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ger’s technical tune-up
january 2008
part 2
Very common 1960’s
solid masonry building.
Typical header course. Given the age
of the bldg, we would assume the
backing structure is concrete block.
But, where are the header courses?
Should be every 16 inches.
Perhaps a fake header wall? No, this is a cavity wall,
so it should have weep holes and thru-wall flashing. The
subject building does NOT. A fake header wall is not common,
certainly not in 1960. See next slides for a modern example.
Here’s an example:
Old building on Church
New addition has fake
header course, but also
has weepers and vents
for PERS. See next slide.
Hard to tell from phone-pic,
But there are fake headers in
this new wall
Vents for pressure equalized rain screen
weepers
Maybe it’s a solid masonry brick and block wall with
mortar-filled cavity and brick ties, i.e. no weep holes.
These are fairly common, BUT, they DON’T have
header courses, fake or not. There would be no point.
Eg. Circa 1975 . Brick with no header courses...
…But no flashing or weep holes, either.
Here’s the inside. Block, no headers. Load bearing wall,
by the way - supports steel roof structure.
Per exterior picture, this isn’t it.
Another possibility
• Could be a wall with 3 wythes of
4-inch units, with outer brick
headered to middle (4-inch
block) only.
• If this is the case, the middle
wythe must be tied to the interior
wythe of 4-inch block with metal
ties.
• This is possible….but I doubt
that 3-wythe walls are common
for 40-50 year old industrial
buildings. Seems unnecessarily
complicated to build.
So…what is it?
Per Architectural Graphics Standards (Al’s copy, circa 1950),
we likely are looking at a Header Block wall, 12” deep.
COOL!
What Did We Learn?
• Technical
– Solid masonry walls come in a variety of styles, as
do concrete blocks
– “Header blocks” have an extra ledge that
conventional blocks don’t – no big deal
• Psychological
– Given how common this building age & style is,
have we “seen” this before but not noticed it?
– Micro inspection (for defects) can easily
overshadow Macro inspection (big picture) – don’t
forget to see the forest for the trees
– Don’t inspect on Autopilot!!
What Else Did We Learn?
• Tautological
– I haven’t observed the actual wall construction of
one of these yet, so this is an educated guess.
– But, I can tell you that I’ve seen these walls a few
times now since I first noticed it.
– If anyone has any further thoughts or
observations, let me know!
• Astronomical!
– Al’s text book is from 1950?!
– We can conclude that when Al was born, people
could be seen jumping up and down. Not for joy,
but because the earth’s crust was still pretty hot
back then.