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Permit (2) c.3- HARDMAN lotto SW Nimbus Avenue,Suite B-5 GEOTECHNICAL Portland,Oregon 97223 SERVICES INC. Practical,Cost-Effective HGSlgeoteCh.tom Engineering Solutions 503.530.8076 WT. 202Z)-- (50 OE 7� s a;V(_ October 17, 2022 HGSI Project No. 21-2763 Oa ZZU Cale Doney `�Z ° t Z Sage Built Homes,LLC 1815 NW 169th Place Suite 1040 O0Z1 t I DO c-( Beaverton, OR 97006 caled@sagebuilthomesllc.com 503-969-8298 Via email with hard copies mailed on request Subject: GEOTECHNICAL REVIEW OF FOUNDATION EXCAVATION ASHBROOK VILLAS—LOTS 5-8 TIGARD,OREGON References: 1. Geotechnical Final Summary Report,Ashbrook Villas,former Address 10970 SW 95`h Ave, Tigard, Oregon; HGSI report dated May 12,2022. As requested, Hardman Geotechnical Services Inc. (HGSI) visited the site to observe surficial soil bearing conditions for the new multi-unit residential structure being constructed on Lots 5-8 of Ashbrook Villas. HGSI previously performed construction observation and testing during site development(Reference 1). HGSI personnel visited the site on October 12 and 14, 2022 to observe foundation subgrade soils. Foundation bearing soils were evaluated using a steel "T"probe. At the time of our site visit the contractor had completed the foundation excavation,to depths of about 1 to 3 feet below surrounding grades. The footing line adjacent to the Ultra Block retaining wall along the stormwater facility (north wall of Lot 8) was deepened to provide the recommended footing-to-wall setback. Soils exposed in the foundation excavation consisted of stiff to very stiff native silt, and retaining wall backfill soils along the north wall of Lot 8. The materials at prepared footing subgrade elevations are considered suitable for foundation support. Foundation subgrades as prepared are considered suitable to support an allowable bearing pressure of 2,000 psf. Estimated settlement under the allowable bearing pressure is 1 inch total, and '/z inch differential, measured over a horizontal distance of 20 feet. Care should be taken to avoid saturation or disturbance of footing subgrade soils during and after excavation. If footing bearing soils become saturated or disturbed, any softened soil or slough should be removed and replaced with crushed aggregate or additional concrete. In general, footing October 17, 2022 Project No. 21-2763 excavations should be cleaned such that no more than about 'A inch of loose soils are present prior to pouring concrete. Construction should include typical measures for controlling subsurface water beneath the building, including positive crawlspace drainage to an adequate low-point drain exiting the foundation, visqueen covering the exposed ground in the crawlspace, and crawlspace ventilation (foundation vents). The homebuyers should be informed and educated that some slow flowing water in the crawlspaces is considered normal and not necessarily detrimental to the home given these other design elements incorporated into its construction. Appropriate design professionals should be consulted regarding crawlspace ventilation, building material selection, radon and mold prevention issues, which are outside HGSI's area of expertise. We have prepared this report for Sage Built Homes, LLC and it should not be relied upon by third parties without consulting HGSI. Within the limitations of scope, schedule and budget, HGSI executed these services in accordance with generally accepted professional principles and practices in the field of geotechnical engineering at the time the report was prepared. The conclusions and interpretations presented in this report should not be construed as a warranty of the subsurface conditions. No warranty, expressed or implied, is made. O.O We appreciate this opportunity to be of service. Sincerely, HARDMAN GEOTECHNICAL SERVICES INC. �05) PROpes, .,GIN—eiNco,,,, Digitally 64422P EScottLHardman Signed I am the author of this document g OREGON 2o22.fonfsaaaamn s sFp o�� �'Q r6.2 P lTC. HPR) RENEWS: 06/30/23 Scott L. Hardman, P.E., G.E. Geotechnical Engineer 21-2763-Ashbrook Villas Lots 5-8 fnd exc rvw 2 HARDMAN GEOTECHNICAL SERVICES INC.