Wednesday, July 27, 2022

The Baptist Church of Streetsboro, Ohio, Part 1



This is the Old Baptist Church at Streetsboro, Ohio, built about 1820.




Here are the HABS drawings.


 I wondered about its geometry. What framing traditions had the master builder brought with him to Ohio?
It looks linear, simple, obvious. Is it?



I explored the plan and elevation. While many forms of the Lines created by circles and squares worked pretty well, nothing quite fit.  
I went back to the basics, the construction: What did the carpenter do? In what order?


He was asked to build a church about 'so big'  - here about 36' x 50'. He laid out a rectangle using the 3/4/5 Triangle.  The HABS drawings are blurry and tiny. The dimensions appear to be 38'-4.5" wide by 51' long,  3 units wide by 4 units long. (The length is about an inch too short.)

The triangles are ABC and ADC. They could also be ABD and BCD. The 2 layouts cross in the center.
The carpenter could check his diagonals, just as workers do today. When the diagonals were the same length the floor frame was square.




 The bents for the frame were naturally the same width as the floor. It seems possible that the framer used the floor of the church for his layout. I had seen this in an upstate NY barn. I wrote about it here: https://blog.greenmountaintimberframes.com/2014/12/04/geometry-in-historical-frames-a-guest-blog/

The elevation of the front of the church appears to be 2 squares wide. But the pediment did not come easily from that form - slightly too big.

However when I laid out the frame based on Lines laid on the inside edge of the sill and posts, everything fit and the peak of the bent, the location of the ridge of the church was the center of the rectangle. So simple, so easy!


How was it to the framer's advantage to lay out the frame from within the frame, not outside?  
He needed at least 3 bents, perhaps as many as 5. He needed consistent marks for lengths and widths of all members and for each mortise and tenon. The Lines laid inside the frame would not be disturbed while the frame was laid out and marked. The timbers could be moved off the floor to cut the joints; another bent could be laid out.  Or the bents could be stacked on each other.
Modern framers using timber and dimensional lumber stand within their work, measure, mark, and check from inside. Then they cut the lumber someplace else. Why not this earlier framer too?




After the bents and the roof trusses came the walls and the windows.
The spacing of the windows and their width comes from the rectangles that are within the original larger rectangle.
The green lines are 2 of those rectangles, the dashed lines with arrows on the left show the window frame locations.  The green dashed line with an arrow on the right ( top left) is the width. 



  



The geometry of the bents determined the shape of the facade, the height of the pediment. The front elements of the church - the  pilasters and a grand door -  were designed after the frame. The front windows were in place, therefore the pilasters needed to be equidistant on each side.
The door went in the middle, that's custom. Then there was the left over space in between. (See more about this below.)



The framers also had to provide support for the steeple. As I have no drawings of the side elevations, nor do I know the location of the bents. I do not know quite where the steeple sat: directly on the front wall? a few feet back?  I would assume a bent supported the front and back walls of the steeple. The diagrams do show how the width of the tower and the size of the clipped corners were determined: it was a square with its corners cut off. 

Carpenter squares began to be manufactured in the States - not imported from Britain - around 1820. They had true 90* corners and consistent dimensions. 3/4/5 triangles and rectangles were easy to lay out accurately. An inexperienced carpenter could erect a  simple frame without much worry. Or, as may have happened here, a master carpenter working with church members as a volunteer crew could expect his crew to build a reasonably accurate frame.

Part 2,  the design of the exterior of the church is here: https://www.jgrarchitect.com/2018/04/the-baptist-church-of-steetsboro-ohio.html

 

7/27/22: I wrote this post in 2018. When I reviewed it recently, I saw how much needed to be revised, simplified; how much I'd learned about using geometry in construction during the last 4 years.  Understanding Practical Geometry (the name Asher Benjamin and Peter Nicholson used) is an on-going exploration.

 



Tuesday, July 26, 2022

The Baptist Church of Streetsboro, Ohio, Part 2

The Streetsboro Baptist Church, built c. 1820: the second phase of its construction - its decoration - the front facade and the steeple.

 

 

The first post* discussed how the framer used the geometry of the 3/4/5 Triangle to layout the floor, the bents, the walls and  windows, the roof and steeple. After the framers made the building 'tight to the weather',  joiners would often be responsible for the finish work: window sash, doors, molding.  Different trades had different skills and tools.

