HISTORIC REVIEW / ANALYSIS OF WINDOWS, INTERIOR WOODWORK and FINISHES

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1 Tuesday, July 14, 2009 Bloom Companies Eric Hampshire W. Research Drive, Suite 100 Milwaukee, WI RE: University of Wisconsin / Milwaukee Greene Museum ca N Downer Ave Milwaukee, WI HISTORIC REVIEW / ANALYSIS OF WINDOWS, INTERIOR WOODWORK and FINISHES WOOD WINDOWS Upon review, we found completely intact, original windows throughout the Greene Museum Building. Following is an analysis by category of the condition and pertinent information with regard to the windows. Their overall condition relative to comparable projects from the same time period is outstanding. Relatively little has been done to modify the original openings, except modification of some interior mouldings in the lower level. Sash The window sash are structurally sound with minor deterioration. Exteriors show minor checking and UV damage typical for the age of these windows. Had these windows been fabricated 20 years later, they would have been made of new growth lumber and consequently, the damage sustained would have been substantially increased. Based on the period of construction, current condition, and our observation of as many as 16 growth rings/inch, it is reasonable to assert that these windows are fabricated of old growth or virgin lumber. Old Growth or virgin lumber refers to lumber that stood for over 100 years and may date as far back to pre-revolutionary time. Because of its significantly higher density, along with numerous other factors, old growth lumber has tremendously better structural and dimensional stability and rot resistance. The cutting of this lumber, because of its scarcity was finally halted in the early 20 th century shortly after the time of this buildings construction. Species of sash is W. Pine. The sash are built using half blind mortise and tenon on the bottom and top rails and mortise and tenon joints at the checkrails. Muntins are 1 wide, which would not be durable using new growth wood. Frame The frames, having been mortared in per the period practice are still square and tight. The window sills in particular are a testament to the quality of workmanship and materials available during the period. They are a full 2-1/2 thick clear material set at a 14 degree pitch as opposed to the standard 7 degrees on some windows. They were built to perform for centuries on windows, not to best suit mass manufacturing. The massive sill no doubt extends to the outside panel of the weight pocket and is effectively integral with the brick on the building. Interior Window Trim Interior mouldings are believed to be original and based on species analysis as shown following, it is believed to be Birch. The mouldings in and of themselves are typical for the period. What is notable is the craftsmanship with which they

2 were installed. The stool is coped on each side to give the look of a mitered return stool. Coping in this manner makes for the strongest, longest lasting stool as well as the most aesthetically pleasing. On a side note, the door casing in the building illustrates similar almost-lost craftsmanship and techniques in their fit and joinery. Glass and Glazing The glass in this project was very exciting to find. At first glance, we thought it was Fourcault style machine drawn glass, but it is even more rare. The glass on this project is machine drawn cylinder glass, which was invented in 1903 in the US. This was the first mechanical method of drawing glass. The process was to draw large cylinders of glass vertically from a circular tank, anneal and then cut them to 2 to 3 meters before reheating, cutting and flattening. It was one of the first American improvements to the flat glass industry, which found its ingenuity primarily in France, England and Germany. It has a unique striation pattern all its own and may have had the shortest life of any glass manufacturing process. By the time the nation retooled, Emile Fourcalt had designed the flat drawn glass method in Belgium in 1913, which replaced the cylindrical manufacturing method in use for over 100 years in the UK in 1919 and shortly thereafter in the US. The value of the glass in these windows today is between $30 and $50 per square foot. Flat drawn sheet glass similar to the Fourcalt process was gradually improved upon by methods such as the Pennvernon process in 1925 until 1959, when Pilkington introduced the float glass method, which is how almost all window glass is made today. The glazing compound, however, is deteriorated and all glazing compound should be carefully removed saving the original glass, and the glass reset in a new bed of glazing compound. Finishes The interior and exterior finishes on the windows are well deteriorated and need to be completely stripped and refinished. The interior stain color is believed to be original. We removed samples of the paint to examine the layers on the exterior of the windows and sills. See paint analysis report attached. Weatherstripping / Energy efficiency There is currently no weatherstripping on the windows. With restoration, air infiltration should be minimal, but it should be noted that windows were originally manufactured with wood storm windows in mind and may have even had them upon original installation. The brickmould on the exterior shows signs of original storm hardware and has a perfect 1-1/8 flat where a wood storm window would be installed. Restored with a proper storm window, tests show that the window will outperform a new insulated glass window s energy efficiency. Hardware Almost all original hardware is still in place. Several sash lifts are bent from abuse. Most likely the windows were painted shut and one point and excess pressure was applied in an unsuccessful attempt to open the window. All hardware looks to be solid brass and could be bent back in to shape and cleaned and polished if desired. Pulleys are existing and operational.

