Originally Posted by RTROSE
I have never used steel before. Is there weight limitations when using steel studs? Such as say hanging a plasma from the wall? I have heard that steel is not as "sturdy" in this regard unless you reinforce the metal studs. Is this correct?
Steel framing weighs 40% the weight of wood (average). One of the primary benefits of using steel is the straightness of the stud. Also, steel doesn't provide a 'food' for mold nor does it contribute to a fire. Once installed it's at least as sturdy as wood since it's held to the same standard in the building codes. That said, some of the installation details may be a bit different so blocking (or reinforcement) may be appropriate if the plasma is heavy enough.
Once steel is in place and the full load applied to it, it wont change shape over time. Wood on the other hand will deflect more as time passes. Even the building codes have "load reductions" based on the load (33% increase for wind loads, 15% increase for snow loads etc.). What that means is wood can support a greater load over a shorter time (lesser load over a longer time). You can see the effect of this over many 2-car garage doors. In a new house it's usually visually straight but over time long openings like this tend to sag. You can usually see the sag quite easily. By contrast, if steel doesn't 'sag' initially, it wont change over time.
To the question of lumber quality - Today's lumber quality (or lack of it) is caused by a couple primary reasons. First, plantation trees (trees planted and cultivated to grow very quickly) have much less tight grain than old-growth trees. By nature they will tend to want to 'bend' more because there are less 'opposing' grain to help maintain straightness.
Second is the moisture content in the lumber. In the early 90's the lumber mills changed the max moisture content of the lumber. It used to be dried to 15% moisture content and now it's dried to 19%. The building codes call for a max moisture content of 19% at the time of installation
(more about this below). Any wetter and the lumber will support mold growth with a little heat available. While 19% moisture content should be acceptable, lumber will dry to between 8 and 12% once installed and equilibrium is reached. Therefore it may 'change shape' a little before it's "fully dried". Grain and knots and other defects in the wood all affect it's final shape.
To make matters worse, lumber mills know that the lumber drying process continues over time. Since it takes several weeks or months to get through the supply chain and on the jobsite, they don't actually dry lumber to 19% but usually to something close to 23% or so. The 4% (or so) of moisture above 19% will dry during this time frame (usually). All this has a real noticeable effect on how straight the lumber is.
While they're are better quality lumber producers out there, the lumber yards buy their wood from the same mills. It really wont make a difference whether you buy it from Lowes/HD or a 'contractor yard'. What WILL make a difference is the quality of the lumber. Most times, the higher the grade the better chance it will stay straight (primarly because the lumber grading rules call for smaller/tighter knots and straighter grain for the higher grades).
So, if you haven't decided to switch to steel yet, the way to get straight lumber is to buy 1) the highest grade possible (#1 or Select Structural grades if available); 2) as dry lumber as you can (every board should have a grade stamp on it - a KD19 means 19% lumber, KD15 means 15% - the other number on the stamp is the mill identifier); 3) a specie of lumber less prone to warping (SPF - Spruce/Pine/Fir - is likely available in most parts of the US. It tends to be straighter than SYP - Southern Yellow Pine or DF - Doug Fir.)
Other options are using engineered lumber but that will likely mean a special order. LVL (laminated veneer lumber) or PSL (parallel strand lumber) 2x4's are available but will certainly be more expensive than typical framing lumber. As mentioned a finger jointed stud is less likely to warp too. They should be available in most markets but likely difficult to find in retail stores.
A steel stud is also a good option. Steel studs bought at Lowes/HD are going to be 25 gauge studs (typically called drywall studs) meant for non-load bearing interior walls (no load from above). They are acceptable to hang light loads on. You should have no problem hanging all but the largest/heaviest plasmas/LCD's. A toggle bolt or using blocking (even wood blocking) in the area where the mount is located should work. Heavier gauge studs (and track for top/bottom plates) are available at most drywall supply stores (whether than sell to the general public is variable). Pancake head self drilling screws make installation pretty simple. Drywall can be screwed to the stud and trim can be 'shot on' with pins designed for steel studs (available for most applications and for many of the most common air nailers).
Hope this is helpful. I spent more than 20 years in the wood building component business before I made the switch to steel about 5 years ago. If anyone needs more information please feel free to PM me.