Here we see a typical low-rise building in Hawaii, built decades ago with a CMU block guardrail system. While these block walls were once thought to be very durable, they actually become a maintenance nightmare after many years of exposure to weather and chlorides.
Not only can the corrosion of the rebar within the wall cause the block to crack, it can also make its way down to the concrete lanais - causing the slab edges to spall.
If maintained, costly block repairs can be kept to a minimum, and repairs to a building's slabs may not be necessary. However, if the spalls are left to grow and spread throughout the wall, there eventually becomes a point where the demolition and repair of each block becomes far more expensive than replacing it with a brand new aluminum railing system.
Here you see the demolition of the existing block walls. Unfortunately, upon removal we uncovered severely corroded rebar dowels spaced 12" on center within the lanai slab. To prevent further decay, we chipped out the concrete around these corroded rebars, removed all rust, and coated the steel with a corrosion-inhibiting epoxy.
Once all concrete spall repairs were completed, we installed a new Railcraft Aluminum Railing System with tempered safety glass panels. The owners chose a corrosion resistant, D3000 champagne powder coating (AAMA 2605 certified), to match their upcoming paint project. The lanai slabs were then coated with the Neogard Pedagard elastomeric waterproofing system to prevent any future deterioration to the newly repaired concrete.
This building upgrade has increased the property value for the building owner and even better, increased the rental income he receives from his tenants.