I have a cantilevered deck that was needing new decking boards. As it turns out it also has some dry rot on the joists that are cantilevered from the house (14ft high, extending 6ft from the house - a maximum of 2" X 12" joist according to OR building code bottom of page 7). I am hoping most of the damage is surface, but in order to to repair the joists w/o full replacement (as recommended here), I would follow the below laid out plan. In addition to the joists, the header joists also has small dry rot area. That would be a straight replacement of the said header joist. I would appreciate any feedback on the process. My brief research shows that best practice is to repair the dry rot, and sister the joists, hence the following plan.
- Remove dry rot
- Clean and re-fill the dry rot area with appropriate wood filler / epoxy (found it on This Old House)
- Add sister joists. [Should new sister joist be attached to house face with 4" X 12" joist hangers around existing cantilevered joist and the new sister joist?]
- Replace header joist [Shall I join this header to sister or the original joists?]
- Cover all joists/header with water barrier (joist tape or such)
- Install railing blocking
- Install new decking and railing
I have seen this advice:for sister joining, which has the OP wanting to repair some joists, while others advised replacement. In my case replacing the joists would probably mean much more work than having the small deck is worth, I think that joist sistering may be a way to go.
So any advice when tackling this task would be appreciated, especially on topics of sistering and maximum allowed joist notching.
Some additional resources:
When repairing joists - amount of removed material is of importance (of course), but what is the rule of thumb for sistering to be successful without compromising integrity? Notching is bad - what is allowed?