I think this division of labor happened here.

 

The church front on a cloudy day in October. It is a handsome building. It is also a box decorated with boards and moldings. That's what I am looking at in this post.

The HABS drawing is below.





 

 

The windows had been set by the framer when he laid out the floor plan, the walls, and the roof frame. The black lines show what the front wall would have looked like when the joiner began his work. Holes for windows, a space - perhaps a larger framed opening - for a door, a triangular gable. 


The congregation expected that this box with a roof would become a modern Greek Revival church. 

Of course the joiner was considering the pediment, the frieze, the architrave. the water table. He also needed to lay out a facade which has grace and rhythm as well as symmetry.

 

Here is the geometry of the facade as the framer knew it: 3 bays with their height from the floor to the roof trusses, their width between the corner posts, and a door, centered but of undetermined dimensions. The windows are centered within the  3/4/5 rectangles of  the frame's rhythm. Their shape is 2- 3/4/5 rectangles.
 

 

I think, the joiner chooses to balance the windows first, to set them as supporting wings to the central door. The corner boards grew to become paired columns balanced by 2 more columns on the other side of the windows. Note that the columns are not on the lines of the bays, therefore the center bay is slightly wider than the side bays. The window bays became back drop to the central bay with its  double door and paneled transom.The joiner 'adjusted' the geometry; but the window bays' symmetry is so strong it is hard to catch. The tall, broad main door, recessed  in the main bay, then surrounded by the columns and the frieze, becomes the focus. 

The joiner 'fooled the eye' and created a dynamic facade, much better than 3 equal rectangles would have been.

 

The framer built the base which supported the steeple. Its dimensions at the roof are based on the 3/4/5 Triangle.


 

The steeple uses neither the geometry of the frame nor that of the front facade. It is a series of blocks, decreasing in size, with their corners clipped. The design uses the square and the circles that fit within and without it. Was it the work of the same joiner? **



The HABS drawing shows the steeple sections.

Here I have added the circles  - In 'A' the red circle is outside, the green inside. In 'B' that green circle is now outside, a new smaller red circle inside. 'C' continues the progression with the red circle from 'B' now the outside. The green circle of  'C'  is the base of the spire.

 The steeple layout follows the  drawings of James Gibbs in his book "On Architecture", published in England in 1728. Copies were in the Colonies, available to builders.  I have written about Gibbs' steeples here: https://www.jgrarchitect.com/2022/02/james-gibbs-steeples.html  

 These  HABS measurements are too simple for an in depth study of the steeple geometry.






The shapes that make up the tower are a series of blocks with related faces all derived from the simple manipulation of the square: a complete square, 2 squares, one square, half a square (the base for the spire).
The spire's height uses the width of the steeple's base as its unit of measure: it is 1.5 times as tall as the base is wide.
 

The paneling, edge moldings,  and the series of roofs as the tower extends create the steeple.







The  door itself is approximately square, the transom: half a square. They are the same size as the section of the steeple which holds the bell.



The wall of that bay acts as a setting,  a frame for the door.  The columns and architrave are a second frame.


 
   

Look again at the photographs.


The church's grace and presence come from simple proportions in the design and the understanding of how light and shadow give life to the parts themselves and thus to the whole building. 

Here is what Asher Benjamin wanted the joiner - and by extension, we who see the church - to understand about moldings :  

"...the bending, or turning inward, of the upper edge of the Grecian, or quirk ovolo, when the sun shines on the surface [and] causes a beautiful variety of light and shade, which greatly relieves it from plane surfaces, and if it is entirely in shadow, but receives a reflected light, the bending or turning inward, at the top, will cause it to contain a greater quality of shade in that place, but softened downward around the moulding to the upper edge."   ***

 

* Part 1:  https://www.jgrarchitect.com/2018/04/the-baptist-church-of-streetsboro-ohio.html

 
** The Sandown, NH, Meeting House and Gunston Hall in Virginia are good examples of this separation of craft. At Sandown a skilled joiner built the main door and the pulpit, perhaps the wainscotting and box pews. George Mason of Gunston Hall brought William Buckland from England to create the porches and interiors for his new brick house.

**Asher Benjamin, The American Builder's Companion, 6th edition, 1827, R.P. & C. Williams, Dover Publications reprint, Plate IX, Names of Mouldings.