Steve Brinkman Alain Pinel Realtors 167 S San Antonio Road Los Altos, CA RE: Foundation Inspection for 162 Del Monte Ave. Los Altos, CA 94022

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1 M G C O N S T R U C T O R S & E N G I N E E R S, I N C. I N S P E C T O R S E N G I N E E R S B U I L D E R S C A L I F O R N I A E N G I N E E R I N G A N D B U I L D I N G L I C E N S E A / B Steve Brinkman Alain Pinel Realtors 167 S San Antonio Road Los Altos, CA RE: Foundation Inspection for 162 Del Monte Ave. Los Altos, CA September 3 th, 2014 Based on the direction by Steve Brinkman of Alain Pinel Realtors, on Tuesday, August 26, 2014, MG Constructors & Engineers Inc. (Devorah Gomez) performed a foundation inspection to evaluate the overall condition of the existing foundation and floor diaphragm at the above-mentioned structure. Disclaimer: The professional opinions offered are based on visual observations of apparent conditions existing at the time of inspection. Latent and concealed defects and deficiencies are excluded. Destructive testing, subsurface investigation, structural calculations and seismic analysis as well as preparation of design drawings detailing any recommended repairs or improvements are beyond the scope of the services provided. An independent Geotechnical Engineer and/or geologist should be retained if a complete geotechnical investigation is desired. Owner/Agent/Buyer is granted a single use of this report for one transaction. Owner/Agent/Buyer agrees that this report is not intended for use in any legal action without written consent from MG. Page 1 of 11

2 Findings: This foundation is comprised of a cast-in-place concrete perimeter and interior spread footings and interior piers on a flat building pad, on a flat site, constructed in 1946 with subsequent additions on the north and south sides of the structure. The original and subsequent additions construction drawings, soils report and building permit were not available for review to verify the structure was done in conformance with their construction documents; however, the quality of visible construction and building materials appears to be in conformance to building code/standards at the time of original and subsequent construction, and in good, continued service with the following recommendations. All areas of the crawl space were accessible and viewed as part of this inspection. 1. Exterior Drainage. The exterior landscaping and hardscape is sufficiently sloped away from the foundation. The downspouts around the perimeter of the structure are draining directly next to the foundation (Refer photo #1). This may allow for water to collect at the foundation allowing for intrusion into the crawlspace area. This may cause settlement, mold, dry rot and cracking of the foundation and floor framing. Recommended Action: Add extensions to the downspouts to direct water away from the foundation. Photo #1, Downspout draining next to foundation Page 2 of 11

3 2. Crawl space Drainage. The crawlspace was visually inspected, the soils were dry, no corrosion was noted and there does not appear to be any interior drainage issues as of this writing. No further action required as of this writing. 3. Relative Humidity. Relative Humidity (RH), is the measured ambient quantity of water in comparison to the temperature. This measurement is important to maintain at acceptable levels (optimal readings are below 40% and acceptable ranges are between 40 to 60% R.H.) to minimize potential degradation and damage to composite structural members and ferrous metal building components. The RH was measured as follows: Crawl Space: 69.4 F. Exterior: 68.7 F. (shade), Interior: 70.9 F. The relative humidity was slightly out of tolerance; however, there was no associated damage found to the ferrous metal structural building components. Recommended Action: Monitor and maintain per items #1-4 in maintenance section. 4. Floor Frame Structure & Support Framing. The floor framing is comprised of wood floor joists supported by wood girders and wood posts on top of concrete bearing piers, at standard spacing. The following issues were noted with the floor and support framing in need of repair: (a) A floor joists was notched at the north of the crawl space (Refer to photo #2). This weakens the structural capacity of the floor joist. Recommended Action: Repair notched joist per Professional Engineer (PE) design. Photo #2, Notched floor joist Page 3 of 11

4 (b) There was a gap between the mud sill and the foundation at the north and east side of the crawl space (Refer to photo #3). It is crucial that this gap be fully grouted to allow proper transfer of forces between the floor and foundation in a lateral event, such as, an earthquake. It is also important that the wood framing fully bear on the foundation Recommended Action: Fill gap between mud sill and foundation with structural grout. Photo #3, Gap between mud sill and footing (c) There was an undermined pier at the north side of the crawlspace (Refer to Photo #4). The undermining could cause the pier to rotate in the future, which could cause damage to the floor framing in that area. Recommended Action: Fill in undermined section with structural fill to properly support pier. Page 4 of 11

5 Photo #4, Undermined pier at north of crawl space (d) There are steel floor joist hangers attached to pressure treated wood that do not have the proper coating for this type of application (Refer to photo #5). This attachment to pressure treated wood causes the hanger to corrode prematurely. Recommended Action: Install new steel floor joist hangers with the proper coating. Photo #5, Corroded steel floor joist hangers with incorrect coating Page 5 of 11

