Monday, August 25, 2014
Buildings
move, always have and always will. They expand and contract so control joints
must be employed. Wood expands when it gets wet and contracts when it dries.
Wood is always accepting or getting rid of moisture and no amount of nailing,
gluing, or screwing will keep wood from moving.
Masonry
swells when it gets wet and shrinks when it dries.
Concrete
is the most universal of all structural materials employed. Concrete cracks,
moves, shrinks, and sometimes “curls”. Concrete always has and always will
crack. Doesn’t matter if it’s reinforced or not. The use of control joints via
saw cutting or mechanical design can direct the cracks into a straight line and
make them more aesthetic. Cracks do not necessarily mean the concrete is weak.
Control
joints should be designed in concert with your water management system because
your building, in practical terms, cannot be penetration free.
Normally
water will follow the path of least resistance. Provide an easy path for water
to travel and let it follow that path away from your building envelope.
