To avoid the wear and tear of gang nail plates, Outside Products recommends bolted steel connection plates for exposed timber trusses.
Gang nail plates in trussed timber pedestrian bridges are a fairly cheap connection method that has an inherent fault - gang nail plates don't stay in timber when exposed to the weather.
Gang nail plates work extremely well in residential construction because the timber is protected from the weather, however, when they are used outdoors, the natural expansion and contraction of timber grain actively pushes the plates out of the timber.
Outside Products, one of Australia’s leading manufacturers of bridges, shelters and other park infrastructure, believes that trusses should be protected from the elements to ensure the plates don't suffer from this problem, and in turn lead to structural movement or total collapse. The liability issues here are too great to ignore.
While some companies try to overcome this problem by adding screws or flat head nails in an attempt to hold the plates in place, Chris Breed, Director of Outside Products, believes it is better to avoid them altogether for exposed situations.
“Bolted steel connection plates are the best solution for exposed timber trusses. At Outside Products, we use 4mm thick steel plates to bolt each member to the next, avoiding the possibility of gang nail plates working loose over time. It does cost a bit more upfront, but the longer term benefits with maintenance, repair or total product replacement see the money well spent,” says Chris.
Councils around Australia need to justify to their constituents that the best product for their money is being purchased on behalf of the public. Lower long term maintenance costs and extended periods between replacement help to make that task easier.