Wrong materials for our climate

I was called to a spectacular residence last week. A house on a bluff overlooking the Willamette Valley and Mt Hood. The owner is a retired contractor. As I have said before, many contractor fear working for other contractors and architects. I find it a privilege and a challenge, they are the most knowledgeable clients and the most demanding. If done right it can be a rewarding partnership. The issue I was called to review was a failing beam that ran right through his house and to the outside to form the support for a second story deck. This beam had been in place for just 15 years. A beam should not fail after just 15 years, there are beams all over the world that have been in place for centuries, even millennia. So something is very wrong. Several things concern me about what I saw.
  1. This beam supports a deck that could have several people on it at a time.
  2. The beam is not a pressure treated or exterior quality, nor is it coated with a product to give it any significant weather resistance. It is exposed to the elements in that location (snow, ice, wind and rain)
  3. The beam has previously been "repaired" by another contractor. He simply tacked fir (not pressure treated) 2x4's along the outside of the beam and painted them to match the house. These have rotted too.
  4. There is no flashing above the beam or the posts on the outer edge of the beam. While this is not required by local code it is good practice to prevent moisture penetration. These posts are cased with some elegant wood casing, but when tapped with a screw driver it was found that they are rotten and quite literally full of water.
My solution here is to do the job right once and for all.
  1. Remove all rotten components.
  2. Remove the beam back to just inside the exterior siding on the house.
  3. Lap join a new pressure treated beam to the existing beam leaving only pressure treated beam exposed to the elements. This beam will need to be joined using dowels and weatherproof adhesives. It will also require sealing around the beam with  a suitable weather resistant sealant.
  4. New pressure treated posts need to be installed with flashing on the post tops to prevent moisture penetration.
  5. The tops of all surfaces of the deck structure need to be flashed to prevent moisture penetration.
  6. All surfaces need to be painted or varnished to protect against moisture penetration.
Doing a job right the first time always costs less in the long run. Having to replace structures prematurely adds a layer of cost to home ownership that should not and usually does not come into the math when people determine the cost of home ownership. Faulty workmanship is everywhere, it is the responsibility of builders, home inspectors, city inspectors and home owners to police workmanship and make sure things are done right the first time. If you are unsure of how something should be done ask questions and do a little research on the topic - it pays dividends.
This entry was posted in Best practice, Project Tips.

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