One common mistake I have seen homeowners make is only worrying about their flat roofs when they leak. Unfortunately, this costly mistake threatens the durability of your roof.
So, what should you do? I always recommend roof coating for a flat roof every five years to increase durability and reduce expenses. But, there are hundreds of roof coats available in the commercial market today.
So, how do you determine the best roof coating for a flat roof? If you are in this dilemma, worry not.
As your most trusted roofing solutions partner, I have prepared this guide to let you in on the top 7 products for your flat roof. You will also learn about different flat roof coatings, tips on selection, and applying roof sealant.
Best Roof Coating for Flat Roof Reviews
1. Heng’s Rubber Roof Coating – 1 Gallon
If you are looking for the best and most versatile flat roof coating, you have an ideal solution in Heng’s Rubber Roof Coating. Whether you are looking for a preventive or reparative coating, this product won’t disappoint you even in the slightest way.
My favorite part of this product is its ease of application. It’s liquid rubber, so applying it will be a breeze. However, you may need to apply two coats or more to achieve the desired thickness.
This product is also highly flexible ensuring that it can expand and contract in extreme temperatures. So, you don’t have to worry about sudden cracking or degrading when the weather changes or when you make slight movements on a flat roof coating.
Its UV radiation and weather-resistant capabilities make it resilient enough to protect your roof surfaces from UV degradation. And you don’t have to worry about its durability as it is made with materials that can withstand high heat and cold weather.
What about the price? Well, most times, we often have this misleading thought that a quality product will be pricier. But it’s not always the case as this product is quite budget-friendly.
And if you are a passionate environmentalist, you will fall in love with this product’s non-toxic nature. It does not pose any risk to the environment.
Pros
- Highly reflective and flexible
- UV rays and water-resistant
- Easy to apply
- Environmentally friendly
- Durable and budget-friendly
Cons
- Require multiple coats to achieve desired coat thickness.
2. Rubberseal Liquid Rubber Waterproofing and Protective Coating
Ponding water can easily ruin your roofing system, but not if your flat roof coating is the Rubberseal liquid rubber coating. This solvent-based liquid rubber product is impervious to ponding water, making it an excellent solution for your flat roof.
It also possesses high reflectivity, ensuring that your roof stays cool and protected all summer long. You will also have the freedom to choose the coating color that suits your aesthetic taste as the product comes in various colors; black, white, and grey.
You will love that it’s moisture and UV rays resistant. ‘But all products indicate that and don’t live up to their promises.’ Well, you are justified to think this way. After all, the market is laden with fakes.
This product is EPA energy star rated, so you can rest assured it’s UV rays resistant, guaranteeing long roof life. It’s also quite budget-friendly considering all the advantages that it brings forth.
If you are wondering why I haven’t discussed its ease of application yet, it’s because it falls on the cons this time. This product is solvent-based and thick, so you may find it harder to apply than your regular water-based product. But, this also has its upside. You want a thick coat to make your roof waterproof as a homeowner. And this product’s thickness provides that.
Pros
- Offers excellent protection against ponding water
- High reflective power
- Durable
- Flexible
- Budget-friendly
Cons
- Thick making it hard to apply
3. Ziollo RV Flex Repair 100% Silicone RV Roof Sealant
This coating takes the crown as the best silicone coating in this review. Its excellent adhesion is the perfect secret for restoring your roof after it suffers any damage.
Its 100 percent silicone makes it highly resistant to UV light and ensures that it can tolerate hot and cold temperature cycles very well. So, you don’t have to worry about whether it has excellent resistance capabilities.
The product’s resilience is also proof that it’s quite durable. The manufacturer is quite confident about its durability that the product has a lifetime warranty. And who wouldn’t love a product with a lifetime warranty?
If you are worried about its heat absorption and ability to reflect light, don’t fret. This product is highly reflective, helping to keep your home cooler even during summer and saving some of your utility bills. You will also love that it’s an Eco-friendly product made from nonhazardous material.
You may dislike its thickness, making it hard to apply on your flat roof. When applying it, start with a silicone base coat and then add another silicone layer. It will also take some time to dry up and is slightly more expensive than other products, although this is understandable as it is 100 percent silicone.
Pros
- Weather-resistant
- Highly reflective
- Durable and has a lifetime warranty
- Eco-friendly
Cons
- Too thick, making it challenging to apply
- Slightly expensive
4. L R Liquid Rubber Waterproof Sealant
Are you looking for highly flexible, waterproof, yet affordable flat roof coatings? If you are, then the L R Liquid Rubber Waterproof Sealant was designed with you in mind.
