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Detecting Rot & Preventing High Prices

TLDR : The Main Takeaways If You Don’t Have Time to Read The Entire Article

  1. Homes built 10 or more years ago generally use OSB and/or Wood Trim — these materials act like a sponge soaking up water and rotting over time and leading to major repairs down the road

  2. You can learn to tell if you’re affected, by reading below, or you can call us for a diagnoses & free estimate

  3. Our brand of choice, James Hardie, has a whole line of fiber-cement products designed for this climate — Hz10™. Which means it is absolutely built for the long-haul and offers great 15-30 year warranty coverage throughout their lineup — not to mention our own 7 year workmanship guarantee

Wet Rot : The Unseen Expense Nobody Warned You About

If your home is 10 years old or more, you’re likely in danger of unexpected expenses. 10 years ago the building codes for the states of Washington & Oregon were not what they are today. Leaps and bounds in building code revisions have been made to address energy efficiency, ecological concerns and longevity for improved durability in residential homes and commercial construction. In late 2020 the state of Washington is set to roll-out another set of revised standards for new construction projects moving forward, however no additional protections will be enacted to protect homeowners with existing flaws or shortcomings.

Step 1 : Knowing the components that make-up your home’s exterior and their approximate age

If your home was built in 2010 or prior - you’re likely living in a home composed of OSB, often referred to as particle board (Oriented Strand Board or OSB is a type of particle board; but there are others including MDF or Medium Density Fiber and HDF or High Density Fiber). Many homes 10 years old or more utilize OSB sheathing when constructing the exterior of the home - unfortunately some in the industry still utilize osb sheathing to cut costs while sacrificing quality to build more inexpensive homes.

As industry professionals we know that the savings new homeowners experience upfront almost always circle back around to bite them (you know where) later down the road. We strongly recommend that if you want a home truly built to last, go with a builder that utilizes plywood sheathing. The superior materials make for a superior product and allow homeowners to rest more easily knowing their home is well protected. Alas those home-builders can be a rarity.

For all of the other homeowners who haven’t had the luxury of building their new home with kiln dried, pressure-treated plywood sheathing — we’re here to help.

Step 2 : If you’re not sure about the components or age, the signs that rot may be occurring under the surface are subtle - but with some training they are noticeable

Some of the most noticeable signs of unseen rot are when caulking fails and/or trim appears frayed and ‘dirty’ on corners or on horizontal planes.

In the image above you can see that part of the caulking used to create a seal has failed, meaning it’s lost its adhesion and its ability to protect the seam from moisture. The main takeaway from this is that the caulking has allowed moisture to penetrate what should be your home's protective barrier. For more information check back again for our other blog post, ‘Caulking Failures : The Chink In Your Home’s Armor’.

In this image you can see the subtle fraying and deterioration of the vertical trim boards. This issue is found most commonly on horizontal trim — but can be found on vertical trim | at the bottom of the board if it creates a perpendicular alignment with another horizontal board.

The reason for this is that the horizontal and bottom of the vertical boards are where the most moisture accumulates. Often rain or snowmelt hits directly on the horizontal trim, splashes up onto the lower part of the vertical board and remains there until it evaporates. Repeating this cycle thousand or millions of times over the course of a number of years can lead to deformation and exposure. The takeaway here is that wood rots, so if your home isn’t properly protected your trim or sheathing will rot and break away.

When water penetrates the cracks in trim, which is exposed by caulking failure it heats and cools, creating a cycle of evaporation that rots the wood trim but also does a number on the weather barrier. The cycles of evaporation speed up the degradation on your barrier and cause it fracture, crack and peel.

In this image you can see the weather barrier, which looks like a black paper, is torn away - exposing the OSB wall sheathing to moisture. The takeaway here is that when your weather barrier fails, you can’t see it. It’s inside your exterior wall, you likely won’t know anything is wrong until something expensive happens.

OSB, and other forms of particle board, are particularly vulnerable to deterioration because the many layers act as a sponge for the moisture that penetrates the weather barrier. As the intrusion and evaporation cycles continue, more and more wall sheathing is compromised - which can lead to huge costs and a real hazard for homeowners.

In this image you can see the exterior trim of the home. Yes it looks a little old and a little weathered, which is normal, but on the inside you can see that rot and mold have been eating away at the wood. At this point it is completely compromised and needs to be replaced. If our client had left this unattended for a longer period of time, the trim replacement could have ballooned in cost and become a more serious home repair.

Step 3 : If you want the most well-trained eyes to complete an evaluation or if you suspect there may be an issue with your exterior and want a second opinion

Feel free to reach-out to our team anytime. We’re ready to answer your call with 30+ years of combined experience in diagnosing and correcting even the smallest issues - before they become big issues.

Call Today for your Free Estimate :

360-718-8694 or email

We use the James Hardie family of products which include HardieTrim™ & HZ10™ which are covered by 15 and 30 year warranties respectively. You can read more about James Hardie here.


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