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, • The exterior cracking was consistent with normal levels of distress observed in other structures of similar age and construction. As wood-frame structures age, the wood and building components are subjected to repeated cycles of extension and contraction cause by seasonal variations in temperature, and to minor differential settlement resulting from soil densification. Because of the different rates of thermal extension and contraction of the materials, this results in hairline to minor cracks forming at stress points in the structures, primarily at window, door, and wall corners and along joints. The cracking is not structurally significant and does not reflect significant movement of the structure. • The limited cracking in the interior drywall sections is related to moisture and temperature fluctuations in the enclosed spaces of the walls and attic. Separation of corner bead and minor cracks in complex sections (such as the doorway arch in the hallway) are common. These are not considered a settlement related issue. • The delaminating tiles are related to poor bonding between the tiles and underlying concrete substrate. This condition is generally attributed to poor adhesion of the tile mortar used to set the tiles. This condition is not related to settlement of the foundation or floor slab. Overall, the current level of settlement distress to the house is minor. Ho�vever, remedial measures to stabilize the structure against further sinkhole related settlement should be implemented. These should include a program of compaction grouting to address the subsurface zones of loose and apparently raveled soils underlying the structure. Since the grouting will likely not be fully effective in stabilizing the shallow loose sands directly below the foundation, a program of shallow chemical grouting is also recommended. The floor elevation survey and limited cracking distress indicate the house has not been subject to significant differential settlement. Given these conditions, foundation underpinning and interior chemical grouting to re- level the structure is not necessary. We also recommend that rain gutters with downspouts that discharge rainwater a minimum of 5 feet from the foundation be installed on all roof drip edges. A remediation plan is included with this report. 4.0 REMEDIAL MEASURES 4.1 Compaction Grouting A program of subsurface compaction grouting is recommended to stabilize the subject building against further sinkhole or karst-related settlement. The intent of the grouting is to stabilize the raveled and very soft soil zones that may underlie the building and to seal and fill the karst- related fractures and/or cavities in the underlying limestone bedrock surface. The recommended grouting program should consist of a series of vertical and angled grout injection points around the perimeter of the building. A low slump grout (3 to 5 inches) should be utilized to ensure effective treatment of the loose soil zone(s) and reduce migration of grout beyond the affected areas. F �;��s=ae��c� ;nv°estigatia�-, �C1 1',•oj��ct�Jo. 0�-l f�6 i� C}�a��e l�i�ss;��r� R�r,c�lz l�sso��iat�o�� (nc��orate� fi��il 20?0 C1ai�:: 1�i._,. ;�t}„:�:��C� �t,`�e c,•