This product is highly flexible, owing to its over 1000% elongation capabilities. So, you don’t have to worry about minor movement on your flat roof coating destroying all your hard work.
Since its water-based, it will also be quite easy to apply. You can pour out the product for your flat roof and spread it on the roof with a squeegee or a broom. Ensure that you follow the manufacturer’s instructions on the number of coats you need to apply for a flat roof.
It’s also a UV stable product ensuring that your roof remains protected from the scorching sun, especially during summer. You will also love that the product is made without any solvents making it an environmentally friendly flat roof coating.
And the best part? It’s quite the durable coating owed to its weather and UV resistance. Neither the sun nor the snowstorms will be able to destroy this polymer-made coating easily.
The only disadvantage is that this particular product is only available in black. This limits its solar reflectivity. So you might not save much on your summer energy bills as you’d like with a highly reflective sealant.
Pros
- Water-based making it easy to apply
- UV stable
- Durable and highly flexible
- Environmental friendly
Cons
- Only available in black, limiting solar reflectivity.
5. Flex Seal Liquid Rubber in a Can
Getting a product that is UV and water-resistant may be easy. But what about a product that has these two features but it’s still mildew resistant?
Well, it may not be a walk in the park. Luckily, I’ve gone the extra mile to find you the Flex Seal Liquid Rubber, which offers these benefits and so much more.
With this product, you won’t have to worry about mildew infesting your flat roof coating as it’s mildew resistant. In addition, its UV and water-resistant capabilities ensure that it’s resilient enough to protect your roof from extreme cold or warm weather.
You will also love that it’s extremely easy to apply the product as it is liquid-based. I know how frustrating it can be to wait for flat roof coatings to dry. But, this product saves you the hassle of waiting and worrying that the rain will fall before drying as it has a relatively faster drying rate than other roof coats.
The fact that it’s available in white, black, and gray gives you, the buyer, the autonomy to select what you want. If you prefer flat roof coatings with high reflectivity, you can get white flat roof coatings. And the most favorite part? It’s a durable product. No one loves going back shopping after a short while, and this product will make sure of it.
However, I have to warn you that this product may have an excessive odor while drying, which can be quite annoying.
Pros
- UV, mildew, water, and chemical resistant
- Easy to apply
- Durable product
- Available in white, black, and gray
Cons
- May have an irritating odor when drying
6. Sashco – 14004-2 Through The Roof Sealant
Most times, you notice a roof leak when it starts raining. Then you remember, you can’t apply flat roof coatings under wet conditions-you at risk of having it all washed away. But what if I told you the Sashco Through the Roof Sealant can come to your rescue during such moments? Relieving, right?
Like its name, you can apply this solvent-based product through the roof in the rain and during a leak. It will stick and provide your home with the best production. And a reminder, it works great too on dry surfaces.
If you are big on aesthetics as I am, you will love this product as it can be painted over. So, you don’t need to stay with the original ‘boring’ or faded coat.
The product’s thickness will also save you the hassle of applying two coats or more for it to be effective. You will also love that it’s quite a durable product leaving you no space to worry about replacing the coat in only a few months.
However, the main downside is that it only comes in one-gallon containers. If you have a larger flat roof, this may be tricky as you must purchase several containers.
Its thickness may also be a pain point, although you get to apply fewer coats. You may find the product quite difficult due to the high viscosity. It may also take longer to dry again due to its highly viscous nature.
Pros
- Works great on both dry and wet surfaces
- Can be painted over
- Durable
- Thick
Cons
- Only comes in one-gallon containers
- Solvent-based and thick
7. Henry HE587372 Roof Coating
If you are looking for the best elastomeric coating for your flat roof, then the Henry HE587372 Roof Coating is the best today. It has a high solar reflectivity, reducing your home’s chances of turning into an oven during summer.
And you get to save some energy bills as its reflectivity makes it energy efficient. This product will also enjoy superior longevity as it is made from durable and resilient materials.
You will also love that it’s an economical product. One gallon of the product covers 100 square feet of your flat roof. Since this is a 5-gallon container, it can cover up to 500 square flat roofs or coat your 100 square feet flat roof 4 or 5 times.
Thanks to its air circulation technology, it’s also a moisture-resistant product that facilitates water evaporation nine times faster. This ensures that ponding water will not stay on a flat roof and cause mold, bacteria, and roof damage.
The product is quite thick, making applying on a flat roof under extreme temperatures and drying a bit challenging. So, if you are in a hurry to apply flat roof coating, you may find it annoying to go through these hurdles.
