(If Albert Einstein was a Builder)

PSL – Plumb, Square, and Level
When you say “PSL” around here and maybe in your city too, everyone’s first thought goes to “Personal Seat License.” You know that ridiculous fee you must pay that gives you the right to buy tickets for events at a stadium near you. In this case, where I come from, I am talking about the Baltimore Ravens and M&T Bank Stadium.

No, I won’t let this turn into some diatribe about what us Baltimoreans know as the PSL, instead let me drop right into my topic for this piece. When I say PSL here I am using it instead as an acronym for the construction ideal of Plumb, Square, and Level. When you live and work in home improvement and/or building, these three things are your friend. Every nanometer that you move closer to these states, your life and the balance of it become much more true.

Ok, that might have been a little over the top and maybe even a little “mystic”, but the point is: When constructing anything you are very dependent on who, what, and how things came before you. Let’s for example say, while it is not totally impossible, it is certainly much easier to install a perfectly level tile floor over perfectly level subfloor. And it is much easier to install a perfectly level subfloor over joints that are true and perfectly level, and. . . ., well, you get point.

But let’s run with that. Plumb, Square, and Level are really only relative states. And this becomes all the more clear when you live and work in old houses. (I will get back to that in a bit.) But let’s think about it. Aren’t these ideals really just judged in relation to, well, the earth and the movement of time?

The earth and the world we live in
Plumb, for example, is the state or description of being perfectly vertical or perpendicular, yeah, to the earth. Level is the state or description of being perfectly horizontal or parallel to the earth. These things are true. But as Einstein might want to tell us, these things are also totally relative.

For us, our time-space curve here is drawn on a very localized scale. So stop. Think about it; Einstein was right. Everything, including those things we measure with tools and instruments, is relative, and must be viewed with that knowledge in mind.

Plumb and level: there, that takes care of two planes for us. Oh, but wait, there’s a third. That’s right, square. As if there wasn’t enough pressure for your home project already: Plumb, Level, and now Square. Yep, in my big monster truck voice, “It’s in 3D Dee Dee Dee. . . .” As level and plumb as you can make things, they won’t be right unless they are also perfectly square.

And what is square? Well, other than that cat who doesn’t smoke cigarettes, of course, a square is a shape. A square is, in fact, a polygon (meaning it has multiple sides) for which all angles are 90 degrees. These angles are called, strangely enough, right angles.

Enough with the geometry, and in the fear that this might turn into a study of etymology, I move on. Square for our purposes is when two surfaces (usually with some substantial vertical definition and hopefully plumbed) oppose each other at exactly 90 degrees.

Simple enough, right? (It’s rhetorical.) Well, not when you live in an old house, and especially not in mine.

Props to Einstein
In my line of work (I am trying to be funny there), I get this question occasionally. “JB,” people ask, “I live in an old house. Should I be worried that the floor (in this or that location) sags a little?” My answer usually starts with a question of my own, “How much does it dip?” The answer usually is something like, “Well, I can feel it,” or “I can see it, but what do you expect; my house is 70 years old.”

That’s right, what would you expect?

At this point, I always bring up the case when I was tasked with installing a mirror above my youngest daughter’s dresser. Equipped with my screw gun, my drill bits, some hollow-wall anchors, and with a two-foot level, I went to work. I found the center point, leveled my hangers, and hung the mirror – perfectly level to, well, the earth.

I stepped back as I always do for a look. Man, it looked off, but the mirror was perfectly level. What is the problem here? Well, you see, the floor in my daughter’s room was, guess what, out of level. In the back corner of the house, it pitched downward by about a quarter of an inch or more. The floor sags there. And with a mirror -- perfectly level, hung in relation above a dresser sitting on that out of level floor, the perception was that the mirror was “out of whack.”

This really was an easy enough fix. I guess I could have propped up the dresser, but for me on this day, I instead threw my level aside and simply measured from the top of the dresser. I aligned the hangers, that’s right a full 1/4” out of level. I re-hung the mirror and I stepped back. That looked perfect.

The gravity, or is that the gravitation, of things
This effect is referred to by engineers as deflection. For a textbook definition, deflection is the degree to which a structural element is displaced under a load. In this case, with the saggy floors in our houses, this is the force applied from what is called a dead load, and a certain unrevealed weight.

Some of you reading this might say, “Oh, settlement.” Yes, settlement, that uncontrollable phenomenon that occurs pretty consistently throughout the life of a house. Most commonly, settlement, not to be confused with the expansion and contraction of wood products, manifests as cracks in wall surfaces and in doors that no longer seem to close just right. Settlement.

Settlement is the product of course of a force that we sometimes take for granted: gravity. Gravity, oversimplified, is the effect or phenomenon by which objects of mass attract each other. And as smart as we the builders are, we still have not quite figured out how to neutralize its effects. We simply plot against it, and sometimes, as is the case with my mirror from above, just have to roll with it.

PSL – Perfectly Sensible Livability
When I was doing service work for builders, I found myself saying this frequently; I was trained to do so, “That’s within tolerance.” Whose tolerance, what tolerance; I mean, I am pretty sure that there is not a section in the International Residential Building Code labeled Tolerances.

Ok, I guess what I mean here is that in construction there are certain deviations from the expected ideal of Plumb, Square, and Level that are, well, tolerable. Of course, if you slap a wall up (and again relative) on an unlevel surface, and don’t focus on plumbing (making vertical) that wall, you might be at the mercy of the center of its gravity and some lateral movement in the future. Over time, that thing in theory could fall over.

With our deflecting floors, though, what are the options? Deal with it, or not. And what does the “or not” mean? Well, I really haven’t expended that much thought on this topic, but I have to assume we are talking something like “house jacking.”

Yep, jacking the house up and addressing the issues. In cases, of course, where you cannot access framing members, this might mean the removal of wall, interior or exterior, and/or ceiling material.

In extreme cases, this of course may require the participation of a structural engineer. And structural engineers, these people are smart. And smart people usually make good money. So. . .as always, me and with my wallet, I will usually choose to live with something like that sagging floor.

Jacking it up aka remodeling
In remodeling, however, you usually get opportunities to square things up. Make them true, usually by adding to a problematic area. With an out of plumb wall, for example, this may mean adding additional studs; with a floor, this might mean installing a sleeper system (define), and so on. The point here is that it is usually a good idea to plan and budget for (what I usually write into my schedules as) “Floor Prep” and/or “Wall Prep”.

Though it usually is the most labor intensive and the most frustrating portion of any remodeling job, I just can’t skip this step. I know that so much depends on what came before, and/or what is immediately below, in front, or perpendicular to us.

And so if Einstein was a builder, his postulate might read:

PSL is relative. We, as members of all collective humanity, are really the only items that need be Plumb, Square, and Level. Take one for the team, and always, always, trust your eyeball.

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More Moxie:
I have heard that the inventor of the modern day level was the founder of this company: http://www.empirelevel.com/

For an overview on choosing and using squares: http://www.thisoldhouse.com/toh/article/0,,403568-2,00.html

One of my favorite tools -- the plumb bob: http://www.bobvila.com/HowTo_Library/The_Plumb_Bob-Hand_Tools-A2055.html