I learned something interesting regarding the roof and the settling of a house.  In some cases, the roofing material can be so heavy, it can cause the house to settle.  This is common with the Spanish style roofs we have in Santa Barbara, as the material is pretty heavy.

The problem is, if the roof tiles are put on after the windows are put in, or the siding is put on, or the inside walls are plastered, the settling of the house can cause problems as things will shift.  Oh, you thought your house was always perfectly square and never moved.  🙂

In fact, settling is probably more common than you think.  The temporary rental we are in until our house is complete developed a plumbing leak because of settling.  The depletion of the ground water due to our extended drought in California caused the ground to settle.  The house is on a slab, and the plumbing goes into the slab.  Tension between the pipe at the slab and the pipe attached to the framing on the second floor caused the pipe to snap inside the wall.

In our case, it is important to consider whether the load on the roof might cause the house to settle.  If so, it would be important to load the roof first.  Typically, they will simply put the roofing material on the roof in stacks, distributed evenly around the roof.  This is what it looks like:

I’ve often driven by the a construction site day after day and see the roof tiles in piles like this.  I always assumed that the project was stalled for some reason, but, as it turns out, they had just loaded the roof so the house would settle properly.

In our case, we don’t need to load the roof as we are using asphalt shingles.  Asphalt shingles weigh about 2 lbs per square foot, compared to concrete roof tiles at 12 lbs per square foot, and Spanish style clay tiles, which come in at a whopping 19 lbs per square foot.  In other words, our roof won’t have that much load, especially as compared to the weight of all the wood and concrete underneath it.  Yea, all this:

For a roof our size (about 2500 square feet) that is the difference between a roof weighing about 5,000 lbs, and one weighing almost 50,000 lbs.

Incidentally, did you know that a typical three story house (which ours is as it has a basement) weighs 350 lbs per square foot, not including the concrete?