Pros
- High solar reflectivity
- Superior longevity
- Economical
- Moisture resistant
Cons
- Thick
Why do I Need Roof Coating for Flat Roofs?
If looking for a quick answer- yes, you need roof coating for a flat roof. But why?
Roof coating protects you and your home from irritating roof leaks. Coatings create a thick membrane that seals the small cracks, dents, or gaps on your roof. So, you have a durable roof and don’t have to worry about repair costs.
With roof coatings, you will also enjoy reduced energy bills. The coatings bounce the solar radiation away, reducing the temperatures of your house and consequently the cooling costs.
Elastomeric vs. Silicone Roof Coating
I often find myself in the middle of this familiar topic of discussion. If you are looking for a quick answer-, you should choose silicone coatings over elastomeric roof coating for flat roofs. But if the details excite you, read on to find out why.
First, what’s an elastomeric roof coating? It’s a fluid-based coating applied through spraying or back-rolling directly onto the roof. On the other hand, a silicone roof coating is a single layer of silicone rolled or sprayed as a liquid for filling in cracks, blisters, and seams.
One of the main challenges of a flat roof is ponding water, which negatively influences the lifespan of your roof. So, when looking for a roof coating, it should protect your roof from ponding water which the silicone roof coating achieves excellently.
How? Silicone is naturally non-water-based, allowing it to protect your roof against moisture penetration. You should also get a silicone roof coating due to its UV stability, allowing it to reflect 90 percent of the sun’s rays and saving you cooling costs.
Another benefit is its ability to withstand extreme temperatures and weather conditions, making it a better option to protect your structure. Due to its high solid concentrate, a silicon coating will require less material and labor for application. And who doesn’t like saving an extra coin and some time?
But, you need to be aware of the slip and fall risk that comes with silicone on your flat roof. You will need to include a walkway on your roof or be extremely careful when accessing the roof with silicone coatings.
On the other hand, an elastomeric roof coating may not be able to handle ponding water on flat roofs gracefully. Due to their liquid base, they can become brittle, lose mil thickness and delaminate from the roof on exposure to ponding water. They are better on steep-sloped metal roofs. However, they are also cost-effective, UV rays resistant, and easy to work with.
So, both silicon and elastomeric are viable options, but if your budget allows it, I recommend getting silicone roof coatings for your flat roof.
How do I Select a good Roof Coating for Flat Roofs
There are myriads of products available in the market. So, how do you select a good roof coating? Consider these factors to select the best roof coating for your roofing system.
1. Purpose of Roof Coating
“Will I use roof coatings for protecting or repairing my roof?” If you are shopping for roof coatings, this question should be on top of your list.
Some products will work best as a protective measure or sealant against moisture and sun, while others will work best for repairing your roof.
When considering the purpose of the product, you will also need to consider the roof types and roofing materials. Although some roof sealants will work well with any roofing material, most manufacturers will formulate the products effectively with specific roofing materials.
2. Type of Coating
Roof coatings can be solvent or water-based and further divided into;
Acrylic Roof Coatings
Acrylic coatings are the most popular roof coatings in areas that experience massive sunroof damage. These coatings are made from materials with high solid emulsion making them durable and highly reflective.
Traditionally, acrylic coatings were mostly used on metal roof surfaces. Still, today, they can be used for other commercial roofing substrates such as modified bitumen, built-up roofs, single ply, and spray urethane foam.
However, these coatings will not hold up well against ponding water, so they are not considered ideal for your flat roof but are an excellent option for sloped roofs
Silicone Coatings
Manufactured with high solids dispersion of 100 percent silicon, these coatings bear excellent surface adhesion and have high water resistance. They are popular in the market due to their ability to withstand ponding water.
Polyurethane Coatings
Polyurethane coatings are appropriate for areas with more rain and snow, as they are not very resilient against UV rays. You can find either aliphatic urethane coatings (usually used as topcoats) or aromatic urethane, a better option for use as a base coat.
Rubber
Rubber coatings are made of liquid rubber, an excellent guard against rain and sun for flat roofs.
You need to select the type that would work best for your roof type and is within your budget. Generally, water-based coatings such as Heng’s Rubber Roof Coating – 1 Gallon are budget-friendly, easier to apply have fewer odors, but they lack the weather resilience of solvent-based coatings.
Solvent-based are harder to apply, more expensive, and resilient against destructive elements. You can decide which coatings suit your priorities and select the best for your roof based on these characteristics.
