The Drying Time of Roof Tar: What to Expect?

Generally, roofing tar takes about 8 to 24 hours to dry completely. Depending on situations and factors, the drying process can take more or less time.

Building a roof can be challenging, just like renovating an apartment. Roof tar is a principal element suggested by experts.

It’s used to make your roof durable, water resistant, and heat resistant, preventing growing molds from damping. But, if not applied appropriately, all the hard work for roofing tar will go in vain. In this article, you will learn how long roof tar takes to dry, the pros and cons of roof tar, the correct method of applying roof tar, etc.

Roof tar image

How Long Does Roof Tar Take to Dry?

Roof tar can take anywhere from 8 to 24 hours to dry. The duration of tar drying is dependent on some circumstances. The factors include- Appropriate temperature, which fluctuates from 21 degrees Celsius to 36 degrees Celsius; damp weather, including rain, humidity, and dew; well-prepared roof for applying roof tar; correct types of equipment to apply roofing tar; seeking professional help, etc.

What is Roof Tar? 

Roof tar is a substance that is either generated from coal or wood and used as the primary roof coating. It is a sustainable element that creates a water-resistant layer to save your home from dampness and prevent the walls from sweating yellow to fungal growth. Roof tar is also sun resistant, preventing you from harmful sun rays. 

Pros and Cons of Roof Tar.

Like every other thing, roof tar also has its pros and cons. Before applying roof tar, keep these good and bad aspects in consideration. 


  • Roofing tar can make your roof structure more durable.
  • It is UV resistant that protects you from dangerous UV rays.
  • Roof tar makes your home waterproof and prevents dampness.
  • It works amazingly for flat surfaces.
  • Roofing tar is cost-effective.


  • You must apply roofing tar in specific weather. 
  • It can be toxic to your health and cause lung problems. 
  • It can cause more damage to the roof if not applied appropriately. 

The Appropriate Weather for Applying Roof Tar.

The too-hot or too-cold environment is not suitable for roofing tar. Fall or spring is the perfect season for applying roof tar when temperatures usually stay around 21 degrees Celsius to 36 degrees Celsius.

You can apply roof tar when the temperature is 21 degrees Celsius or lower than that. Still, it will not dry until it reaches 36 degrees Celsius. 

The dryer your roof is, the perfectly you can apply the tar. Since tar is already a wet element, coming in contact with more wetness or dampness will ruin its workability.

If your roof has snowfall or raindrops, clean them and wait until it is dry before applying roof tar. If the roof is dry but too hot, do not apply the tar, as the hot temperature can make the tar too thin and hard to work with.    

How to Apply Roofing Tar?

Inspect the roof surface first.

First, inspect your surface. You cannot apply roof tar on uneven, damaged, or cracked roofs. Ensure the roof is flat and has no cracks or holes. If it has any damaged area, call a professional and repair it before applying tar.

Let the roof get warm.

As mentioned earlier, you cannot apply tar if the roof is too hot or too cold. Wait until your roof gets a little warm. The warm surface will make the tar application easier. The roof could take around an hour to warm in the sun.

Heat the tar.

Since tar is a sticky substance, working with tar without heating will be hard. You can leave the tar in the sun or apply hot air to heat it and make it liquid until it meets the required consistency. Make sure the consistency is easy to work with.  

Clean any dust from the roof.

The roof might have dust, debris, dried leaves, and bugs. Remove the specks of dust and clean the roof surface properly; otherwise, applying tar over the debris will leave it rough and unpleasant. 

The dust and debris will also not let the tar stick to the roof surface and not prevent your roof from leakage. You either dust off the roof or rinse it with water. Ensure the water has dried properly before applying tar.

Apply roof tar.

Use a roller to apply the tar. Add tar from the edge and keep moving to the roof’s entrance. Apply even layers to cover the whole roof area. Avoid using the roof until the tar dries completely. Ask for an expert’s help if you can’t apply the tar yourself. Purchase the best quality tar. Check reviews and ratings before purchasing it.

Here’s a great suggestion we found for you at Amazon regarding roof tar.

How to Measure if My Roof Tar has Dried?

You can measure if your roof tar has dried or not based on the weather under which you have applied the tar. If the weather is a little hot or warm, the tar will dry within the time mentioned in your packaging, usually around 8 hours. If the weather is cold, your roof tar will take more time to dry; it could even take 24 hours to dry completely.  

Alternatives of Roofing Tar.

Rubberized tar.

Rubberized and regular roof tar have similar functions, but rubberized tar has some additional advantages. It is more durable in rainy and damp weather. If you want to apply roof tar in rainy weather, rubberized tar is an excellent substitute for regular roofing tar.

Tar paper.

Many companies have produced tar paper to use instead of roofing tar. Tar paper works just as fine as liquid roofing tar. Some benefits of using tar paper instead of roofing tar are that you can apply the tar paper under any weather and don’t have to wait hours for the tar paper to dry.

tar paper on house roof image

Roof cement.

You can use roof cement instead of roof tar. Its application is effortless and dries faster than roof tar. However, the most significant downsides of roof cement are it is more expensive and less UV resistant. 

Frequently Asked Questions (FAQS)

How long does tar take to harden?

Tar takes about 24 hours to dry. You can walk over the tar after a day of applying, but avoid wearing pointed shoes and putting heavy things on it as they can leave marks on your tar. 

Can you use roofing tar in the rain?

Yes, you can use roofing tar in the rain, but only if you are using rubberized tar. Rubberized tar is more water resistant and can stick to the roof surface even in heavy rainy weather and damp environment. 

Can roofing tar resist leakage and heat?

Roofing tar can stop leakage since it is water-resistant. When the tar is completely dried, your roof will be waterproof and heat-proof. Thus water won’t leak anymore from the roof, and your house won’t be hot. 

How long does tar last on a roof?

The average lifespan of tar is 25 years. If the tar quality is excellent and proper maintenance is ensured, it can last up to 40 years. So purchase the tar carefully, as it is a long time investment.

Is roof tar toxic?

Yes, roof tar can be toxic and cause lung irritation and breathing difficulties, especially in asthma patients. So people who have asthma should avoid staying around tar and prevent inhaling tar vapors.

How do you get rid of the tar smell from the house?

You can get rid of the tar smell from your house by sprinkling some baking soda around the corner. Sprinkling baking soda on your carpet will absorb the unpleasant tar smell and even make your carpet smell nice.


Usually, roof tar takes from 8 to 24 hours to dry, depending on some circumstances. Tar doesn’t only make your roof waterproof and heat resistant but also gives your house an attractive look. To make your tar durable and efficient, you must consider several facts. Consider the following factors before applying tar to your roof.

  • Ensure the temperature is between 21 to 36 degrees Celsius.
  • The weather should not be too hot in summer or too dry in winter.
  • Experts suggest fall or spring for applying tar.
  • Prepare and clean your roof correctly for applying tar.
  • Use the right tools for applying tar.
  • Avoid using the roof until the tar dries completely.