Joined: 25 Jun 2005
Location: River Forest, Illinois
|Posted: Sat May 13, 2006 3:47 pm Post subject: Davenport House Restoration - Connecting the Dots
|Connecting the Dots
1901 Bay Challenges
On Tuesday the carpenters return to tune the bay door openings and build the flat ceiling of the 1901 bay. Prior to a subcontractor starting a new increment of their subcontract, we are very self-disciplined about checking existing conditions, our previous work, their upcoming work, looking for potential problems, potential discrepancies, and checking quantities of new materials. When a subcontractor starts we want them to efficiently move through their work with minimal, if any, disruptions to their work flow. Disruptions induce inefficiency and expense to them or us. We want to make it easy for the subcontractors to do a quality job. We strive to address issues before they become problems or mistakes.
The new bay has presented challenges that we are now forced to address. The new bay has a nominally level floor that matches exactly the slightly sloping floor of the living room. The doors were intended to go in so that the restored doors are square and level. Final tuning of the bay including the framing for its flat ceiling is quite complicated because of the imperfect existing conditions of adjacent finishes and trim. The interior running head trim across the bay alcove has to align with the head trim on two adjacent walls which is not level. The north wall of the house has settled 3/4" lowered than the south wall. The interior trim slopes slightly to meet those points. We built the bay and jacked the floor in place such that the doors would be level and the floor would warp slightly to meet up with sloping living room floor. We thought that we had it all worked out properly.
We discovered that the door sills as we had built the bay would not align with the batten strips in the exterior siding. We did not consider that when working out the door opening. We were going to match the 1931 threshold assuming that it was the same as 1901 and we forgot about the alignment of the door sill to the batten strip. We had just assumed that they never aligned. In checking our work we concluded that we were wrong. Most, but not all window sills align with the batten strips. Further analysis of the doors showed very, very slight ghosting of the 1901 design showing that the doors butted against both the wood floor and the wood threshold. Looking at other FLW houses with a front deck off of the living room we discovered our possible error. The closest precedent to our situation was found at the Mrs. Thomas Gale House. We were going to put the doors such that they would be on top of a wood threshold which was on top of the living room wood floors. Ghosting on the doors, batten strip/door sill alignment, Mrs. Thomas Gale House and the ceiling trim detail all pointed to the following: an interior threshold on top of the wood floors which the door butted up against and did not sit on top of. The bottom of the doors would be approximately 3/4" beneath the finish floor elevation of the living room floor. This is a full 1 and 1/2" lower than what we had built. With the new approach everything just about fell in place beautifully. The batten strip and door sills would align perfectly, the doors would have the Wright sill detail.
The remaining challenge was to make up the difference between the bottom of the running head trim and level door heads. This meant that we have to make up 7/16" over 13" which is a lot and would be noticeable. We reluctantly decided the best approach would entail taking the fully restored doors that are perfectly square and shaving the top rail. Thus we would be making up 7/16" over 51" or approximately 1/8" per foot. This still may be noticeable. We will probably have the doors restored such that the top rail is 1/16" per foot out of square and shave the top of the doors by 1/16" per foot in the field. By spreading this out we should be able to hide the discrepancy so that it is not noticeable. When the carpenters arrive we will see if the carpenters can improve our approach.
Restoring the Exterior Wood siding and Trim Finish
Simultaneously we have been working with the technical lab at Cabot's Stains. They analyzed a stained Cypress board which was part of the wall above a plaster soffit that was removed was part of our structural repairs. The board had the original undisturbed 1901 stain on it. It had never been refinished or damaged by UV radiation from the sun. It also showed the relative transparency of the original 1901 exterior stain finish. We have the closeout documents from 1901 which lists Cabot
Paul Harding FAIA Owner and Restoration Architect for FLW's 1901 E. Arthur Davenport House, the First Prairie School House in Chicago | www.harding.com | LinkedIn