How to Waterproof a Shed

It’s important to waterproof a shed prolong its lifespan, as well as protecting the contents inside. If water gets in to your shed, it can create mould and mildew which can smell awful and cause irritation to your skin. The water can also rust your tools and equipment. Here we look at how to approach shed waterproofing.

Waterproof a shed

Get the right base

If you’re looking at how to weatherproof a shed, you should look first at getting the right base. If your shed sits directly on to the ground, then moisture can easily enter, making it damp.

A simple wooden base will keep your shed from directly touching the ground and will allow air to circulate which helps to prevent rot. If you have a larger, heavier shed, a concrete base is advisable.

Waterproof a shed by checking windows and doors

Wood naturally shrinks over time, and this can cause cracks in your windows and door frames allowing water to seep through. This can lead to rot and damage to your shed.

When waterproofing a garden shed, fill in cracks or gaps in your window and door frames with expanding foam. If you find signs of rot, you can dig it out with a screwdriver, fill in with a wood filler and then sand and paint to look as good as new. Remember to secure your shed door to keep water as well as intruders out.

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Clear out shed gutters

Waterproofing a shed roof involves regularly clearing out the gutters. If leaves and debris block your shed gutters, then pools of water can collect on the shed roof making it more susceptible to a leak. If you don’t have gutters, it’s worth considering installing some as they will help solve drainage problems.

How to waterproof a shed roof

Your shed roof is the most exposed to the rain and elements and therefore needs careful attention when looking at how to waterproof a shed. Regularly inspect the weak points on your roof such as the edges and ridge lines, as well as where the roofing material is nailed down.

Felt will deteriorate over time; patch it to repair worn out spots or, when the time comes to replace the entire material, you opt for a shed waterproof membrane for the ultimate in shed waterproofing.

Take a look at our guide to protecting your shed against the effects of climate change which includes information about how to waterproof a shed in extreme weather.

Waterproofing shed walls

You should regularly use a timber treatment on your shed which acts as an extra layer of protection. A timber treatment will prevent your shed from staying damp after a downpour.

Consider insulating your shed. This will protect it from getting damp by moderating the temperature inside and preventing condensation.

Finally – to waterproof garden sheds – don’t forget to ventilate! Airflow prevents the build-up of moisture which protects the longevity of your shed as well as its contents. Ventilate by opening the shed door and windows on milder days or by installing vents. Find out more about shed ventilation in our guide to preparing your shed for winter.

Looking at how to waterproof a shed? Let the professionals at Surrey Hills Garden Buildings show you how!

It’s essential to waterproof a shed to protect the building itself, as well as whatever you have stored inside.

Our handy tips will help with shed weatherproofing, but remember your job is made easier if you start with a quality built shed in the first place.

Visit our dedicated show site for inspiration, or please do get in touch with our helpful team, who will be happy to answer any questions that you have.

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