1. Wider/longer bay spacing, usually 20-25 feet. Set for door openings.
2. Optional pre-framed windows and doors.
3. Low roof pitch, normally suggesting 1:12; some say it looks better.
4. 26 gauge sheeting; thicker.
5. Fewer frames to erect, effecting contractor’s time.
6. Less concrete due to lower number of piers and although in many cases fixed connection (which will offset some of this savings).
7. Insurance may be better as a non-combustion building.

DISADVANTAGES:

1. Worst possible building for collapse in case of fire. Fire Department will not normally enter the building.
2. Bolts are used instead of tek screws to apply the purlins and girts. So excess snow or ice levels, or excess wind up-lift causes the building to stretch, twist, and could collapse down as the bolts will not give.
3. By using 26 gauge sheeting, and the low roof pitch, they generally require the use of caulking which will dry out, shrink, crack and results in eventually roof leaks.
4. By using 26 gauge or 24 gauge sheeting, with purlins on 48 inch O.C. (or more), the allowable uniform load is much less compared to purlins with 24” O.C. or less spacings.
5. A tek screw is used to fasten steel sheeting to steel purlin (vs. steel/wood), resulting in potential for up to 100%leaking as steel will not absorb water.
6. The plate steel type frame is very wobbly or flexing during the erecting stage and requires a great deal of bracing during construction.
7. To finish the inside with drywall or plywood, requires the application of strapping as the girts can be 48” to 84” O.C. You’re actually building another building inside to finish.
8. The fixed connection uses 10-15% more concrete in piers and is a less stable construction design, providing an overall limiting design safety factor.
9. Most all steel building manufacturer/suppliers offer only a ONE YEAR warranty.
10. Typical application of insulation is a squeezed fiberglass option – offering a much reduced actual R- value and absolutely no reflective protection from radiant heat, unless covered with foil.

1. Trusses are closer together, usually 4’ to 6’ O.C. and very seldom 8’ or more.
2. Metal roof is screwed to wood purlins. Chances of leaking is almost nil.
3. Easier to put in windows and doors with wood girts than steel girts.
4. Can easily make decisions on windows and door openings after the roof is installed.
5. Wood is more acceptable as it reflects a comfort zone in building or framing as in a “home”.
6. Wood is a non conductor of heat/cold and is a good insulant and thermo break product.
7. Easier to find home builder type contractor vs. steel erectors for the building. Less costly per hour for labor and for lower rates on workman’s compensation insurance. Also trades to work with wood are more readily available.
8. Note: If steel was really that great then the home industry over the past 25 years would have captured more than the ¼ of 1 percent market share they have now.
9. Wood is warm and more comfortable.

DISADVANTAGES:

1. 1. The purlins are applied horizontally, not vertically, causing a wavy roof system.
2. The wave of the roof stretches the metal causing screws or nails to pull out.
3. Trusses being 4’, 6’ or 8’ O.C. makes for a good landing pad for the birds to perch themselves on and make a mess of the inside of the building.
4. With wood trusses, there are limitations to head room if and when needed.
5. Columns are not engineered causing not much security with high winds and snow.
6. Columns 6’ to 8’ O.C. there is no chance to enter in the side of the building with a 10 or 12’ door or wider.
7. Frame assembly and erection typically requires extensive bracing and/or tie downs to prevent collapse until purlins are installed and metal is on roof.
8. Under fire you can open the roof to rid the excess heat will help but usually entire building is lost.
9. Non-engineered columns can collapse due to heavy uplift wind, snow/ice loads or fire.