3. Ease of Application and Thickness of the Coating
You should also consider the ease of application and thickness before purchase. This will determine the drying time and the number of coats you may need to apply for the sealant to be effective.
If the coatings are solvent-based, they will be thicker and harder to apply. It will also take a longer time to dry. However, if you are working in hot weather, these sealants will be the best.
It will be easier to apply water-based sealants such as acrylic roof coatings, and they may take shorter drying times. But, you may have to apply multiple coats for the product to be effective for your flat roof.
You may also hate working with thinner sealants in hot weather as they will be too runny and frustrate you as you try to achieve thicker coatings.
4. Reflective Power of Coating
When selecting the best roof coating for flat roofs, you also need to consider its reflectivity, which refers to your roof’s ability to reflect light.
The higher the reflectivity of the coatings, the cooler your home will be, especially during summer. You will be able to enjoy a cool home while still saving on summer cooling energy bills.
A common question I often get here is; how will I know the reflectivity rate of the coatings? Some manufacturers will indicate the amount of UV rays that their products can deflect. In the absence of such a label, look out for white and light-colored coatings as they have the highest reflectivity rates.
5. Coating Durability
How fulfilling would it be to purchase an incredibly durable roof coating? You would save a lot on repair and roof replacement costs. So I bet it would be 100% fulfilling.
When selecting roof coating for your roofing system, you need to consider durability. A good product like silicon-based Ziollo RV Flex Repair 1 may extend the lifespan of your roof by more than 15 years.
During selection, carefully consider the product’s warranty (how long it will extend the roof’s life). You should also consider how often to reapply the coating for best results.
Tips for Applying Roof Sealant
If you are a DIY person, I have prepared some tips for you to apply roof sealant for flat roofs in the best way possible. Let’s dive in.
- You need to select the right coating depending on your priorities and roofing needs. Do you want the sealant for repair or protection? What’s your budget and type of roof? These questions help you buy products that will suit your needs.
- Remove all debris collected on the roof to ensure that the product you apply will adhere to the surface.
- Look for any cracks or holes on the roof and repair them to ensure you leave only fewer weaker spots.
- Pick up your tools-rollers and brushes, and apply the product to your roof. If using a thinner product such as the L R Liquid Rubber Waterproof Sealant, ensure that you apply another layer(s) on top of the first coat to achieve the thickness you desire.
Pro-Tip: Always check the weather when applying to ensure it won’t rain. While most coatings are labeled water-resilient, the rain may wash off or render your coating useless if it falls before it’s completely dried.
Flat Roof Coating FAQs
What is the Best Product to Seal a Flat Roof?
The best product to seal a flat roof would be a silicone-based product. We all know how ponding water may threaten your roof life. Silicone roof coats are naturally non-water-based, allowing them to protect your roof against moisture penetration from ponding water on a flat roof.
What is the Longest-Lasting Roof Coating?
The longest-lasting roof coating is a silicone-based coating such as the Ziollo RV Flex Repair 1. The manufacturers offer a warranty of up to 15 years, guaranteeing you have quality protection. However, you need to conduct proper annual maintenance and inspection of the roof coatings after extreme weather conditions for it to serve you that long.
Do Roof Coatings Work for a Flat Roof?
Yes, roof coatings work for flat roofs. They seal any pesky roof leaks that appear on your roof. Typically, coatings create a thick membrane on your roof, sealing any cracks or dents. The coating will also protect other roof components from damage resulting from extreme weather conditions.
How Often should a Flat Roof be Recoated?
You should recoat your flat roof every two to four years, depending on the type of coating. Roof coating adds that extra protective layer to a flat roof extending its lifespan significantly. Coating your roof every five years will increase the lifespan significantly and protect your home from roof leaks while sparing you costly repairs.
How Long will Roof Coating Last on a Flat Roof?
How long roof coatings last on flat roofs depends on your coating. However, most roof coatings will have warranties between 5-15 years. A silicone roof coating is the longest-lasting, expected to last on a flat roof for 15 years. Elastomeric roof coatings last between 10-12 years.
Conclusion
You have everything you need to know about the best roof coating for flat roofs. Of course, you should always consider your budget and remember that not all quality products have to be expensive. You can get a great, budget-friendly product such as the Rubberseal liquid rubber coating.
But if you are looking for the cream, go with the crown holder for the best overall flat roofs coating, the Heng’s Rubber Roof Coating – 1 Gallon. Its versatility, durability, ease of application, and high reflective capabilities make it a coveted and quality product.
I hope this review has been insightful. Be sure to leave any comments and queries below.