Torch Down for What?

Your guide to flat roofs in the Pacific Northwest

Roof maintenance in the Pacific Northwest is unlike any other market out there.

With average rainfall around 44 inches per year, Kitsap County in particular requires careful attention be paid to the roofs of commercial buildings. Unfortunately, many commercial buildings here still rely on so-called ‘flat roofs’, which are typically either ‘torch-down’ or ‘built-up’ products which are explained in more detail above.

The biggest problem with flat roofs is that if the slope is not designed properly, or it has too many penetrations (HVAC units, vents, etc.), water can sometimes not flow properly across the roof to the designated exit points (called ‘scuppers’). ‘Improperly flowing water can cause ‘ponding’ – the accumulation and settling of water that does not drain from the roof.

Here’s what you need to know to protect your investment from the relentless PNW rain.

Built Up Roofing (or BUR) describes the process of applying layers of various materials one on top of the other to ‘build-up’ a thick, waterproof roof with multiple redundancy. Advantages include superior water-proofing, better weather and wear protection, and generally lower maintenance costs over time. On the other hand, these types of roofs are much more expensive initially, they create noxious fumes during installation, and take longer to install. Not particularly well suited for re-roofing an occupied structure, where the installation time and fumes are of primary importance. But for new construction where the owner intends on holding the asset for an extended period of time, BUR is definitely the right choice.

Torch-down roofs are another very common type of flat roof, and it comes with its own set of pros and cons. On the plus side, they are much, much cheaper to install. With multiple layers of material built into a roll, one man can torch down an entire roof in a very short amount of time. When installed correctly, they can be a decent product, but unfortunately, many installers will cut corners or otherwise not take the time to make sure that each roll is properly adhered to the next.

The cons then being frequent failure at the ‘seams’, where each roll meets the next. Even one small little gap between the sheets can cause catastrophic failure of the roof, so it requires very careful application. Another drawback is the danger and potential liability arising from using an open flame on your roof. As you can see from the picture, it takes a very experienced roofer to get the right temperature of the material without burning it while simultaneously getting the roll to adhere 100 percent to the base. Much less expensive to install, but more prone to failure over time, this is a very common practice in developments where the goal is to spin off the asset shortly after construction.

All in all, there are countless types and sub-types of roofs for commercial buildings. Which one is right entirely depends on your budget, and the long-term plans for your asset. However, the most important component in preserving any roof is regular inspection and preventative maintenance once your roof is installed. With regular removal of leaves and pine needles, and a visual inspection for possible failure sites, a roof can live long past its warranty period which usually varies between 10 and 20 years.

When the time does come to replace your roof, consider the good and bad qualities of each respective roof type before deciding which route to take.

Investing a little bit of time now can save you thousands of dollars in the future!

Cameron Wilson is the director of brokerage services and business development at Bradley Scott.