Metal building erection standards

[brickmaker]

I have a plant expansion project going which involves the erection of several large pre-engineered VP buildings. My questions are as follows:
1 - How many "opps" screws as described by VP should be acceptable per acre of roof? This is a special screw to put in a misdrilled hole where the purlin is missed. Our contractor is making a rather free use of this repair concept.

2 - How many dented panels (crimped ridges) would be acceptable on the same building?

3 - Are there standards for these two items?

 

[brian88]

1. A pre-engineered metal building, such as VP, does not use the roof panel as a diaphragm. It uses it to either brace the top flange of the purlin or semi-brace the top flange of the purlin. Therefore, the "opps" screws is merely a weather-tightness issue. It shouldn't compromise the structural integrity of the building. I would definitely question if they are authorized to install a VP building.

2. Dented panels are definitely a concern, especially if they are creased. I usually would make the contractor replace a damaged panel especially if the rib has sustained significant damage. The majority of pre-engineered panels gain their strength from the rib. If the dent is located in the pan of the panel, I would make sure the coating is not damaged and the dent will not cause ponding. If either of these are an issue, the panel will rust and ponding could cause failure.

3. I am not aware of any standards for these cases but Varco-Pruden should have a department that handles the warranty on their buildings. Definitely, talk to them about this because it sounds these buildings will eventually have a weather-tightness issue due to the below standard construction.