Dan Watson goes over the art of replacing rotten beams on a seaside condo by the southern coast of New Jersey. The wind-driven rain and high humidity in the area provided the wood on the condo a tough environment. The weather doesn't allow for adequate drying time. The trick on this beam renovation was not only waterproofing the home, but also creating a pathway for the water to drain and allow for air to flow over the wetted structure. This promotes drying.
Upon initial inspection, Watson and his team discovered mold, leaking, and rotting in the beam under the capping of this home. They had to remove the cladding from the balcony beam as well as throughout the exterior of the home.
As Watson writes for our sister site the Journal of Light Construction,
A consulting engineer was hired to examine the beams and surrounding structure to determine which beams needed to be replaced and which were still structurally sound. In the final tally, nine engineered beams and two dimensional-lumber beams had to be replaced. Based on the engineer’s findings, one of the unit’s beams was so deteriorated that the structure was deemed unsafe to inhabit and would need to be temporarily shored for the rental season. The engineer provided a temporary shoring plan, and we were able to support both the balcony and the third-floor bedroom without limiting access or use of the areas…
Removing the beams required cutting through a lot of nails, many of which were hidden or difficult to access. In the upper beams, there were toenails that secured the trusses above and the 6x6 posts and king and jack studs below. A couple of the beams also held drywall screws, which led to drywall repairs and repainting on interior walls.
On the lower beams, we removed and disposed of the hangers, as well as toenails, that secured the balcony joists. (We would later replace them with stainless steel hangers and fasteners because we were close to the ocean.) The plywood for the fiberglass balcony was nailed into the top of the beam, and finish nails secured a 1-by fascia board to the exterior face of the beam. The beams sat on bearing walls at each end and were nailed off to these wall plates…
To protect all the new beams from water and prevent a repeat of the rot, we installed Home Slicker, a matrix-type rainscreen, to the exterior side of the beam. We then installed 2-inch-wide strips of 3/4-inch marine plywood before attaching a 2x8 band. This assembly allows for unrestricted water flow for rainwater or snow melt that makes its way past the siding and flashings, and it provides plenty of room for air flow for drying.