FNB: Opening the Windows, Part 2

Today Craig's team finished opening the brick infill and began framing the openings to receive the new windows.  It's fun to watch the folks on Main Street stop to gawk at the immense progress underway.

 
The fun part of opening the windows is seeing the change in character of the building from the outside AND inside.  The challenge is using what we find to put new windows back in.

As I mentioned in my previous post: this brick is old and it is soft.  This is also the second time is has been significantly tampered with (the first time being when they filled in the openings in the 1970s).  

Opening the windows we confirmed triple wythe brick construction = three separate brick walls that are tied together at intervals.  This type of construction is very strong at this height (two stories) - both in resisting gravity and lateral (wind) loads.  It also provides a nice, deep window sill...these walls are approximately 12" thick!

Row Lock Comparison

 
In this series you can clearly see the three wythes = face brick (exterior), integral (middle), and interior.  You can also pick out the "row lock" where the mason set a brick perpendicular to the wall to attach the integral wythe to the interior.  Don't worry, even though you don't see any row lock, the face brick is also attached to the integral wythe.  Masons of this period used a labor-intense method to attach face brick and conceal the row lock.  I've included a sketch to illustrate the different row lock methods.

A huge consideration will be the detailing to install our new large windows when that time comes.  This is the plan we prepared last week (May 29).  There are a few places where Daniel (the mason) will be making repairs but, in all, the condition of the openings is very good.

I'll be posting later on how we plan to get this done.