COASTAL DECK

Designed and built to allow the homeowner to enjoy the ample afternoon sunshine, a valuable commodity in the Pacific Northwest. As it was being built off an existing structure clad in weathered shaker shingles, we decided to use a vinegar based solution to age the cedar to better match its setting.

SUBSTRUCTURE

The substructure was erected with no issues, using standard pressure treated lumber, supported of 12” diameter piers formed using Sono tube. Having refinished a fair share of decks over the past couple of years, we have noticed certain failure/rot prone spots. Because of this, an adhesive flashing was used to cover the joists to help ameliorate standing water and the inevitable rot that results (even in treated wood). In this vein hidden fasteners were also employed, as they remove another potential failure point created by the screw holes on the top of the decking boards (with the added benefit of a more aesthetically pleasing end product.)

wOOD TREATMENT

As mentioned before, a vinegar and steel wool solution was applied the the cedar to create an aged look before sealing. This process could be extremely tedious at times, especially when it came time to spray down all four sides of the 160 balusters. Yet, despite the time investment, the end product was undoubtedly worth it as the process not only drew out incredible colors unique to every board but also tied it in nicely with the existing house. After letting the wood thoroughly dry (by PNW standards anyways) Penofin Marine Oil was used to seal the wood on all sides before installing. This process again is an attempt to address the rot areas we have found from taking up old decking.

Railing Design

This was the portion of the build the required not only the most time, but also the most design considerations. Railings are traditionally the weak point of decks, while at the same time being the most important safety feature.

If I were to ask you to take a look around your neighborhood at how posts are attached, I would guess the about 90% of railing posts are attached to the outside of the rim joist using two large lag bolts to hold them in place. While this may allow for sufficient outward pressure strength when the deck is first built (though many times this is not even true) as the deck ages and the wood begins to weaken via exposure, these joints are nowhere near strong enough. Current Code requires that the post be able to resist a 200 lb force applied anywhere along the top rail. In order to achieve this (for the life of the deck) the posts were spaced 6’ apart and were affixed with substantial blocking on the inside of the rim joist. Four 6” Timberlok lag strews were used to fasten the posts.

After dealing with the post, the next thing to consider was standing water. Again, go look around your neighborhood at the top railing of some of the older decks. warping and sagging seam to be the name of the game here (in regards to wooden railings of course). Part of this could be attributed to cheaper woods being used who rely on a paint coating to keep off the water. More importantly though it is in the basic shape design of the top rail, a flat surface on which water is encouraged to sit and find its was into the rail. To combat this we ripped a modest 15 degree slope into the top rail, promoting water to drain rather than stand. This should not only help in making the railing last, but also has the added benefit of a much more supple feeling under hand.

Last but not least was baluster design. Again, this is one of the weak spots as decks age, water and UV damage degrade the wood to the point were a single fastener system will generally not be sufficient to meet building code requirements (for reference balusters must resist 125 lb outward pressure applied over a square foot). To this end, the balusters were sandwiched between four rails and capped with a 2x4. The bottom was left open to allow for water drainage.