient tightness of the screws will restrict movement. It is important when using metal fittings that the plastic cushioning washers and the vinyl nuts are used underneath to avoid scratching or marking the glaze of the pan.

Parts of the Toilet Seat

The key parts of a toilet seat are show in the diagram below. It is helpful to understand these parts and how they interact to keep the seat on the loo, or stop it wobbling or sliding.

Parts of a toilet seat

The key parts of a toilet seat and its fixings

Step By Step Guide to Fitting a Toilet Seat

Follow these steps to get your seat fitted correctly:

  1. Adjust the Hinges – Most seats allow you to adjust the hinges using a locking screw below the hinge, passing through the hinge plate. Make any adjustment necessary then tighten the screw. Typically there are three adjustments that you can make:
    • Fine adjustments can be made by rotating the hinge plate; this ensures that the fixing bolts can be adjusted so both will go into their respective holes in the toilet pan or bowel
    • To adjust the position of whole seat forward (or backwards), it is possible to turn both the hinge plates 180o. This moves both the front of the seat is it over hangs or does not reach the front of the bowl. It also moves the hinge forward so that the seat (Lid and Ring) can rest against the cistern without falling down
    • In some toilet seat fixing brackets there are other holes into which the fixing bolt can be screwed into, this has the same effect at turning the hinge plate as described above, but allows further adjustment which would not be possible otherwise. In cheaper seats the fixing bolt is prefixed so this is not an option
  2. Moving the position of the toilet seat hinge

    Altering the location of the fixing bolt in the hinge plate can move the position of the hinge forward

  3. Tighten the Hinge Locking Screw - Even if you don't adjust the hinge, tighten the screw! If not tight this will work loose further and cause the seat to become loose and wobble and slide on top of the bowl, which is annoying. And the only solution is to remove the seat and tighten this properly. Most people forget to do this in the excitement of fitting their new seat!
  4. Ensure that the Fixing Bolt is tight, if it possible to be moved
  5. Place the seat and fixings on to the toilet, with the ring and lid lowered. If the hinge plate is metal, there will be a plastic or rubber washer which will and must sit between the pan and the metal plate. This reduces corrosion and most importantly stops the porcelain becoming scratched or damaged
  6. Fit the washers and fixing bolt. This can be very fiddly, but make sure you get them in the right order, as there should be no metal pressing on the ceramic of the pan:
    • Rubber or plastic washer – to protect the pan
    • Metal washer (if there is one) – to spread the pressure
    • Fixing Bolt at the bottom – holding everything on.
  7. Tighten the fixing bolts – after a few days you will need to return and tighten the fixing bolt again. The rubber or plastic will become compressed and therefore allow a little play in the fixing

Toilet Seat Fitting Methods for Various Types of Seat

Here are some of the more common other types of loo seat that you are likely to find:

Toilet Seat with Hinge Bar and grub Screws

Another variation of seat fitting involves brackets that fit through the pan in the conventional manner, but with a variation that they also incorporate a spigot that locates with a metal bar that acts as the hinge.

This bar has 2 blind holes and the method is to locate the spigots into the blind holes which also incorporate a tiny grub screw with an Allen head. A tiny Allen key is required to secure the grub screws to the spigot.

It is quite fiddly as grub screws face the cistern and therefore one cannot see these grub screws once the seat is in position.

Slow Automatic Closure Toilet Seats

Another variation of modern seats involves a slow automatic closure. It is important to note that the brackets that come with these kits are left hand/right hand and to follow the manufacturer's instructions very carefully.

To be effective, these seats cannot be raised and leant against the cistern with an angle over 110 degrees, therefore they may not fit in every location.

Back to the Wall Pan Toilet Seat

There are speciality toilet seats to suit the back-to-the-wall pan, where access to the underneath of the pan is denied.

The seat brackets for this type of eventuality involve a one-piece expansive fitting similar in principle to a cavity wall fitting, where the securing screw is encapsulated by a long rubber grommet with the securing nut at the end.

The method is to fit the rubber grommet into the pan holes and tighten the screw that engages with the nut and as one tightens the nut is drawn up by the screwing action that expands the rubber grommet, making it tighten within the hole in the pan.

This is a very good and well thought out solution for this eventuality and saves having to withdraw the pan from the wall, where re-sealing is difficult.

Toilet Seat Problems

There are 3 main complaints that we hear about toilet seats, and generally they are easily dealt with (if you seat is a reasonable quality):

My Toilet Seat Slides, Wobbles or is Unsteady

This is because something is loose. There are a number of options:

  1. The Hinge Locking Screw is loose – please see step 2 in the fitting instructions above. Commonly this (or it's equivalent) is not tightened
  2. The fixing bolt needs to be tightened – this may have worked loose or the washer has become more compressed allowing some play into the fixing bracket
  3. The fixing bolt or washer has failed – this sometimes occurs with cheaper seats with plastic fixing bolts. They can be tightened but typically it will fail again

My Toilet Seat Falls Down Whenever I Stand it up Against the Cistern

This is because the hinge is too far back. This can be easily fixed by adjusting the hinge position using the 3 options described in step 1 above.

For a man this is one of the most annoying things in existence – you know how we cannot multitask! Thankfully the solution is quick and easy.

My Toilet Seat is too Far Back to My Legs Touch the Bowl when I Sit on the Loo

This is because the hinge is too far forward. The solution is exactly the opposite e of above – the hinge needs to be moved back rather than forward. If the hinge cannot be moved back or if doing so causes it to fall down when raised then you have the wrong size seat. You will need to get the right size seat for your bowl.

If you have any other bathroom or toilet related problems we have a list of toilet related project pages which explain everything from how to fit a new toilet to how to fix a toilet that wont flush to how to mend a push button toilet cistern.

This is the end of your “Toilet Training”! By know you should feel confident to remove, adjust, fix and fit any type of toilet seat. It can be a fiddly job, but replacing a loo seat is a job that anyone should be able to do.

Don't fancy doing this project yourself? We work with Checkatrade to ensure that we recommend only reliable and trustworthy tradesmen.

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