Tag Archives: exposed screws installation

Dear Pole Barn Guru: Do You Have House Floor Plans?

Welcome to Ask the Pole Barn Guru – where you can ask questions about building topics, with answers posted on Mondays.  With many questions to answer, please be patient to watch for yours to come up on a future Monday segment.  If you want a quick answer, please be sure to answer with a “reply-able” email address.

Email all questions to: PoleBarnGuru@HansenPoleBuildings.com

DEAR POLE BARN GURU: Could you send me some house floor plans that you have made or that you have? We just are not very good at coming up with the sizes. We have looked at a double wide house that we really like but we are not sure if thats something we could find and some how send to you. BAFFLED

DEAR BAFFLED: As we provide the structural building shells, and not any non-structural interior walls, we have no “house floor plans”. A good way to come up with sizes is to take a tape measure to the rooms in the house or apartment you live in now. Same with the double wide you liked – go measure the rooms. Do paper cutouts of different pieces of furniture (to scale) and place them on rooms drawn to scale. There are also numerous FREE room planning tools on the net. One source is: https://freshome.com/2010/08/18/10-best-free-online-virtual-room-programs-and-tools/

DEAR POLE BARN GURU: Where do I place screws for exposed fastener applications? SCREWED IN SCHENECTADY.

DEAR SCREWED: A properly installed screw will be down in the flat of the panel. (Some companies errantly install them on the high part of the ribs).  At this location the steel panel has solid wood right below and good compression on the washer can be obtained. With thermal movement in the panel, the screw will be put into shear, not bending, and the hole thru the steel panel will slightly elongate.

When we tested full sized roofs, under controlled laboratory situations, we found repeatedly cycling horizontal loads (which simulated wind) into the roof system, also caused the holes in the steel panels to elongate, when using the industry standard #9 or #10 diameter screws. The mechanical engineer, Merle Townsend, who did our testing, designed the “Diaphragm screw” as a result of this actual testing.

As long as this slot does not exceed the diameter of the washer, the hole will remain sealed. In order to prevent undue slotting, only “Diaphragm screws” should be used to attach through screwed steel roofs.

Additionally, the diaphragm shear capacity and shear stiffness is based on the screws being installed in the flat of the panel. If screws are installed in the top of the rib, the diaphragm would be much more flexible and would not be as strong.

DEAR POLE BARN GURU: Do you sell metal trusses?  If not, can you recommend someone?  We live in Hastings MN. HARRIED IN HASTINGS

DEAR HARRIED: We do not. We’d need to know more about how you anticipate using them, to be able to give you a better idea. Unless you are looking at a tremendously huge span (over 100′) steel trusses are generally not cost effective.

For relatively small span residential and commercial applications, where trusses will be placed every two feet, some metal connector plated wood truss fabricators are also offering light gauge steel trusses.

In some parts of the country (especially Arkansas and Alabama) there are a plethora of folks who manufacture welded up steel trusses made from angle iron and rebar. There may be some questions as to the engineering and integrity of these products, as most of them are utilized in buildings which do not require building permits.