Floor Framing The basement has a new concrete slab-on-grade with a french drain along the exterior walls, apparently installed following the recommendations of the 1991 report to address perimeter wall leakage issues. The first, second, and attic floor systems are wood framed systems with joists spanning between bearing walls. In the basement, areas of the first-floor framing were visible and consist of 2x12 joists spaced at 12” spanning in the north-south direction. The header visible at the masonry wall openings consisted of seven 2x12 members. The framing for the other floors was not exposed, however, they most likely also span in the north-south direction and consist of similar member sizes. Overall the floor systems are in good condition; there is no sagging or displacement to indicate any structural deficiencies. Wall and Construction The structure has exterior stone bearing walls and interior multi-wythe brick bearing walls. The exterior walls have coursed rectangular ashlar units at the exterior with a rubble stone back-up at the interior. The stone is a buff-colored sandstone. The original mortar joints appear to be a soft lime-based mortar. There are several eras of repointing mortar on the building including a buff-colored mortar that appears to have similar strength to the original lime mortar as well as a grey colored mortar that has a high portland cement content and is harder than the original mortar.
Interior bearing walls on the first and second floor are wood framed but were not exposed during the site observation.
The exterior stone of the house is in overall good condition with the exception of typical weather-related deterioration (erosion) of the sandstone units in Boulder’s freeze-thaw climate. The deterioration is more pronounced at the walls near grade at the porch and entry stair. There are isolated cracks including thermal movement-related cracking of mortar joints at the porch and cracked ashlar units near the front entry door jamb. Many of the eroded mortar joints and water infiltration issues identified in the 1991 report appear to have been addressed since the report was issued. Lichen growth is present on the coping stones of the porch however it does not appear to be causing material damage of structural concern to the ashlar units. Lateral force resisting system (LFRS) The LFRS of the house consists of masonry bearing walls and wood floor and roof diaphragms. The LFRS is in good condition. It has performed well over the lifetime of the structure. Other Structural Features The site includes three stone chimneys, two on the east and one the west side of the house. The porch railing and staircase are constructed of a stone similar to that used for the building. The weather-related erosion of stone units and mortar joints in the chimneys has progressed to the point that some stones appear loose and could dislodge from the chimney.
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