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699 Rosa Ct - Moisture Intrusion Investigation I Encompass engineering consultants forensic analysis RECEIVED OCT 2 5 2012 April 21, 2011 Mr. & Mrs. Gehlen 699 Rosa Court Eagan, MN Re: Gehlen Residence - Moisture Intrusion Investigation 699 Rosa Court Eagan, MN Encompass, Inc. Project 11-4615 Dear Mr. & Mrs. Gehlen, At your request, a limited review of your residence located at 699 Rosa Court, in Eagan, MN has been completed. The following is a summary of our observations, analysis, and opinions based upon our review. 1.0 Introduction 1.1 The investigation consisted of a site visit to the residence by Mark Blazevic, P.E. of Encompass, Inc. on March 21, 2011. In addition to the site visit, a Certified Moisture Testing (CMT) Report dated 09/28/2010 pertaining to the residence was reviewed. 1.2 The home was reportedly built in the summer of 2003; therefore original construction of the home was governed by the 2003 Minnesota State Building code, which adopted the 2000 International Residential Code (IRC). 2.0 Observations 2.1 The home is a two-story, wood-framed, single-family structure with an attached garage and a walkout level on the rear elevation. The front elevation of the home has stucco cladding with stone accents, while the rear and side elevations are clad with vinyl siding, see photos #1-2. r Gehlen Residence 2 April 21, 2011 2.2 During our site visit, three openings in the stone/stucco on the front elevation, and two openings within the vinyl on the rear elevation were made. 2.3 The windows installed on the home consist of casement and fixed type units manufactured by Windsor Windows. 2.4 Accent bands appear around all front elevation windows. The accent bands consist of an acrylic finish installed over EPS insulation. The stucco finish was installed tight against the window frames and originally had no perimeter sealant. Based upon conversation with the owner, it is our understanding that the window perimeters on the front elevation were recently sealed in February of 2011. Cracking of the accent bands was visible at several window corners on the front elevation. 2.5 The first opening in the stone/stucco was made on the front elevation approximately 15 feet below the roof/wall intersection to the left of the main entry. 2.5.1 The removal of the stone exposed 2-layers of felt paper installed over the fiberboard sheathing. The sheathing was wet and deteriorated, see photo #3. 2.5.2 Review of the roof/wall intersection above the opening indicated that a metal diverter flashing was installed at the roof termination. The diverter consisted of a welded piece of galvanized metal. Corrosion of the metal was present along the welded seam, see photo #4. Moisture staining on the stucco immediately below the flashing was emanating from the back (innermost) corner of the diverter. 2.6 The second stone/stucco opening was made on the front elevation, main level, at the lower right corner of a double casement window to the left of the main entry. The following provides a description of the configuration observed: 2.6.1 The opening extended up the window jamb approximately 6" and across the window sill 24". The accent band, stucco brown coat, and stone sill were removed to expose the flashing configuration, see photo #5. 2.6.2 3-layers of felt paper were installed over the fiberboard sheathing; butyl tape was then installed over the top of the paper. The window was set over the top of the butyl tape. A sheet metal drip edge and a metal termination weep screed were then installed over the nail flange. 2.6.3 The weep screed flange was corroded and had visible moisture on the metal surface at the time of removal, see photo #6. The fiberboard sheathing was solid and undamaged. Gehlen Residence 3 April 21, 2011 2.6.4 Recently installed sealant was present at the window sill perimeter and jamb. The sealant had several discontinuities and voids, and covered the weep openings of the window sill frame. 2.7 The third new stone/stucco opening was made on the front elevation, upper level, below the lower left corner of a double casement window to the left of the main entry. 2.7.1 2-layers of felt paper were installed over the fiberboard sheathing; butyl tape was then installed over the top of the paper. The opening did not expose the window sill nailing flange. 2.7.2 The sheathing had a moisture content of 17% and light moisture staining, but was not damaged. 2.7.3 Moisture was visible weeping from the underside of the foam accent band immediately above the opening. Moisture was present between the layers of felt paper at fastener penetration locations. 2.7.4 Sealant was present at the window sill perimeter and jamb. The sealant had several discontinuities and voids, and covered the weep openings at the window sill frame. 2.8 Two openings within the vinyl siding were made on the rear elevation, the first was located on the lower level at the window head of a double casement window, while the second was located at a window head of a single casement window on the main level at the deck. Both openings exposed the flashing configuration at the window head. Butyl tape was adhered to the fiberboard sheathing then extended down onto the window nail flange. At the first opening, a 12" long section of the tape was missing. At both openings, the butyl was poorly adhered to the sheathing and was pulling loose, see photos 7 & 8. 2.9 The owner reported interior moisture leaks at 8 window heads throughout the home. All but one of the windows were located within vinyl sided areas. Visible moisture staining was present on the frames at the heads of most of these units. The window within the stucco was the unit located immediately below stucco opening #3 on the front elevation. 