6 5. Foundation Anchorage. There are anchor bolts throughout the crawl space noted where visible. The size and spacing appears to be in conformance with building codes/requirements at the time of original construction. No further action required as of this writing. 6. Concrete Foundation. The existing concrete foundation is in overall continued service providing condition, originally formed, placed, consolidated, and installed within building code compliance and acceptable guidelines for structural concrete at the time of original construction. There were no significant areas of settlement, rotation, displacement or other deleterious issues except for the items noted below: (a) There was +/-2 vertical cracks in the foundation (Refer to photo #6). Cracks provide a pathway for water to enter, which can cause corrosion of the reinforcing steel inside the foundation wall, and frost wedging, causing separation during freezing events. Cracks at anchor bolts are a weakened condition to resist future seismic events, and are recommended to be anchored to meet minimum lateral requirements at these locations. Recommended Action: Repair the cracks per PE and American Concrete Institute (ACI) guidelines for structural concrete. Photo #6, Vertical crack in foundation Page 6 of 11

7 (b) There was an exposed piece of reinforcing steel and anchor bolt at the north of the crawlspace (Refer to Photo #7). Exposed reinforcing steel has a greater risk of oxidation (rusting). Once corroded the corrosion of the reinforcing steel typically continues over time and can travel into the foundation. Recommended Action: Properly cover exposed steel reinforcing and anchor bolt with concrete. Photo #6, Exposed reinforcing steel and anchor bolt 7. Floor Elevation. The floor elevation was measured throughout with a liquid zip level to compare the floor elevation for flatness (Reference Attachment 1). This is important to check because in some situations floors can settle, due to varying causes, usually stemming from soil settlement in parts or entirely throughout the foundation. These floor measurements showed the floor diaphragm to be within the normal, acceptable tolerances of 1 in 20. No further action required as of this writing. Page 7 of 11

8 Maintenance: It is recommended to implement a standard maintenance program as follows: 1. Keep rain gutters, downspouts and drain lines clean and directed away from foundation to lower areas in front of site. 2. Monitor foundation & Sub floor condition for changes every 2-3 years, by a qualified professional. 3. Maintain proper function of existing interior and exterior drain and plumbing lines, monitor annually for functionality. 4. Monitor crawl space annually during winter months for any signs of moisture or leaks. 5. Implement a professional pest control program per current residential standards for foundations with crawl spaces. Summary: The foundation and related floor structure were constructed within acceptable building practices at the time of construction. We recommend that the repairs be professionally engineered and installed per current building code requirements and standards. Following the repairs and other recommendations, the foundation and floor framing system will provide continued support for the structure. Maintain drainage and monitor foundation per recommendations also noted above. Sincerely, Devorah Gomez Engineer I MG Constructors & Engineers Inc. California Engineering and Building License A/B Disclaimer: This inspection report has been developed and prepared to address observations, site conditions and evaluations relating to professional construction standards at the time of construction for this type of structure. Current Building Code (2013 California Building Code/2012 International Code Counsel) has been revised from the time of original construction, and is only used as a basis of knowledge, not as a comparison. This inspection report is contingent only on what was visible at the time of inspection, and excludes any hidden, latent or other defects/situations which were undetectable to the naked eye during inspection. MGC&E Inc. assumes no liability for all unforeseen problems. This report should not be construed as a warranty of any kind, express or implied. Page 8 of 11

9 MG Constructors & Engineers, Inc Vineyard Boulevard, Suite A #232 Morgan Hill, CA Phone Fax License #A/B Job Name: 162 Del Monte Ave. Los Altos, CA Contact/Person: Steve Brinkman - APR Drawn By: Devorah Gomez Date: August 26, 2014 Scale: N.T.S. Attachment 1, Floor Elevation Survey Page 9 of 11

10 MG Constructors & Engineers, Inc Vineyard Boulevard, Suite A #232 Morgan Hill, CA Phone Fax License #A/B Job Name: 162 Del Monte Ave. Los Altos, CA Contact/Person: Steve Brinkman - APR Drawn By: Devorah Gomez Date: August 26, 2014 Scale: N.T.S. Attachment 2, Findings Page 10 of 11

11 LIMITATIONS The conclusions and recommendations stated in this report are based on a visual survey of the structure. Deficiencies which were not apparent at the time of this survey are not included in this report. This survey is limited to the foundation area. This report is designed to give a general status of the structure s foundation system. You have not requested or authorized any destructive testing, subsurface investigation, structural calculations or seismic analysis and you have not provided MG with a geotechnical report. It in no way precludes the possibility of hidden damage nor guarantees that additional damage may not occur following the survey. INITIAL ASSESSMENT REPORT ONLY This report is intended to be used for information purposes only. The information presented should not be used by others to make repair recommendations or as construction documents. The recommendations presented in this report are intended to give general direction for repairs. Complete repair detail will be specified as a part of the construction documents. AREA THIS REPORT IS LIMITED TO This report is limited to the substructure only. No investigation was made as to the structural integrity (specifically the seismic stability) of the superstructure section of the residence. LIMITATION OF LIABILITY In using this report Buyer/Owner/Agent agrees that the liability of MG, its officers, agents, employees, affiliates, parents and subsidiaries, and each of them, to all construction contractors and subcontractors used on this inspection and to the extent such liability arises from professional acts, errors and/or omissions, shall be limited in the aggregate to a sum that is no greater than the total fee of MG for services rendered on this inspection. Buyer/Owner/Agent agrees that they will require of all construction contractors and subcontractors, and will include in all contracts and subcontracts, an identical limitation of liability provision in favor of MG. Page 11 of 11