Why decks fail at the connections
A deck or balcony is the one part of a building designed to stand in the rain. The Wood Handbook names porches, exterior steps and decking platforms among the places where preservative-treated wood or a naturally decay-resistant heartwood is advised, because these members are wetted directly rather than by vapour. Where the original build used ordinary framing lumber behind a coating, the coating is the only thing keeping the wood below the fiber saturation point.
A pest report has to say something about every wooden deck, stair and landing. The pest control regulations require that information be reported on any wooden deck, wooden stairs or wooden landing in exterior exposure attached to or touching the structure inspected, and they list porches, patios, steps and stairways among the accessible areas. So the report an owner already holds usually names the members this work replaces.
Taking a balcony apart removes its guard, and the rules for the open edge are specific. Cal/OSHA's construction safety orders require railings along all unprotected and open sides, edges and ends of elevated platforms and surfaces 7 1/2 feet or more above the ground or floor beneath, with a top rail 42 to 45 inches high and a mid-rail. Where railings are not in place, personal fall arrest, restraint or positioning covers anyone exposed to a fall of more than 7 1/2 feet from the perimeter of a structure.
Posts and stair stringers rot from the bottom. Where a post sits on a slab in contact with earth, or a stringer lands on grade, the wood is in contact with wet ground, which the Wood Handbook names as one of the few ways wood reaches the fiber saturation point. The pest rules count earth-wood contact and faulty grade as conditions likely to lead to infection.
What deck and balcony repair includes
The deck or balcony is walked with the report in hand, each listed item found on the structure, and the members probed and metered. Where the report marks an area as inaccessible or for further inspection, that is the first place opened, because the soffit hides the ledger.
Temporary railings go up at the open edge, or personal fall protection is used where they cannot, and the element below is closed to residents for the duration of the removal.
Decking, membrane and soffit come off, and the joists, ledger, posts and stringers are cut back until the tool meets wood that is sound rather than crumbling.
Each member is removed or left with a second member installed alongside it, which the pest regulations allow only where both are below twenty percent moisture and the wet condition has been corrected. New fasteners against preservative-treated wood are hot-dipped zinc-coated galvanized steel, stainless steel, silicon bronze or copper (CBC 2304.10.6.1).
The membrane over the frame and the flashing at the ledger are rebuilt, so water leaves the assembly instead of sitting on the joists. Enclosed framing behind a soffit is rebuilt with openings giving at least 1/150 of each space's area in cross-ventilation (CBC 2304.12.2.5), so the next leak dries instead of festering.
The guard is rebuilt, the surface finished, and photographs of each member with the moisture readings go into the file against the report's item numbers.
A balcony is not repaired until the water that rotted it has somewhere else to go. Replace the joists and leave the membrane as it was, and the same members are back on the next report.
Where decks and balconies fail
Three-storey walk-up apartments
Cantilevered balcony joists run back into the floor inside, so rot that starts at the edge travels toward the unit rather than staying outdoors.
Garden and townhouse condominiums
Shared walkways, landings and exterior stairs carry every resident on the building, and their inspection cycle runs under Civil Code 5551, as the balcony inspection guide sets out.
Motel exterior walkways
Open walkways and stair stringers take weather and constant foot traffic, and the work is sequenced around rooms that stay occupied.
Older raised-foundation houses
Wooden porches, steps and landings sit close to grade, and the pest report lists them as accessible areas that have to be reported on.
Restaurant patios and decks
Raised dining decks and their rails take spills, washdown and rain, and the frame under the boards is rarely opened until something moves underfoot.
Ranch and agricultural buildings
Posts and sills set in ground contact or embedded in concrete stay wet from irrigation, and the wood at the base goes long before the rest.
Questions about deck and balcony repair
Not the one being worked on. The guard comes off with the framing, so access is closed while the element is open, and the work is sequenced so that one stack at a time is out of service. Where an inspection report found an immediate threat, both balcony statutes require access to be prevented straight away.
Further than the report can say, because the report is written from what could be reached. The pest regulations treat the space between a deck and the ceiling or soffit below as an area an inspection cannot enter, and list further-inspection items separately. Opening that space is the first thing the estimate allows for.
The building department for the city the property sits in takes the application, and the pest regulations say that where the inspector considers a permit is required, that has to be noted on the report. The contractor assigned to the request pulls it.
Sometimes, where the boards come up without damage and the frame beneath is what has gone. The pest regulations allow a member with only surface fungus damage to be chemically treated or left as it is, in the inspector's opinion.
The report names the items, and what is opened on site settles the rest. Each line in the estimate is keyed to a report item, with replace or sister stated against it.
Deck and balcony repair by city
Deck and balcony repair is requested through the dry rot repair page for your city, which names the stock and the permit department there.
Related dry rot services