3 Recommendations Because of the unique and irreplaceable qualities of the glass and old growth wood, which the windows are made of, as well as the relative excellent condition they are in, we recommend that they be restored to original condition. We believe the windows were originally intended for wood storm windows on the exterior and new storms should be considered. We recommend wood storms vs. the more common aluminum storms due to the existing windows apparent intention for wood storms as well as the better thermal properties wood storms would provide. STEEL WINDOWS We encountered steel windows in one room of the building. Based on our inquiries, there was an adjacent building that required the installation of fire resistant windows on this area of the building. It is not widely known that wire glass was first made in 1898 as 'Hexagonal Rolled wired cast' introduced by Pilkington. The jambs of these windows are steel as well as the sash. The interior may well have had a faux bois finish to match the stained windows in other areas. Based on examination of the manufacturers plate riveted to the bottom of one of the sash, we believe these windows may also have a bit of local Wisconsin history to them as well. It is unclear the level of difficulty in removing these as they may be anchored with mortar to the masonry. The steel windows present a unique situation. We believe they are original, but they are not nearly as significant to this building as they are to the fact that another building stood adjacent to it. An interesting item to note: We have another client in Lansing, Michigan performing a $16 million restoration project, who we are meticulously removing and salvaging this exact type of glass for on their project. While some may consider it inconvenient, or even an eyesore, it has a great deal of historic significance and is a sought after historic architectural detail. INTERIOR MOULDINGS All door, window and base mouldings on the interior appear to be original. Typical for the period, the base is a combination of 3 mouldings, a plain base, a cap and a shoe. The base is the same throughout and the profile is included in our drawings. The door and window mouldings are also drawn and are matching throughout the building. There are two different handrails on the staircase. One is made of birch, has highly decorative bronze brackets and measures 3-1/4 x 3-1/4. It has curved volutes to join the next section as it turns the stairs. We ve determined this to be an original. A later addition hangs on the wall across from this handrail and is made of pine with different measurements, smaller dimensions and nondescript brass plated brackets. Respectfully Submitted, History Wood and Window Paul C. Birkett President

4 Wood analysis Interior Trim and Mouldings Gross features Growth rings indistinct Diffuse porous Macroscopic identification Somewhat uniform rays, smaller than the largest pores. Microscopic observations Tri-seriate rays, no spiral thickenings on cell walls, extremely small intervessel pitting. In the group of diffuse porous hardwoods, the following possibilities were explored: Beech, Sycamore, Cherry, Maples, American Hornbeam, Red Alder, Poplar, Basswood, Holly, Dogwood, Magnolia, Hophornbeam, California Laurel, Willow, Cottonwood, Aspen, Buckeye, Horsechestnut, Sweetgum and black Tupelo. Each was systematically ruled out for various reasons including: This specimen displays larger pores than rays. Specimen also displays no nodes on rays at growth ring boundaries. Specimen does not contain aggregrate rays. Specimen does not contain spiral thickenings on the vessel walls. Based on the sclariform perforation plates between vessels as documented in photo 1 and extremely small intervessel pitting, we believe the wood to be Birch Evidence of scalariform perforation plates Photo 1 Radial section (400x) Tri-seriate rays Photo 2 Tangential section (400x) Transverse Section showing diffuse porous and fairly indistinct growth rings. Photo 3 Transverse macro (30x)

5 Wood analysis Window Sash Gross features Indistinguishable from staining and finishing Macroscopic identification Appearance of large resin canals and apparent softwood structure Microscopic observations Abundant, large resin canals, fusiform rays present In the softwoods, the following possibilities were explored: Pine, Douglas Fir, Spruce and Larch Each was systematically ruled out for various reasons including: Size and quantity of resin canals, color and density of wood under magnification. Based on observation, the wood in the window sash is White Pine. Several species could be used although Pinus Strobus was most popular. Growth ring with distinct coloration Photo 1 (40x)