How to waterproof a roof

leaking roof

You might have experienced this problem recently. Imagine sitting in your living room with your loved ones and suddenly you feel a light drizzle forming on the top of your head.

What could it be?

You look up in amazement and you see that water is leaking from your roof! Can you imagine the annoyance and frustration when this happens! Dealing with a leaking roof is one of the most frustrating situations a homeowner can face on his property.

Finding a way to fix this problem is what we will discuss in this article, there are many different options so let’s find the best option for you.

Find the leak in your roof

leaking roof

First things first, where is the water coming from? Is it just one location or multiple? Also, is this the first time that you are having a leaking roof, or has it been a problem you had to deal with in the past?

If you have an attic it might be the best place to start your investigation. Climb up there with a flashlight and see if you can find the weak spot of your roofing structure. Look out for small pools of water that has gathered, that is a solid indication of leakage.

Now, if you have found a weak spot you have identified the affected area. Although, it’s not always that easy. If you haven’t found the cause you need to go outside and climb on top of your roof. We advise you not to climb on the roof if it is wet or if you’re hesitant. Be careful because you can always buy a new roof, but it is much harder to replace a broken limb.

When on the roof look for low spots in comparison to the rest of the surface. This often indicates that the water has found a gap to penetrate the structure. Also look out for shingles which are worn out. You can identify this by how smooth the individual shingles are. They should feel and look sturdy.

These methods help you identify the issue. A quick note on roofing problems. You don’t have to wait until your roof is leaking to know that you have an issue. Prevention is often much better that fixing the problem when it’s already in its final stages.

Wind is an easier indicator to identify if you have any issues with your roof, long before water can penetrate the surface. Go into your attic occasionally and try to identify if there are any areas where cold area enters your property. If you find such a place mark it and pay close attention to it. Even better instead of marking it, call a licensed roofer to have a look at the issue and consult with them what the next best step is in your situation.

What methods are used to waterproof a roof?

There are a few good methods out there, which you can do yourself or outsource to a roofer.

EPDM rubber

epdm rubber roll

The most common used material to stop leakage is EPDM rubber. This long slate of synthetic rubber laid underneath the shingles. Normally this is done on every roof job and the material is very durable. Although, some people either miss the whole rubber slate or it has not been applied right by the homebuilders. Wear and tear are rare on this material because of how durable it is.

Buying EPDM rubber should be easy because it is widely available. The price for EPDM slates range from £10 to £40. You can get a full kit DIY kit but that is slightly pricier. The DIY kit prices range from £300 to £450.

Roof paint

roof worker applying paint

Another material commonly used is roof paint. This material is made from Acrylic. Roof paint is better for covering small and contained breaks in structure. The only downside of roof paint is that it is best used on flat roofs. The paint is not as effective on pitched roofs, unless you apply it underneath the EPDM rubber or shingles. Roof paint is still applied to all types of roofs, but it is most effective on flat roofs.

With roof paint quality really matters, the paint you use can have a drastic impact on how long your roof will last. There have been many horror stories of poor workmanship, over promised and under delivered situations in the past causing clients to shy away from this option but roof paint can waterproof your roof and make it look nice at the same time.

In this article we can’t recommend a specific brand of roof paint because we haven’t split tested them yet, but we will soon. If you’re unsure on which brand to choose, give us a call and we can share our experience.

The price range for roof paint varies from low market cheap options such as silicone roof paint, for 5kg you should pay about 25 pounds. For quality roof paint the price ranges between 60 to 80 pounds for 5kg. Depending on how big your roof is, you might need a few of these buckets.

When to do it yourself

Having met people who took the faith of their property in their own hands and decided to repair their roof themselves, I’ve noticed that it is best to leave it to the experts.

Although, there are a few instances that you can do it yourself and be successful at it. The first type of people I see that don’t need a roofer are people who have worked in construction and are experienced in fixing stuff around the house. The so-called handyman – doesn’t have to be roofer by trade but knows enough about repairing stuff that he can do it himself.

The second type of successful roofing repairs are people who tackle small issues. Having a leak that you can fix with a readjustment of a shingle, do it. These types of jobs can be done by all, but you must be careful.

Make sure you got insurance in case it goes wrong because an accident sits in a small corner.

When to hire a professional to do it for you

happy roof worker

There are a few reasons to hire a roofer. Firstly, if you have no experience in repairing a roof, or if you don’t have the time to repair the roof or if you simply must fix the problem as soon as possible.

Hiring a roofer can help you avoid a lot of unnecessary headaches and worries. Professional roofers have a structure and the needed material to get the job done. You will be amazed at how easy it is for us compared to how hard it would be for you to fix.

Having identified the problem as we’ve described earlier is just the tip of the iceberg. A full examination of your roof will show what needs to be done to clear current errors and prevent future problems.

For the regular homeowner it is difficult to identify mold or damp which builds up in your roof. This might not cause direct leakage or other direct signs of a weak roof, but it will affect your health without you even knowing what is going on.

If you have tried to fix your roof on your own and it did not work out as you were hoping you can also contact us, we can help you finish the job you’ve started.

Waterproofing a flat roof

a flat roof

Are you experiencing leakage from a flat roof? Or are you trying to prevent a leakage from happening. Either way, this article will answer all your waterproofing questions regarding flat roofs.

