[thekremlin]

When adding length to a post, consider that the post is subject to two kinds of stress, vertical or load-bearing stress and horizontal or shear stress. Depending on the location and length of the addition, it's usually better to completely replace the post if possible. If it's a repair you're making, or the lengthening is not substantial, you can connect the post with another section of wood using a rabbet or half-lap joint -- sometimes also called a scarf joint. This type of joint supports the post vertically and horizontally, counteracting the shear effect to a certain degree. Doweling is another way to add shear strength. Post caps and metal plates are another way to lengthen posts. Add a wooden sleeve overlay to any of these methods, and the post should be strong enough to do its job.

[whiterabbit]

Dowels are often used with good results to join two pieces of wood together. For posts, use an appropriate-sized dowel no smaller than about 1 to 1 1/4 inch in diameter. Drill one hole at least 3 or 4 inches deep centered vertically in the end of each post. Apply glue to the holes, hammer the dowel into one hole, fit the exposed end of the dowel into the corresponding hole in the other post and tap the two pieces together with a mallet. Toe-nail screws through the joint on all four sides for more integrity. Dowels help to align the pieces and add shear strength. Beef up the dowels by adding 4-by-4 metal plates or a wooden sleeve to each side. [links]

[Karmicads]

Maybe you forgot to measure twice and cut once. Or you're down to the last post and it's not tall enough. Perhaps you trimmed damage from one end of a post. Whatever the reason, if you come up short on the required length for a deck post, you can lengthen it in a variety of ways. Before you start work building or remodeling a deck, check local building codes and make sure to follow them.

[tfoote]

Post caps are sometimes used to join posts together. Post caps come in different configurations, but for post joining applications, the post cap should have two equal sections or sleeves: One side slips over the end of a post on one side, and the other portion slips over the post at 90 degrees on the other side. The two sections are bolted or screwed to both posts with drilled holes in the cap sleeves. This is the quickest way to joint posts end to end, but it's also the weakest. Post cap joinery should be followed up with wooden sleeves for best results. For the wooden sleeve to fit properly, cut a shallow channel perpendicular across the post so the sleeve fits flat against the post, with the metal leaf inside the channel when the sleeve is screwed in. [links]

[Marko]

Deck framing is the most common area for rot damage on an old porch.

[riggasconi]

Before about 1860, deck frames were often built of large logs called “sleepers.” These sturdy logs were hewn flat on one or two sides, with one of the flat side facing up to act as floor joists.

[throughput]

Whether turned or chamfered, porch posts support the roof-framing system (a topic for another story) and act as anchors for attached railings. If they’re made of old-growth wood and positioned correctly, they should last indefinitely—provided they are properly ventilated.

[alowm]

It would make thousands feel better about their construction abilities. [links]

[komoto]

My question is would it be best to join the second set of 4X4 posts at the tops of the first ones by ‘girdling’ them around with some sort of structure that ’embraces’ the splice … also employing a simpson strap — OR — would it be best to cut the 16″ off down to the deck level .. sheeth the top of the post over with the 3/4 t&g flooring .. and establish a new post rising up from this solid deck surface?

[offtomalta555]

If your hair looks funny, it's because God likes to scratch his nuts.  You nut, you.

[enoxice]

As long as your architect is happy with the calcs that say 4x4's will be sufficient to support two decks..

[emmamarko112]

your tr area must be less than the max allowable tri area

[GoldRush]

Take a deep breath and calm down. People here are actually trying to help you. more

[impossible7]

POST REMOVAL TIP: Naile a 6″ scrap 2×6 to the post and use a long rock bar and fulcrum to lift the post out of the hole. here

[corwin78]

We used 2×6 stock and doubled them up, installing them under the main barn beam. These supports carried the roof and beam weight while we worked on the posts. We focused on the most rotted and sometimes completely rotted and non-supporting posts first, leaving any semi solid posts to carry the load of main beam and roof load.. more

[DrWatson]

We took pains to dig all of our footing to a 48″ depth, below our fronst line. here

[miernik]

Once all of the bad posts were done we then replaced the solid posts but did so in an alternating fashion. Leaving a solid post in between two repairs, as a redundant back up to our temporary supports. more

[ruano]

The old siding was tongue and groove pine boards. The old boards were not back primed and had rotted. As a replacement I choose to replace that siding with T&G cedar, vertical grain siding. I also paid extra to have these boards primed by the factory.