How To Seal a Sunroof Permanently? 4 Methods To Follow!

You can seal your car’s sunroof with silicone. Also, using polyurethane auto-glazing sealant or 3M butyl sealant can be a good option. The sunroof can also be permanently sealed by welding. 

This was a brief overview of the multiple processes used to seal the sunroof permanently. This article will explain in detail how to seal sunroof permanently without making any mistakes.

Can You Seal the Sunroof Permanently?

It’s possible to seal your car’s sunroof permanently. Sealing it can be done in different ways. People want to permanently seal their sunroofs for many reasons, like fuel economy issues or leakage issues (1).

How to Seal the Sunroof Permanently?

To permanently seal your car’s sunroof, you can choose various methods. Some methods you can apply yourself, and others require an expert’s assistance.

Before discussing the methods and their applications, let’s take a quick look at their pros and cons.

Sealing MethodsPros Cons
Silicone Sealant1. UV stability
2. Extreme temperature resistance
3. High workability
1. Dirt retention
2. Lower tear resistance
3. Lower abrasion resistance
3M Butyl sealant1. Non-drying
2. Non-hardening
3. Anti-leakage sealant
1. Dissolve if exposed to strong solvents
2. Not high-temperature resistance
Polyurethane sealant 1. Tear and abrasion resistance
2. Chemical and weather resistance
1. Instability
2. Odor problem
3. Not environment-friendly
Welding1. Long durability
2. Weather and temperature resistance
1. Difficult to install
2. Need an expert hand
3. Expensive

Method 1: Sealing the Sunroof With Silicone

You can seal your car’s sunroof using silicone if there is a leak or rust on the metal. Here’s a step-by-step guide to sealing the sunroof shut with silicone. To complete the process, you will need the following tools.

  1. Wax-free car cleaner
  2. Rag
  3. Terry cloth
  4. Caulking gun
  5. Silicone sealant
  6. Mineral spirits
  7. Paper towels

Step 1: Start by cleaning your car’s roof and sunroof with a wax-free car cleaner and a rag. Make sure the sunroof is free of grease and dirt.

Step 2: Let the roof and sunroof dry using a terry cloth.  

Step 3: Before using the sealant, ensure the sunroof is properly closed and locked. Be sure to close all locks and latches and dry.

Step 4: Now, take your caulking gun and fill it with silicone sealant. Use the gun’s handle to cut the sealant tube tip.

Step 5: The final step is to caulk the roof with silicone sealant. To seal the gap between the roof and the sunroof glass, apply a sufficient amount of silicone. 

Step 6: Next, remove excess silicone from your sunroof. As soon as the caulking is complete, you can use mineral spirits and paper towels. The time will be between 5 minutes after the application. 

Summary:

Silicone is the easiest and most popular way to seal the sunroof. 

Method 2: Sealing the Sunroof with Polyurethane Auto Glazing Sealant

Polyurethane sealant is an excellent alternative to silicone sealant for sealing your sunroof. It has a perfect tear and abrasion resistance and weather resistance.

If you want to seal your sunroof permanently, use a polyurethane-based sealer. This kind of sealer tends to last better and longer. 

The application process and the curing time would be the same as the process for silicone.

Summary:

Use a polyurethane-based sealant that serves better and longer.

Method 3: Sealing the Sunroof with 3M Butyl

3M butyl is a non-drying, non-hardening synthetic rubber-based sealing tape. The sunroof can be permanently sealed with this chemical-resistant retrofit anti-leakage sealant.

Aside from leakage, people seal the sunroof to prevent kids from accidentally opening it. Here is how to seal your car’s sunroof with 3M butyls. 

Step 1: Make sure the sunroof is completely closed.  

Step 2: Get a 1/2”x15ft 3M Butyl Autoglass tape for sealing the sunroof.

Step 3: Measure each side of your sunroof glass.

Step 4: Cut out the tape pieces according to the measurements. 

Step 5: Wrap the tape securely around the glass, ensuring there’s no gap between the glass and the frame.

It lasts as long as any other regular sealant since it’s a rubber-based synthetic sealant.

Summary:

To permanently seal a sunroof glass, wrap a  ½”x15ft of 3M Butyl sealant and tape around the edges of the sunroof. 

Method 4: Sealing the Sunroof by Welding 

If you want to seal it permanently, you can weld the roof to fix it. You must remove the glass and cut the roof edges where the glass was installed to seal the sunroof. By doing so, no glass will remain on the roof, which will ensure the roof’s security.

You will require a metal sheet according to the measurement of the sunroof. You need to maintain proper caution and need expertise in the welding process. It’s quite a complicated and time-consuming process.

Therefore, you should take your car to a repair shop that can do the work perfectly.

However, if you still want to seal the sunroof permanently, here is a video instruction you can follow.

Summary:

For welding the sunroof to seal it completely, seek expert help by visiting the repair shop. 

How Long Do Sunroof Seals Last?

How long a permanent sunroof seal lasts depends on how it was sealed. Silicone sealants can protect for up to 20 years when used properly. However, for the sealer to last long, you must apply it correctly.

On the other hand, polyurethane-based sealer lasts 5–10 years. Finally, 3M Butyl Sealant provides you with a 5-year service life.

Sunroofs sealed by welding will last longer than those sealed by other methods. To be precise, it should last as long as your car lasts.

Summary:

The welding process will last longer than any other methods applied.

Things To Keep In Mind When Sealing A Sunroof

It is crucial to keep certain things in mind when sealing the sunroof, no matter what method you use. 

The following tips and tricks will help seal a sunroof more conveniently whenever necessary. 

  1. Make sure you don’t apply silicone sealant in the rain, snow, or heavy fog. 
  2. To protect the rubber from the sun, apply a UV Protectant. 
  3. Make sure there are no clogs on the sunroof drain before sealing the sunroof.
  4. Make sure you have disabled the sunroof motor no matter which method you use. This is because any accidental press to the sunroof switch may ruin your effort and break the seal.

To disable the sunroof motor, drop the switch panel and unplug the connector to disable the roof motor supply. 

Does The Weight Of The Sunroofs Affect The Vehicle? 

Having a sunroof on your car can reduce your fuel economy because of the roof’s weight. There’s about a 50-pound increase in weight when there’s a glass panel sunroof on a normal sedan and 80-pounds. There’s a 120- to 200-pound weight penalty if you have a panoramic sunroof.

Will Insurance Cover Leaking Sunroof?

Yes, but it depends on what caused the leak. For example, your insurance will cover you if the weather causes a leak in your sunroof. But if the reason is because of wear and tear, then your insurance will not cover it. 

Is It Better To Have A Sunroof Or Not?

It is best to have a sunroof if you want a clean and open view. If you do not, then it is totally up to you. You can get a sunroof if you prefer to let more nature into your car cabin. Sunroofs give the cabin a sense of spaciousness. Unfortunately, the cost of cars with sunroofs is higher than those without sunroofs. 

Conclusion

So, now you know the various methods of how to seal the sunroof permanently. The bottom line is that you can permanently seal your car’s sunroof using multiple methods. 

Sealing the sunroof at home will cost less than repairing it in a shop. While sealing the sunroof, take proper precautions, or seek help from someone expert. Feel free to share your thoughts with us if you require further assistance. 

Let’s call it a day until then. Bye bye.

Photo of author

Gary Wright

Hi, I'm Gary Wright, an automotive industry specialist. I'm an installation, repair, and maintenance specialist of automotive sunroofs, moonroofs, and panoramic sunroofs/moonroofs.