The URL can be used to link to this page

Home My WebLink About1985-10-19 Construction Soil ConditionsI 1 I I } /' r\M -1)^ f*'v/ vi SOIL exPiORation com»*ar»w» 3908 COMMERCE COURT SW ROCHESTER, MN 55901 PHONE 507/280-7060 a sislef cofpoiation to TWIN CITY TESTING AND ENGINEERING LABORATORY INC October 19, 1984 / r e-3 'j l~^^ Mr, John Lanier 3060 Fox Road Long Lake, Minnesota 55356 l^\' MW 20 085 rfiV (5i-Tiui.iiT ' SUBJ: Report of Site and Subsurface Observations Re^idence..3Q6Q Tong Lake, Minnesota JOB #120-12767 Dear Mr. Lanier: OFFICERS: CHARLES W. BRITZIUS chairman of the board NORMAN E. HENNING president ROBERT F. WITTMAN executive vice president CLINTON R. EUE secretary/treasurer INTRODUCTION HOME OFFICE: ST. PAUL, MN You are presently remodeling your house and would like to add a second-story area over the existing westerly addition on your house. The building inspector has indicated to you that the footings along the outside perimeter of the house are not at frost depth and should be extended to frost depth if you wish to make the addition. We were asked to observe the foundation condition and give our opinions with respect to providing frost protection of these footings. OFFICES IN: MANKATO. MN ROCHESTER. MN SITE CONDITIONS We visited the site on Wednesday, October 17, 1984 and observed the condition of the foundation wall both on the exterior and on the interior. A sample of the bearing soils was obtained during our visit. The bearing soils are a sandy lean clay with a little gravel and grayish brown in color. These soils are most likely glacial till in origin. The existing wall footing is approximately 2' below the outside grade and supports a concrete block wall on which wood floor joists bear.The joists span from the west wall of the present addition to the west wall of the original house approximately 12' to the east. AS A mutual protection to clients t ie public and ourselves all retorts are submitted as the CONE'IDENTIAL PROPERTv of the client AN equal opportunity employer Mr. John Lanier October 19, 1984 Page 2 There is no evidence of settlement of the existing foundation nor any problems related to frost. The existing siding was placed on the house at least 17 years ago and if this type of problem existed the siding should be buckling or separating at the juncture with the original house. The heat in the crawl space underneath the present addition prevents the soils at the exterior wall from freezing due to circulation of warm inside air. CONCLUSION In our opinion, there has been no problem with the existing footings due to frost penetration. As long as the crawl space Is left open to the heated area of the basement, we do not foresee any frost problems with respect to the present footings. In our opinion, from a soils standpoint. It would not be necessary to extend the footings to frost depth at this time. RECOMMENDATIONS To conserve energy we recommend that Insulation be installed on the exterior of the foundation wall. The insulation should also extend beyond the edge of the footing approximately 2’ to minimize heat loss from the present structure. This should also minimize the possibility of frost penetrating below the existing footings. The Insulation selected should not absorb water. Insulation should not be put on the inside face of the wall since this could shield the foundation soils from the heat source which has prevented them from freezing in the past. Insulation could be placed at the top of the block wall between the floor Joists to prevent heat loss in this area of the crawl space. We recommend that where concentrated loads will be carried down through your present structure from the proposed addition, at least 3* by 3' concrete pads which are a minimum of 12** in thickness should be cast below the present footing level. These pads should be a minimum of 42" below the present grade which will result in pads approximately 18" In thickness. We i J j i Mr. John Lanier October 19, 1984 Page 3 reconvnend reinforcing the bottom of the pads with four #5 bars in each direction. Reinforcing bars should have a minimum of 3'* of concrete placed under them and extend to within 3” of the face of the footing pads. In our opinion, the subgrade soils are capable of supporting a foundation load for spread footings of 2000 pounds per square foot. Very truly yours. Richard S. Dutcher, P.E. Senior Project Engineer This report was reviewed by: Wil A I hereby certify that this plan, specifi- cation, or report was prepiired by me or urtder my direc t supervision and that I am a duly Registered Ptotess-onal Engineer th^laws ^ th^T^of Minnesota Date I O" I'^-^^RePKtratinn No. 8656 thereby eerfify ihof thU pJoiv fpecHIcaticL or report wot proporMf by mo or under my dfract * ®"’ ** "•9*5*erad *«'•' thelowtofih, ofolo of Minnesota lil. Dote aMjJL a. f.yf 0 wOfred a. WAHlUfRED a. WAHl i£jL[Llll_Reo. No. 6V Proofread by: