Decking Methods 335
into a parallelogram, and the entire deck might fall. The
importance of keeping the upright members vertical is
paramount. The 1×4 uprights have enough compres-
sion strength to hold up a reasonable load, but compres-
sion assumes only a downward force. If the uprights are
allowed to tilt, failure is imminent. You can avoid this
by bracing the uprights diagonally.
The rack bracing is applied using
1
2
plywood
corner blocks similar to those used to put together stan-
dard soft-cover flats, only thicker. Glue and staple them
into place. If your load is very heavy, consider using
thicker materials or metal framing. Sometimes it works
out well to cover the entire surface of the carrier so that
it is really a hard-cover flat. This type may be used to
form its own facing material, and is great for the down-
stage side, especially if the platform is allowed to hang
over a bit.
If the carriers are reasonably short, and the size of
the decked area is large, then the carriers may be screwed
to the floor and to the undersides of the platform
framing. Do the layout by measuring the placement of
the decking area, and then setting the carriers on 4-foot
centers. The carriers on the outside edge should be flush
with the edges of the platforms. Make sure that the
interior carriers are placed where the platforms join,
and that both decks are supported. If the decking is
higher and more support is required, use triangular rack
braces.
SOUND DEADENING
Hard shoes pounding against the
3
4
plywood top of
a platform can make a most distracting noise. The
clomping and thudding of feet in a blackout remove
much of the magic of the moment. The easiest way to
deaden this type of unwanted sound is to carpet the
platforming. Unfortunately, the carpet approach is not
always feasible because of design factors. Here is a
method of deadening sound with insulation and hard-
board that works quite well and has the added bonus of
also improving the appearance of the deck. It works well
for in-house shows, but would be far too difficult to
load in for a tour show.
Use one of several different types of thin insulating
materials. Homasote works well, or perhaps extruded
foam insulation with a foil cover. Either of these loosely
compacted materials is intended to insulate a house
from cold, but it will insulate sound vibrations just as
well. Foam insulation is a bit less likely to fall apart,
and it is not as flammable or possibly toxic as the
asphalt-impregnated type of Homasote. The material
chosen should be relatively thin (about
1
2
), and should
come in 4×8 sheets. It is crucial that all of the sound-
deadening substrate be the same thickness. This method
is at its best on large areas, and it can become problem-
atic on small sections of oddly shaped decking.
Refer to the sketch of a decking layout composed
of stock 4×8 platforms. The deck measures 20-0 ×
20-0. The most straightforward method of joining the
decks together is shown. The second layout describes a
way of putting down the insulation so that the joining
cracks of the insulation do not fall in line with the joints
of the 4×8 platforms. This will prevent the telegraphing
of uneven joints upward toward the finished surface.
The final step in the process is to lay down sheets
of
1
4
hardboard to use as a paintable surface. The
finished product will appear much flatter and more
solid than just using the tops of the platforms them-
selves. The foam is too flimsy to be the top layer. You
can use a layer of just hardboard with no foam at all,
but of course that provides only minimal insulating
results, although it does greatly improve the physical

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