How To Properly Apply Silicone Gaskets In Windows, Bathrooms And Kitchens

If talking about silicone gaskets is to mention the bug, let’s do it. Except for the most handyman, some DIYers and even professionals hate sticky and scary silicone.

In this article, I will show you how to seal with silicone sealants, and I will tell you some tricks I use to help you learn how to make silicone gaskets better than good.


Installers, aluminum window carpenters, marble workers, and other professionals use silicone gaskets in their jobs.

A good professional knows how to apply silicone well, like the turtle: slowly, but without pause. They take it easy; it is just one more phase in their trade. On the other hand, many others hate this task, to such an extent that they start to shake when it comes time to open the first pot.

A bad silicone gasket ruins the best of jobs. What is the use of a well-centered window, plumb and anchored, if it is accompanied by a silicone gasket that is a dread? Also, silicone is not only aesthetic; it also affects insulation and waterproofing. Therefore, the silicone must be applied well: it is as important a step as any other.

Working silicone well is not comfortable, but it is not difficult either: like everything else, you have to learn how to do it. In this article, I detail how to make practical and aesthetic silicone joints.

How to make that perfect silicone gasket

Oddly enough, a perfect, professional-looking silicone gasket only requires two steps:

  1. Apply the right amount of silicone in the right place
  2. Work the joint and remove the correct amount of excess silicone: no more, no less.

If you apply more silicone than necessary, it will be challenging to collect the excess without damaging the joint. And if you fall short, then the same. In the latter case, the cooperative will look porous and half empty. 

So let’s go to the beginning: apply the right amount of silicone in the right place.

What do you need to apply the silicone well?

To apply the silicone well, you need three things:

  1. Make the correct cut in the mouthpiece of the silicone bottle
  2. professional silicone gun
  3. A minimum of practice

Even if you haven’t applied silicone in your life, you can be making perfect shoelaces in just over half an hour. Of course, provided that the two previous steps are fulfilled. Otherwise, you will never seal well with silicone.

How to cut the mouthpiece of the silicone bottle?

Every master has his trick. I prefer to cut the nozzle of the cannula perpendicular, I mean without a slope. Others do it obliquely, I wouldn’t say I like it, but it works the same.

I make a paragraph here to tell you a trick. Cutting the silicone mouthpiece well is so essential that you should keep that cannula for all the joints that you are going to make with the same thickness if it turned out well.

Professionals wear the silicone tubes one after the other, always using the same mouthpiece. With this, you not only get the joints to be the same, but you will also achieve a lot of additional nozzles, which you may always need.

How much to cut the nozzle?

This is something that is achieved practically, that is, trial and error. There is no other.

The idea is the following. If you cut the mouthpiece less than necessary, the silicone cord will be thin, and it will take a long time to extend it. When you pass your finger, potato, spatula, or boat (I will talk about it later), you will not make contact with the silicone, and the joint will be wrong. Poor. Little crowded. With the risk of leakage. Ill. Looking bad. Work of a botch.

On the contrary, if you cut the mouthpiece too much, the can empties too quickly, and you run the risk of wasting the silicone. And quality silicone doesn’t come cheap.

How much to cut then? Honestly, don’t worry about it. Stick with the ideas in the previous two paragraphs. If you’ve never applied silicone, it won’t be perfect the first time. Correct the cut according to the suggested clues.

It will also be when you collect the silicone that you will discover if you have applied the correct amount. The following times you will do better. As I say, this is empirical and is achieved with practice.

How to apply the silicone?

It will help if you spread the silicone with the gun tilted at such an angle that you have good visibility of the bead. At what angle? The right one. And which one is correct?

Grab a pen and paper and start writing! More or less, the position of the cell on the report is the angle you are looking for. Instead of writing, move your hand laterally in the direction of writing: that is the gesture. If you are left-handed, move your hand in the opposite direction.

Practice on paper or with a glue gun (without pressing the trigger) to improve pulse control.

Of course, in addition to the nozzle’s size, the thickness of the bead is also influenced by the speed of the gun. And this too is a matter of practice.

Let’s recap. You already have (better, you will have) the practice to spread the silicone, and soon you will know how to cut the nozzle. You are missing point two, which is essential: a professional silicone gun.

The advantages of using a professional silicone sealant gun

In my case, it wasn’t until I bought a professional silicone gun that I found aesthetic silicone gaskets. What is considered a professional silicone gun? We go in parts.

First, some pistols are rotating. It is useful to work with the mouthpiece at an angle: you can orient the cannula without turning the can. Most professional silicone guns are rotating.

On the other hand, there are electric silicone guns. A professional installer which does nothing more than apply silicone for hours needs one of these. We are talking about spending 100 silicone cartridges a day! Of course, you can get perfect silicone gaskets without a stun gun. Also, sealing the toilets in your bathroom, windows, or kitchen counter does not take as much.

What characteristics should a good silicone gun have?

In my opinion, a good glue gun must meet two requirements :

  1. You must apply the silicone gently, progressively, and without sudden jumps
  2. The silicone must not drip when the trigger is released

The first point speaks for itself and is not worth elaborating on. The cheapest, mediocre silicone guns apply the silicone cord in fits and starts. This forms irregularities and lumps that are later difficult to correct. Also, they waste more time when extending the meeting. Therefore, an essential requirement of the glue gun is that its mechanism works smoothly.

The second point is as important as the first, although it may not seem so. Why should the silicone not drip? First, it is a hassle. Second, if the silicone builds up at the tip when pausing, resuming the seal, the bead deforms.

The above is true unless you have a paper towel to clean the nozzle when resuming a bead. This is the trick that I used before buying the professional anti-drip silicone gun.

What silicone gun to buy?

If you still do not have a professional gun, what you should look for when buying your silicone gun is an anti-drip device. We go in parts. The one that I show you in the paragraph below is a cheap silicone gun without a drip.

This type of gun is not only leaky, but it is also fragile. The welds that join the side plates to the head ring pop out as soon as you try to use a silicone bottle that has gone hard. Trust me. I tell you from experience. This is the type of glue gun you should avoid at all costs :

How does the anti-drip system of a silicone gun work?

What is anti-drip, and how does it work? There are several types of drip systems. The anti-drip device is an ingenious double-thrust mechanism that activates a second spring that acts as a shock absorber when pressure is applied and is released when you release it. This means that the spring makes the plunger go back a few millimeters when you remove the trigger.

If the glue gun is good, the anti-drip system is effective. It is a mechanical marvel that allows you to leave the gun parked at any time without finding yourself after a few minutes with a typical squirt of silicone hanging from the nozzle.

How to recognize a pistol of this type? You can recognize it because, on the handle, it will have some additional set of springs and plates or another mechanical system that is responsible for preventing the rod from continuing to press the silicone.

Some seem much more complex and elaborate than the typical silicone guns of a lifetime. Others look very similar but more robust.

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