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How to Waterproof a Shed Roof

For many of us, our shed takes pride of place in our garden, and we spend many hours tinkering with gadgets and fixing tools in it. For some, it’s a home away from home; if we want a bit of undisturbed time, we head down to the garden shed and enjoy a little peace and quiet.

If the shed is damp, smells of mould and its roof leaks, it won’t be a pleasant place to be in. More importantly, it is somewhere that we store expensive equipment that can easily be damaged by water — like lawnmowers, strimmers, and other power tools. If they get damaged, they can be costly and inconvenient to replace.

As with most garden buildings, water is the nemesis of sheds, and the one place that is certain to get wet when it rains is the roof! While it is important to make sure that other parts of the shed don’t leak or attract moisture, your top priority should be the shed roof covering. The best shed roofing is an investment that will not only prevent leaks but will also protect against bad weather and other environmental elements, such as sun and snow.

Rubber Roofing Direct’s shed roof kits have everything you need to waterproof or replace an under performing shed roof, including a high performance EPDM rubber roof membrane and adhesive. Order your EPDM shed kit online today for free 2–3 day mainland UK shipping on £300+ orders.

How to Check if Your Garden Shed Is Leaking

Before you waterproof your shed roof, you should check for leaks and find out where they are coming from. It might not only be the roof that is the problem, as leaks can also come from the walls, windows and doors. Furthermore, it could be a different issue altogether, such as condensation.

Water ingress from leaks and condensation creates the perfect breeding ground for rust, corrosion and rot, so this is the first and, arguably, most important part of the process when waterproofing a shed.

When to Check for Leaks

The logical time to check for leaks is as soon as possible after it has rained. If you leave it too long, the water might evaporate or dry up and not give you the right clues as to where it is coming from. Look for areas of damp, discoloured wood, puddles, or drips coming from the shed walls, ceiling, doors and windows.

What to Look for

You can also perform a thorough check for damage. Is it wood that has rotted? Is the water seeping up through the walls or the shed floor? Or is it coming from the roof?

Once you are sure of the source of the leak, you can get on with repairing or replacing it. If it is the roof that needs waterproofing, you need to find the best type of covering for your needs.

Need advice on how to seal a shed roof or have questions about our products? Contact our team of roofing experts at info@rubberroofingdirect.co.uk or on 01306 776626 and we’ll be happy to assist!

Choosing the Best Type of Roofing Material to Waterproof Your Shed

When choosing a shed roof, water resistance should certainly be at the top of your list of considerations — but there are other factors to consider as well. You should consider the cost and how affordable it is; the durability and resilience of the material; how easy it is to install; and the longevity of the product. If you are particularly proud of your garden, you might want your roofing choice to be good to look at as well.

Here are some of the most popular shed roofing options you can choose from when deciding on how to weatherproof a shed:


EPDM, which also goes by the less catchy name of ethylene propylene diene terpolymer, is at the top of our list because it ticks all the right boxes. It is a cost-effective, durable, long-lasting and easy to install flat roof membrane. It’s also totally waterproof! When purchased, it comes in one large sheet, which has been homogeneously factory vulcanised to prevent water from being able to seep through or allow ingress to occur. It is also eco-friendly and offers UV protection against the sun’s rays. We will dig a little deeper into the benefits of this rubber roofing material shortly, but let’s look at some other options first.


Felt is the least popular waterproof shed roof option. Traditional roof felt is the cheapest way to waterproof a shed roof, but its benefits end with its low cost. Felt is one of the least durable shed roofing materials and can’t be expected to last anywhere near the length of time that EPDM will. You can expect your roofing felt to last 5-15 years depending on the quality of the mineral roof felt you buy. It is sold by weight from 15 lb to 90 lb — the higher the number, the thicker it is.


Metal shed roofing sheets are a reasonably good option that will make sure that your shed stays waterproof. Metal roofing is available as corrugated sheets or a box profile. As an aesthetic choice, popularity is divided — some like the modern look of metal; others not so much. Depending on the environment it is installed in, it can last up to 25 years. However, it’s not a good choice for coastal regions where salt in the air could cause the metal to corrode. Installation is relatively straightforward, but you must make sure it is regularly painted to protect it from rusting.


Wood shingles can be made from several types of wood, such as redwood, cedar and oak, with the latter being the most expensive. If you want to give your garden shed a natural look, wood shingles are a great option, and they are durable enough to last up to 30 years. It’s one of the more costly options, but it is a great waterproof shed roof option and looks great as well.

Want to know more about how to waterproof your shed with rubber roofing or why an EPDM membrane is the best waterproof roof for a shed? Keep reading or contact Rubber Roofing Direct today.

Why EPDM Is the Best Waterproof Solution for Your Shed

While all the options above have their pros and cons, EPDM is the most cost-effective waterproof shed roofing available. Once installed, it could even outlast the lifespan of your shed, as this type of rubber roofing has been known to last 50 years or more. It’s also affordable to purchase, easy to install as it comes in one piece, and requires little upkeep.

Read more about the waterproof properties of EPDM and why installing an EPDM rubber roofing system is the best way to waterproof a shed roof.

Other Considerations When Waterproofing a Shed Roof

Though the roof of your shed is the main surface that you should waterproof, neglecting other areas could still result in your shed becoming damp, musty and mouldy. Here are some other factors to think about to keep the inside of your shed cosy and dry.


