One advantage of purchasing a pre-engineered steel building is a quick and efficient construction process. Whether you choose to do it yourself or hire a professional, there are several steps to follow while erecting your steel building.
During the erection of a metal building, it’s important to follow the safety and procedural guidelines set for by the Metal Building Manufacturer’s Association (MBMA) and the Federal Occupation Safety and Health Administration.
Step #1: Foundation
After ordering your building, you’ll receive a detailed drawing which includes all the parts of your building and how they fit together. It also Includes anchor bolt plans for the foundation engineer to design the foundation.
The most important thing is to keep the structure plumb and level. Before erecting anything, make sure the foundation and the anchor bolts are properly laid out. Measure the 2 diagonals to make sure they’re equal. Then, check the distance between anchor bolts by measuring from the center of each bolt and compare them to the figures in the plans. After determining that they’ve been properly placed, clean any concrete off the bolts.
Before you attach columns to the bolts, make sure you have enough nuts and washers. Don’t leave a column standing with loose or missing nuts.
Step #2: Main Frames, Purlins
Always work from the inside out and erect and secure one bay at a time. For a two-bay building, erect the center frame and an end wall first. For a multi-bay building, start with the middle bay, or the first x-braced bay, if present. Stand the columns and use a four-foot level to check them. If necessary, shim the columns to level them. If you plumb each connection as you make it, you will save yourself a lot of time and trouble later.
As soon as you have all four columns of the center bay standing, install the sidewall girts at 7’ 6”. Assemble the two rafters making sure the connections are fully tightened. Raise the rafters, make the haunch connections, install the eave struts, the two peak purlins and then the intermediate purlins. Finish framing this first bay. Tie it off with ropes and come-alongs to create temporary x-bracing and then make sure it is plumb.
If your building has more than four bays, install temporary bracing on every fifth bay. Leave this bracing in place until the walls are sheeted. Check your framing with a level each morning in case the wind has shifted it overnight.
After erecting and plumbing the frame, install the flange bracing. Continue erecting bays in the same sequence: columns, 7’6” girts, rafter frames, eave struts, purlins and remaining wall girts. Until the walls are sheeted, the frames can move from side to side, so leave bracing in place to keep them plumb and square. With the frames and end walls in place, you can then install the base trim.
Attach the base trim to the concrete on two-foot centers. Use nail pins or sleeve anchors. Shoot-in anchors are not strong enough. To install building accessories, simply follow the instructions that come with these items. Before sheeting the walls, attach the jamb and header trim to the framed openings with pop rivets.
Step #3: Wall Sheeting
Now it’s time to do the walls. Prepare the sheets by pre-drilling holes for the stitch screws and structural screws. Make a template by carefully drilling the holes in one sheet. With this guide lay out stacks of up to 15 sheets, stack them and carefully drill holes. After drilling, wipe away the metal shavings to prevent rust.
Next, lay out the insulation and cut it into sections as described on the cut list. Finally, attach double-sided tape on the base trim and the eave struts. Start on the back wall so the crew gains experience before moving to more conspicuous parts of the building. Begin at a corner and install a section of insulation with the exposed fiberglass facing the outside of the building. Stretch the section tight over the eave strut and the base trim using the double-sided tape and clamp pliers to hold it in place.
Fiberglass insulation will soak up or wick any moisture it touches. You can prevent this by leaving no exposed fiberglass. After clamping a section, you should have 6” extra insulation at the top and the bottom. Trim away the excess fiberglass but leave the vinyl facing intact. Fold this excess vinyl back over the fiberglass to create a moisture barrier at the edge of your building. With a section of insulation in place, install the wall sheet using the self-drilling fasteners supplied with your building. The longer fasteners with smaller threads connect the panels to the frame. The shorter ones with larger threads are called stitch screws and connect panels to each other.
Continue installing the insulation and wall sheeting according to the pattern in your drawings. Use your four-foot level to check each piece of insulation and each wall sheet as you install it making sure all are plumb. Cap off sidewall panels with eave trim before roof sheeting begins. Attach with 3/16” pop rivet.
Step #4: Roof Sheeting
Next comes the roof. As always, safety is the most important thing. Wear masks and proper attire when installing fiberglass and follow approved procedures for working off the ground.
Start by laying out the roof sheets. Pre-drill for the stitch screws and structural screws. Lay out and cut the insulation. Attach double-sided tape to the inside half of the top of the eave strut, leaving room on the outside half to place a closure strip. Stretch out a section of insulation, facing the tab in the direction you’re sheeting, pulling it as tight as you can from side to side and attaching it to the eave strut with the double-sided tape and clamps.
As you did with the walls, cut off any excess fiberglass on the top of the eave and fold the vinyl facing back over the fiberglass. Install one run of insulation at a time, covering it with roof sheets as you go to keep wind from pulling up the insulation. You’ll seal each sheet with a closure strip which will create a watertight barrier if properly installed. Use the mastic sealer tape to attach the bottom of the closure strip to the eave strut just outside the double-sided tape that holds the insulation. Run mastic sealer along the top of the closure strip so you can attach the roof sheet to it. Do not remove the protective paper strip from the mastic until you’re ready to install the next sheet. As you seal roof sheets, do not allow insulation to be caught between them and the closure strip.
To properly align the ridge cap or vents, you must install the sheets in a specific order. Placing a sheet on one side of the peak followed by one on the other side of the peak and then the section of ridge cap that goes between them. On wider buildings or when installing skylights, the roof sheets will be in more than one piece, so install the sheet at the eave first and work uphill.
Refer to your drawings for the screw placements and the amount of overhang at the eave. As you proceed down the roof, the 6” insulation tab should go forward towards the next panel allowing the tab to cover the seam. If you’re using a radiant barrier foil, it has an adhesive tab on one edge. Simply pull the paper backing off the tab and attach the next sheet to it.
Step #5: Trim
After sheeting the roof, install the trim as described on your erection drawings. Use pop rivets to install the corner trim. If installing gutters, do not leave off any straps and before you cut holes for the downspouts, be sure you aren’t positioning them over a door or window.
At the end of each workday, sweep away any metal shavings caused by drilling or cutting and ensure decades of rust-free performance.
Remember, a quality job comes from taking your time, using your level and following safety rules always.