How To Install Asphalt Shingle Leak Barrier In The Roof Valleys

Roof shingles are growing in popularity across Australia as a roofing material. Environmentally friendly, attractive, and perfectly capturing the style of classic American homes like Hamptons-style houses, there’s a lot to love.

When installing roof shingles on a roof, there are a few special considerations to make to get the most out of them.

Today we will address how to properly waterproof your shingled roof to prevent leaks, mould, and structural deterioration.

Preventing Roof Leaks

If you ask any good roofer what part of a roof is most prone to leaking, they’ll more than likely tell you it’s at “the valleys ” – the vee-shaped channels that run the length of a “fold” in the roof.

When it rains, and with the sheer volume of water flowing down these valleys, it makes them the most likely place for a leak to occur.

If the valleys are full of leaves, the leaves can create blockages that makes water pool, increasing the likelihood of a leak.

You can tell if a roof valley is leaking when you see staining on the ceiling indoors underneath where the valley is located. If left unchecked, this leak can seriously risk the stability and strength of your roof.

Suffice to say, extra care needs to be taken when waterproofing your roof valleys.

When installing roof shingles, a thick waterproof membrane is applied down every roof valley. This specially developed leak barrier acts as a water and ice shield, providing excellent waterproofing to these highly vulnerable areas.

Since it’s so important to properly waterproof these valleys, it’s vital that this leak barrier is installed correctly.

Let’s take a look at how they’re installed for the best results.

Installing GAF Stormgard

As with most things, preparation is key to success. We obviously know that roof valleys take a lot of water when it rains, so it’s essential to take your time in this area.

We’ll be using a leak barrier known as Stormgard, one of the best in the industry. Stormguard is one of the most highly developed leak barriers in the industry.

Developed by GAF using their advanced technology – the same manufacturers of America’s leading choice in roof shingles – it’s proven over time to provide outstanding leak protection.

It’s a film surfaced, fibreglass-mat reinforced leak barrier.

It has an adhesive backing making it easy to install, and the membrane is self-sealing around nails.

No matter how well made it is, however, it won’t do us much good if it’s not installed properly.

To begin, you want to have a flat working surface. While Stormgard is self-sealing around nails, it’s always best to have as flat a surface as possible to start with.

Have a hammer ready and scan the entire valley area for any nails that didn’t get driven all the way down. Use your hands to feel for any high nails, or run a level over the area to see if you can feel anything.

Hammer down any loose nails you happen to find and make sure they’re all perfectly flat.

Stormgard features an adhesive backing. Just before you’re ready to lay the Stormgard down, give the area a good sweep, or better still, use a mini blower to get rid of any dust or dirt. If you don’t, the adhesive side won’t adhere properly.

Then measure and cut a length a length of Stormgard to fit the valley. A good tip is to fold the Storm Gard in half lengthways to create a slight crease down the middle.

This will help you align it with the centre of the valley and give you the most amount of surface contact with the roof.

Where To Use Stormgard

In some colder climates it’s a good idea to put the Stormgard over the eaves and rakes as well.

In Australia it’s generally only needed in the valleys. People in colder parts of the country such as Victoria and Tasmania may consider using it on the eaves and rakes as well.

With the length of Stormgard folded over, remove the backing to expose the adhesive layer on one side.

Then gently stick the membrane down along one side of the valley. Press firmly to stick the barrier down, while making sure to avoid any bubbles particularly in the centre of the valley.

Smooth the Stormgard with something flat and rigid for best results.

Then fold the membrane over and repeat the process for the other side.

You can tack the membrane along the edges to ensure a more secure fit. Be careful not to nail too close to the centre of the valley, or you’ll ruin the effect of the membrane.

Stormgard actually has a red line down its length that serves as a guide. Please ensure you nail outside this red line.

And that’s it!

As you can see, installing a good waterproof barrier isn’t difficult. However, it should be a process done with care.

Take your time and don’t rush.

Bubbles under the Stormgard can lessen its effectiveness and spoil the waterproof quality of the membrane. Take the time to smooth down the membrane properly as you go, and make sure the nails are flattened before you even start.

Are you looking to design your next home with roof shingles? GAF is the leading supplier of roof shingles in the USA, and they produce Stormgard.

With GAF, you get all of the materials you need to design an authentic American-style home like the increasingly popular Hamptons style. While tile roofs are more quintessentially Australian, for that truly authentic Hamptons look – or just to separate yourself from the crowd – make sure to get GAF roof shingles.

You can read more articles on how to properly install roof shingles in our blog, or contact us today to arrange roof shingles for your next development project.