I'm quite sure that's a correct statement. However, it is also possible
to have very light truss construction with great strength. It's done
with what's called the Simpson Strong Tie system. This page shows just
the truss to top plate connector
<https://www.strongtie.com/products/lateral-systems/strong-rod-systems/urs/components/truss-to-top-plate-restraint>
There are many other kinds of connectors in the system which, when
used all together, tie the roof to the walls and the walls to the
foundation or floor slab. In a hurricane it's imperative to keep the
roof from lifting off or the entire structure will be destroyed.
My (newly built) South Carolina house uses Simpson Strong Ties
throughout. It has 2x4 construction in the trusses and 2x4 and 2x6
construction in the walls. It also has massive steel connectors between
the 2x6s and large diameter bolts embedded in the floor slab. This is
all supposed to hold the house together through a category 3 hurricane.
The house has asphalt tile.
My Florida house used the same type of 2x4 construction methods in the
roof trusses but was tied to the floor slab with bolts and rebar into
concrete pillars spaced every 8 feet around the periphery. That house
had concrete roof tiles (about 1" thick) and survived about an hour of
120 mph winds during hurricane Andrew in 1992.
<https://en.wikipedia.org/wiki/Hurricane_Andrew> I also had the doors
and windows protected with hurricane panels. The house sustained no
damage at all except the loss of some screening in the swimming pool
enclosure. But it did take a long time to clean all the dirt and debris
out of the pool.
Simpson Strong Ties are also used in earthquake prone areas. Their
major labs are in Stockton and Pleasanton, California. South Carolina
is also an earthquake prone area. The Charleston earthquake of 1886 was
the largest earthquake ever to hit the east coast (Mag. 7.3).
Chuck Norcutt
On 3/8/2016 11:53 PM, Moose wrote:
The vast majority of home construction in the US is focused on minimum
cost. Some of it may look fancy, but underneath, even most of that is
CHEAP.
Asphalt shingle is inexpensive to buy and to install. It's also light,
so the roof structure can be light and cheap, too. And it doesn't
require much pitch, again requiring fewer materials. It lasts somewhere
over a decade; most importantly lasting longer than any home warranty.
You can be sure that the weight/grade for new construction is carefully
chosen with that in mind.
Then the light roof structure tends to dictate what replacement can be
done when it wears out. My roof is supported by 2x4s on 24" centers.
When it needed replacement, I found that none of the cement, tile or
slate alternatives could be used without expensive reinforcement of the
roof. I ended up with a metal roof that looks vaguely like shake, is
very light and lasts many years. It's proven so far to be an excellent
choice.
--
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