When choosing a new roof, don’t forget to consider what surface the roof will nailed onto. I recommend that all roofdecks, especially in moist climates like Seattle, are CDX plywood and not OSB.

What’s a roofdeck? The roof deck is the surface underneath your roof and roofing underlayment. It is usually made of 4′ by 8′ sheets that should be 1/2″ thick.

What is CDX? CDX is veneer plywood. It is made of multiple layers of thinly cut, solid sheets of wood that are pressed together.

What is OSB? OSB is a cheap imitation of CDX. It is made of wood chips and glue.

How do CDX and OSB differ in performance? OSB does not do well when it gets wet. When OSB comes into contact with moisture, it swells and soaks up water. Then it can grow mold or simply just fall apart. It works fine for interior walls but I don’t recommend it as a roof deck at all. Many home builders construct houses with OSB for the entire roofdeck or sometimes they use CDX around the perimeter edges and OSB in the center. As a roofing contractor in Seattle, I strongly recommend that OSB is never used as a roofdeck. Always use CDX.

What if my house currently has an OSB roofdeck? Consider having the OSB replaced with CDX when your roof is replaced.

Below is a close up of OSB:

Below is a close up of CDX:

When replacing your roof it is very important to replace all metal flashings. Many roofing companies in Seattle will replace your roof shingles but leave the old metal flashings behind. This causes two problems: First, the roof is leak prone in the areas with old roof flashings. You may have a new roof, but your metal flashings are old. Second, old flashings are unsightly and will detract from the finished look of the home.

One flashing that is commonly not replaced by Seattle roofing companies is roof to wall flashing, also called roof to wall metal.

Below is a photo of old roof to wall metal.

Below is a photo of newly replaced roof to wall metal.

If you want your new roof to last a long time without leaks, make sure valley metal is installed as part of your roof system. We see a lot of Seattle homes with leaky roofs because of this problem alone. The valley area of a roof is a very leak-prone if not installed correctly.

Many roofing contractors try saving a little money by leaving out a few key components and a lot of homeowners don’t know the difference. Valentine Roofing installs valley metal with every new roof installation. Below is a picture of the final product.

One thing you can’t see in this roof photo is that the valley metal extends two feet under the roofing on each side of the middle seam in the metal. Being a roofing contractor in Seattle requires a very high level roof installation as the weather can be very unforgiving. Ultimately, it does not pay to skimp on your new roof.

There are many components to installing a new roof that will last and won’t cause you problems down the road. One key component is installing gutter edge metal. By the way, this is also known as gutter edge flashing. A roof is supposed to get water off of your house and into the gutters without anything getting wet. If your roof doesn’t do this then you will have rot or mold somewhere on your home.

One big problem especially here in the Seattle area is water dripping behind the gutters and soaking the soffit or eave of a house. To prevent this, make sure your roofing contractor installs gutter edge metal under the felt paper (aka tar paper/underlayment). This should be 26 gauge steel with a baked on enamel coating that matches the color of the roofing being installed.

Here is an up-close of the gutter edge metal:

Here is the finished installation: (note how the bottom edge of the roofing lines up very straight and neat. This goes a long ways in getting a beautifully installed roof.)

This is one of many steps to make sure water doesn’t get somewhere it isn’t supposed to. There are a lot of precautions to take here in Seattle that in other parts of the country wouldn’t be a big deal.

On our homepage link below, we have a “5 Secrets” PDF which details four other important elements of installing your new roof along with the gutter edge metal.

There is a lot of emphasis given to picking the right roofing product but few realize the importance of picking a quality ridge cap. Most of the roofs we install are with CertainTeed brand roofing products. I like CertainTeed’s quality and look for their roofing shingles. But even a beautiful roofing installation using a CertainTeed product like Presidential, Presidential TL or Landmark TL doesn’t look complete without Mountain Ridge ridge cap.

When to roof planes meet at a peak, that is a ridge. Ridge cap is the roofing product that is installed on the ridge. Some ridge caps are flat looking, which works fine for a flatter looking roofing product but when you have a high-end roofing product, you need a high-end ridge cap. Mountain Ridge is just that. It has a thick, folded look that really accents a roof installation.

Here is an up close look at CertainTeed’s Mountain Ridge.

You can see on the photo above that there is a quality product installed that has some depth to it. If the ridge cap laid flat, it would really make for an underwhelming finished look. Instead, Mountain Ridge was used to highlight the roof.

Avoid knock off ridge cap productsthat aren’t made by the same manufacturer as the shingle. In other words: If you have a CertainTeed roof installed, make sure the ridgecap is also CertainTeed.

After all that goes into a new roof, make sure it is finished off right.

I am asked all the time “How long will my cedar shake roof last?” Here in the Seattle area, there are miles of neighborhoods built with cedar shake roofs. This is particularly true in Redmond, Sammamish and Issaquah on Seattle’s Eastside.

You can expect an original cedar roof to last 17-25 years. The reason I specify “original” roof is because home builders don’t use a premium grade, pressure-treated, 3/4″ cedar shake. If they did, then your roof would last 25-35 years.

whether or not your cedar roof lasts 17 years or 25 years will depend mostly on how steep your roof is. The steeper, the longer it lasts because the water runs off much quicker and the sun doesn’t beat down on it at a direct angle. The sun does the most damage to a cedar shake roof for sure as the South facing side is always worse off then any other side. Having your roof shaded in the afternoon and having a pitch of 8/12 or greater will go a long way in how long your roof lasts.

You can have your shake roof pressure washed and treated but I wouldn’t recommend doing this after it’s 18 years old as it can definitely do more damage than good. We get a lot of calls from those who just had their old shake roof pressure washed. Having the roof treated without being pressure washed is the best bet and even then you really should just stop with any type of maintenance after it gets towards 20 years of age.

Sure there are many companies who will take your money in exchange for “prolonging the life of your cedar roof” but most often it shortens the life. Bottom line: When your cedar shake roof gets 18 years plus in life, don’t hire anyone to maintain it. Just save your money for a new roof.

Here in the Seattle area, especially on the Eastside, there are many aging cedar shake roofs. We receive a lot of phone calls from homeowners with cedar roofs that are looking for an alternative. Many don’t care for the maintanence and short life span. If you find yourself in this situation, Here are a few options to consider:

1. Get a better cedar shake roof! I know this sounds crazy if you want anything but cedar shake, but a 3/4″ quality cedar shake that is pressure-treated will last much longer (10 years probably) than your current “builder-grade” non pressure treated 1/2″ cedar shake. You don’t even have to maintain it! So if you like the look of cedar there is no reason to have to completely go away from it.

2. A nice composition roof. Some composition or “composite” roofs look very flat and unflatering. I’ve seen some serious buyers remorse after changing a cedar roof that is thick and depth with a flat composition roof. Presidential and Presidential TL by CertainTeed are the most popular composition roofs for houses that were cedar. That’s because they are thick and somewhat shake looking and keep the overall cedar look. My favorite shake look is Landmark TL by Certainteed. This is not a very common product and most roofers won’t even bring it up in conversation but it looks very much like shake and Shenandoah and Resawn Shake are great colors. Here is online brochure.

http://www.certainteed.com/resources/RPG_Landmark-TL-West-Broch.pdf

3. Go for recycled synthetic shake. This is the most expensive option by far but if you want a roof that looks like cedar and lasts 30-40 years without growing moss or requiring maintanence, this is it. synthetic shakes are also very beautiful and can really set your home apart from you neighbors.