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Bar B C Data Analysis

Reading the Roof Data
Structural defects were studied first and the results suggest that the condition of the walls was significantly related to the condition of the roofs, i.e. a building with a low score for roof condition often had walls that also scored low for condition. Although this would seem to be obvious, the collected data actually supported and expanded the assumption.

Structures with roofs in good condition had walls in good condition and vise versa. The analysis however, did not show any significant relationships between walls and foundations or foundations and roofs.
The two recorded environmental variables that had the highest correlation were roof orientation and the presence of trees within twenty feet. Orientation directly impacts the amount of sun and shade that a roof endures and trees add litter to roofs which can retain moisture and create adverse conditions that speed deterioration of the roll roofing as well as suffocate the vegetation on sod roofs and possibly change PH levels. Obviously roofs protect the walls and interiors from exposure to the environment, but they are topped with sacrificial materials such as rolled asphalt that is known to decompose due to UV radiation and moisture.
Reading the Wall Data
Although many of the walls throughout the site exhibited signs of damage, overall surface condition was good; however, the structural condition of the walls did not perform as well and affected the integrity of the walls as load bearing components.

These adverse structural conditions were identified as:

  • Tilting
  • Racking
  • Displacement
  • Deformation

Wall corners, purlins and sill logs were obviously identified as focal points to understanding what environmental factors were causing damage. An average of tilting, racking, displacement, and deformation scores helped provide analysis of the sill logs and structural conditions within the walls. The presence of mechanical deterioration was often indicated by a damaged sill log, but damaged sill logs were not good indicators of mechanical deterioration. Also, not all four of the mechanical deterioration types were associated with sill condition. The presence of deformation and tilting often directly involved a sill log in poor condition, whereas racking and displacement often did not.

The relationship between purlin condition and the structural condition of the walls did not provide a good indicator of condition, although further analysis of these 2 factors in relation to each wall corner type may demonstrate higher correlations. For example, box and post log cabins may have worse structural wall damage and deteriorated purlins, as opposed to more secure corner types like square notch and saddle joined structures. The analysis between corner type and structural wall condition showed a strong relationship between tilting, racking and deformation, however displacement was not a good indicator of corner condition.
tilted wall
An example of severe "tilting".
Bad roof
This roof lost its asphalt and was temporarily protected with a tarp.
bad chinking
Lower log decay from snow contact and UV exposure has resulted in complete replacement.