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Choosing The Right Size Screws For Toilet Flange

Choosing The Right Size Screws For Toilet Flange

Perhaps it is your first time installing a new toilet. Maybe you are just looking to replace a wax ring or even want to simply replace a few corroded toilet flange screws. Whatever it is you are looking to do, you want to set things up right the first time. There is an old saying “Better to measure ten times and cut once than to measure once and cut ten times”. This is true in anything. 

So, how do you choose the right size screws for toilet flanges? Simple answer. Choosing screws for toilet flanges is a much simpler choice than it may seem. Just pull out and look at the old screws you’re looking to replace. Take those screws to your local department store and anyone in the services department will guide you.

As far as bare-bones simplicity in picking the right size screws for toilet flanges, you have all you need. But on the off chance, the flanges were not installed with the right size screws, to begin with, leading to some malfunctions that lead to you coming here looking for some guidance, we’ll delve into a few things to consider in your choice of proper sizing.

What Size Screws For Toilet Flange?

So you have already pulled out the old, broken or corroded screws you wish to replace. You have then realized they are not the proper type or size screws you need for the toilet flanges either. What do you do? There are a couple of options you have available to you. With a little bit of know-how, you will be over and done with this project in no time at all. 

But here are the things to consider when choosing the proper screws for the job. 

Know What Material You Are Screwing Into

Screws are going to be labeled specifically according to the purpose in which they are used. Your local department store, in the hardware section, will have screws separated by purpose. There will be a row of wood screws, drywall screws and sheet metal screws for example. If your toilet is being screwed into wood, you may want to consider using wood screws.

If the wood board happens to be on the thicker side or there are multiple wooden boards stacked alongside one another. You will want to go with a longer set of screws. 1 1/2 inch screws or longer is usually a safer bet if you are screwing into thicker boards. If the board is more shallow, then 1-inch screws will probably do the job for you. 

Type Of Material You Are Screwing Into

In keeping with the last point of consideration. Once you know what type of material you are screwing into and how thick. You can use that information to look at the screws specifically designed to go into that type of material. Every material has certain types of screws that are often paired alongside it and here are some of the most common.

Roundhead screws, often reserved for machines such as cars, heavy equipment, and serious power tools where you don’t want screws being removed. While Panhead screws are the main screw of choice for driving into sheet metal. The fine thread of the screws shaft makes it apt for running smoothly into sheet metal.

For wood surfaces as previously mentioned. Wood screws, or more specifically Flathead screws, are the screw reserved for this job. Flathead screws have more course threads that stop short of running up the entirety of the screw, unlike the Panhead screw that runs up the entirety of the screw.

The “Drive” Type

The topside or head shape of the screw is often called the “drive” type for the screw. There is a small variety of drive types that cover the host of all jobs you might need a screw. There are Philips Head screws, shaped like a cross. These types of screws are often used for machines, hardware, and hinges. 

There are also Flat Head screws or “Slotted” screws. These types of screws are often reserved for very light, simple jobs such as screwing in the faceplate for a light switch in any room of your house. There are also more specialty screw heads such as Hex Screws. These types of screws are often used as a lock and key. Paired up with an alan wrench that acts as the key.

Tips And Tricks

These are the bonafide tips that you did not know you needed! The extra oomph that will be the wind beneath the wings of the results you are looking for!

Pickup Some Washers Rings

Using a set of washer rings can allow for much more wiggle room if you happen to not have the proper size screws for the job. And if you do have the proper screws these washers will accentuate the strength they can apply to the job at hand. If you are using a set of tightly fitted washers this will provide any screw more surface area to apply even more pressure. 

Doing this can help you out in the meantime, while you wait for your opportunity to get properly fitted screws. Or if you are intending to be lazy this weak, you just saved yourself a little bit of change!

Pre-Drill A Hole Into Wood Surfaces

If you have any experience screwing into a wooden surface whatsoever. Then you will definitely already know how wood has a tendency to split apart when driving a screw into it. By going the extra step to find your drill so you can pre-drill a hole into the block that is slightly smaller than the thickness of the screw you will be able to mitigate the splitting effect. 

By lowering the amount of bend the wood has to give, you will allow for the screw to fully insert itself into the wood more smoothly without being overly concerned with the wood splitting itself apart.

Use Oil Or Bar Soap To Coat Screw Threads

This last one may seem a bit odd, but keeping in line with the same reasoning for pre-drilling a hole into wooden surfaces. You can take an additional step of slicking the surface of the screw threads with soap or oil. Doing this will help you drive the screw path into the wood more smoothly. 

Especially if you are using the more course Flathead wood screws. These Flathead screws can carry a lot of excess friction as they are grinding their way against the wood etching. Coating the thread will lower the friction. 


So there you have it! As was stated earlier. If checking the size of the screws you already have in place does not prove fruitful for figuring out the proper screws you need to have. You can simply take into account the type of material you are screwing into, the type of screw you are using and the thickness of the driving surface. 

By following those tips you will have no trouble whatsoever choosing the right size screws for your toilet flanges. Hopefully, you have found this article informative and helpful. If you keep in mind these recommendations for choosing a screw you will find the properly fitted screw for the job soon enough. 

Learn More

If you are interested, go check out the toilet section on Amazon for any great deals.