Flat roofs are common among the whole world. Builders have been constructing these types of roofs since ancient times. It is slightly easier to construct than sloped roofs and it often looks better. Currently flat roofs are mostly used on commercial buildings, like office blocks, malls and high rises.

Although, flat roofs are common all over the world the material used differs a lot. In colder climates a material such as asphalt is used. In warmer climates concrete is used for roofing.

Which material is best for Waterproofing a flat roof?

There are many options of material to fight the elements of nature. Some better than others. Let’s discuss them so you can make an informed decision when you need to. Following is a snapshot of all the material you can use for constructing your flat roof in western climates. I will briefly discuss the pro’s and cons of them.

  • Asphalt
  • EPDM (Ethylene propylene diene monomer rubber)
  • Turbo seal
  • CSPE (Chlorosulfonated polyethylene)
  • Modified bitumen
  • Cold applied liquid membranes
  • PVC (Polyvinyl chloride)
  • Flexible thermopolyolefin
  • Green roofs


asphalt shingles

Asphalt comes from the oil industry; it is a disposal by product of refineries. There is a difference in quality of asphalt. Some asphalt is made with the main purpose to be used on roofs; the quality of this asphalt is much higher than the previously mentioned one.
Leaks are caused by deterioration of asphalt. The higher quality ones have a longer life expectancy. Extreme weather conditions can reduce the time of use. To combat this, experts recommended to sprinkle gravel on asphalt roofs, this will slower the degradation of the roof. The correct installation can make your roof waterproof. Do it right the first time because installing or repairing an asphalt roof is labour intensive.


epdm rubber roll

EPDM Is an abbreviation for a synthetic rubber type used on flat roofs. When installed correctly the life span of the roof can be as high as 50 years! There are three ways of installing EPDM.

First the mechanically attached, in this method roof membranes are secured with long nails into the roof.

Secondly, Ballasted roofing. Ballasted means that the EPDM layer is hold in place by large stones and slabs. So, the EPDM layer is laid underneath the layer of stones.

Thirdly, the fully adhered method is the longest lasting EPDM installation. It simply means that the EPDM layer is glued to the roofing surface. Wen done right the roof will be wind resistant, sun resistance and other extreme weather conditions.
This is great material for waterproofing, water can’t penetrate it easily because it is rubber.

Turbo seal
This sounds like a weapon from a comic book, but it is a real-life roofing material, widely used by experts in roofing. Turbo seal is a self-healing membrane made of recycled material. Not great for waterproofing roofs.

More commonly known as Hypalon. This material is used on roofs because it is very resistant to extreme heat and cold. In some parts of the world this material is not available anymore because research proves that it can be damaging for the public health. Although, it is very water resistant.

Modified bitumen

roofer melting felt onto roof

This material is a modification on the asphalt mentioned earlier in this article. In the late 90’s property developers noticed that the standard of asphalt will increase by adding coal tar pitch to the asphalt. The two types of material used to modify the asphalt is called SBS and APP.

The application of APP caused a fire hazard to residents and is not a common use anymore. SBS on the other hand is much like rubber. It increases the durability and flexibility of asphalt.

Altogether, modified bitumen is rarely used anymore, we recommend you avoid it because it does not help with waterproofing your roof and the installations is difficult.

Cold applied liquid membranes

applied liquid membranes on roof

Also know as liquid roofing. The plus side of this type of flat roofing method is that the application does not cause a fire hazard. In Britain this is the most used material for flat roofing and we highly recommend it because of safety and the amount of experienced construction workers you can find for this material.

PVC membrane roofing

Roofer applying PVC

PVC roofs stand out on flat roofs because they are white. Not many roofs are white but the colour of this material aids in energy efficiency. The surface of a PVC roof (vinyl roof) will not drastically increase in temperature when exposed to harsh sunlight. Matter of fact, it only increases in a few degrees, whereas normal roofs can become 10x hotter than their normal state. This will reduce the need for air conditioning, which in turn reduces your energy bill.

Only caveat of Vinyl roofing is that it can be more costly because of the material it is made from – fossil fuels and salt. For waterproofing your roof this material is great.

Green roofs

house with green-eco roof

Green roofs tie in nicely with the PVC roofs because they both reduce your energy bill. You have probably guessed it; green roofs are roofs with patches of grass on them. My favourite type of roofs. On a flat roof this can be easily done.

First you apply a thick layer of dirt, on top of that you start laying patches of grass or other types of plants. Rain will be absorbed by the dirt and will be used for plants; sunlight will be used by the plants to grow.

You will have a heat and water absorption system on your roof, just like PVC roofing this will decrease the energy kwh used on your energy bill. Also, in the winter your roof will help insulate the heat produced in your house.

A few other but important benefits is that a green roof will create sound insulation in case you want to throw a party but not wake up your whole neighbourhood. Finally, green roofs are eco-friendly and help the overall environment.

Green roofs are great for waterproofing your roof and have extra benefits for you.


We explored a few different materials to waterproof your roof in this article. Some are better than others due to price, frequency of use per region and how water resistance the roof is. There are more lesser known materials out there which we haven’t discussed in this article but for more detailed and tailed explanation I would advise you to speak with an expert.
We haven’t covered Glass-reinforced plastic, Metal flat roofing because they do not do well in waterproofing flat roofs. They are great in other situations but from experience we do not recommend them on flat roofs.

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