Shed walls can suffer from similar issues to a roof, especially if they are in an exposed position in your garden. On windy days, rain constantly battering at the side of your shed can cause it to leak. Even if your shed is built in a less exposed area, wear and tear would eventually result in cracks and splits. While your EPDM rubber roofing might last 50 years, if not taken care of, it is more likely the walls will be the downfall of your shed; not the roof.

There are several options to waterproof the walls of your shed. These include using timber (wood) treatments and filling any cracks and gaps you come across with caulking.


If you want to kill two birds with one stone — give your shed a little colour and make it more water-resistant — then choose waterproof paint. It makes your shed walls more resilient in a similar way to a timber treatment. Once you’ve given your shed a fresh new look with waterproof paint, it won’t need painting again for a few years at least.


Remember not to neglect the walls, windows and door of your garden shed to ensure that it is totally waterproof. And if you have expensive power tools and gardening gear in your shed, it’s best that you don’t leave it too late.

As with the doors and windows of your home, these are common areas where rain can enter if there are small gaps. This is why sealing a shed roof is so important. You can use silicone-based caulk or sealant to fill the gaps and then apply foam weatherstripping around the doors and windows to create a further seal.


If you are installing a new shed from scratch, you are in an enviable position because you can choose the best place to locate it. It would be best if you avoided areas in your garden where water might tend to pool. Rather aim for a level surface that is not low lying. Install it in an area that gets the most sun as direct sunlight will help evaporate any moisture build up on your shed after it rains, which lessens the chances of it staying wet for too long.

When you build your shed, make sure it is up off the ground on a solid surface with an appropriate shed base underneath it. By doing this, your shed won’t absorb moisture from the ground. You can choose from several shed bases, such as a gravel or concrete base, to provide a reliable foundation underneath your shed. Combined with a long-lasting waterproof roof such as an EPDM rubber membrane and a little bit of regular maintenance, your new shed roof and building should remain moisture-free and be able to stand the test of time.

Browse our range of EPDM membranes online or get in touch with the Rubber Roofing Direct team if you need more advice on waterproofing for a shed roof from a rubber roof specialist.

How to Install EPDM

The great thing about EPDM is once it’s installed, it is not likely that you will ever have to do the job again. For instance, if you are currently in your 30s, you can expect your newly installed waterproof shed roofing to still be going strong into your 80s. And if it does need replacing, it will be a job for the grandchildren!


Measure your shed roof precisely before purchasing your shed roof kit. The kit will include an EPDM rubber roof membrane, EPDM adhesive, gloves and a roller. You’ll also need scissors, a hammer, and galvanised clout nails.


Clean the roof, remove any nails, and ensure it is dry. Unwrap the EPDM rubber membrane and place it unfolded on the top of your shed. Give it about half an hour to relax.


Apply the included EPDM adhesive with the roller evenly over the roof surface. Then roll out the EPDM membrane using a soft broom to ensure that there are no air bubbles or creases.


Trim the membrane to size, removing the excess with sharp scissors and leaving around 50 mm overhang.


Fold the rubber membrane back on itself and fix it in place with the galvanised nails.

For a more detailed guide on how to waterproof a shed roof using an EPDM rubber roof membrane, see the full instructions.

How to Install Roof Felt

If you have decided to go with the cheaper option of waterproof roofing felt, then do note that it will not be as durable or long-lasting as other materials. Still, putting felt on a shed roof is relatively easy, so once you’ve carried out the task, the next time will be easy as well.


For a typical A-frame, measure the length and width of one side of the shed roof and multiply by two for the total area. Purchase your roof felt to match the dimensions of your roof.


Using a scraper on a long pole, remove any existing felt or shingles from the shed roof. Clean the roof and remove or drive any nails that are sticking out below the surface.


Even though you are waterproofing a shed roof with felt, it is a good idea to add a layer of weatherproof paint to add extra protection. You can always use this time to coat the walls of your shed with waterproof shed paint as well.


Unroll the felt and, using 20mm long galvanised nails, pound one nail every 30cm around the perimeter of the first piece of felt. Slightly overlap the first piece with the second one and follow the same instructions nailing it to the roof. The number of pieces of felt used will depend on the size of your shed roof.


Once the felt is nailed down on either side, centre the last piece over the apex overlapping both sides of the roof and you’re finished.

Get in touch with the Rubber Roofing Direct team if you have more questions about how to waterproof a shed roof with EPDM membranes.

Rubber Roofing Direct — Shed Roof Waterproofing Experts in the UK

With over 20 years of experience in the roofing industry, Rubber Roofing Direct is a rubber roofing specialist trusted by both trade roofers and DIYers in the United Kingdom.

If you want to waterproof a shed, it doesn’t have to be a daunting project — a new EPDM shed waterproof membrane from us can be installed in a weekend and can last over 50 years! That means that once you waterproof your garden shed this way, it’s likely you’ll never have to do it again.

We also stock shed waterproofing products such as drainage outlets and EPDM sealants to ensure your waterproof shed roof covering lasts.

Now that you know how to waterproof a shed roof, it’s time to get started — Browse our range of EPDM shed membranes online for a rubber roof that will keep your shed sealed and dry!