2.10 A review of the CMT moisture test report from 9/28/2010 indicated several areas of elevated moisture. These areas included the main and upper level windows to the left of the main entry on the front elevation, and a roof/wall intersection to the left of the entry on the front elevation. These areas had moisture contents ranging between 17 and 23%. No other locations of elevated moisture content were noted. Gehlen Residence 4 April 21, 2011 2.11 Moisture intrusion into a lower level mechanical room was reported. Review of the foundation wall identified two locations of moisture entry. At these locations moisture was present on the exterior side of the vapor barrier. The first location corresponded with a vertical crack in the wall near a corner/jog in the wall. A second location was at a corroded steel form tie which penetrates wall. 3.0 Analysis/Conclusions 3.1 Based upon a review of the exterior facade and invasive openings, moisture intrusion and/or localized deterioration of building components has occurred. The deterioration is limited to the following locations: 3.1.1 Front elevation: Roof/wall termination to the left of the main entry extending the full wall height behind stucco and stone; corroded metal flashing below main level window to the left of the entry; Accent band on upper level to the left of the entry. 3.1.2 Right, Rear, and Left elevations: Debonding of head flashings at windows within the vinyl siding. 3.1.3 Foundation wall: cracked foundation wall and corroded form tie allowing moisture into the lower level mechanical room. 3.2 The window flashing as viewed at one location on the front elevation (stone or stucco) consisted of the following: 3.2.1 Two-layers of felt paper and one-layer of butyl tape installed behind the window sill nail flange. This sill flashing configuration is in general building code compliance and is consistent with industry standards. 3.3 The absence of sealant allows moisture past the stucco and onto the weather barrier resulting in corrosion of metal flashings and elevated moisture readings below windows. The moisture entering through the unsealed perimeter has also likely migrated through fastener holes in the weather barrier between the upper and main level windows on the front elevation resulting in the observed interior window head staining. This observation is consistent with the 17% sheathing moisture content reading taken at opening #3. 3.4 The absence of window perimeter sealant as part of original construction also allows moisture into the foam accent bands exacerbating the observed cracking. 3.5 The diverter flashing installed at the left side of the main entry is allowing moisture to bypass the flashing and subsequently migrate behind the weather barrier. The Gehlen Residence 5 April 21, 2011 resulting moisture intrusion has migrated down the sheathing surface extending down into the stone veneer approximately 15 feet below. 3.6 Staining of interior window frames and trim at the heads of 8 windows was observed. Subsequent removal of siding above two of these windows identified discontinuous and/or debonded adhered flashing installed above window head nail flanges. Moisture draining down the exterior face of wall sheathing is directed behind the flashing and onto the window heads where this flashing deficiency is present. The discontinuity and debonding of head flashings are the result of a poor and/or deficient installation during original construction. Based upon the large quantity of interior window head leaks, it is our opinion that this condition exists at all windows and doors within the vinyl siding. 3.7 The moisture intrusion observed through the front elevation foundation wall is the result of the following conditions: corroded steel form tie which extends through the foundation wall, and a foundation wall crack adjacent to the main entry. The form tie creates a discontinuity in the exterior damp-proofing allowing a path for moisture entry. This observation is consistent with water entry/staining observed around the tie, and not from any area above. The wall crack is likely the result of concrete shrinkage. The damp-proofing is unable to bridge the crack, and as such creates a path for moisture entry. 4.0 Recommendations 4.1 In order to repair the existing damage and prevent future damage, the following repairs are recommended. 4.2 Front elevation: Remove stucco extending from roof-wall intersection at left side of entry down to base of wall. The removal should extend laterally to the left corner of the home. Replace damaged building components including sheathing and flashings. Inspect windows for damage, and repair or replace as necessary. Re-establish weather barrier and install new stucco and stone. Replace diverter flashing. At the right side of the main entry the accent bands should be removed and replaced with an alternative trim material. The new trim should be installed with a %z" space for sealant between the trim and the window frame. 4.3 Right, Left, & Rear Elevations: Remove vinyl siding at all window and door heads to expose existing flashings. Install new adhered flashing over existing and missing areas, and adhere to sheathing above existing flashing. Install termination bar and sealant along top edge of new flashing. Reinstall siding. 4.4 Front Elevation Foundation Wall: The front wall should be excavated extending down to the leaking form tie. The damp-proofing should be repaired to prevent Gehlen Residence 6 April 21, 2011 further leaking. The shrinkage crack should be epoxy injected along the entire length of the crack. 4.5 Install perimeter sealant at all window, door, mechanical, and electrical penetrations throughout the home. Remove sealant from head flashings at windows/doors (if present). This report is prepared based on observations and review of the limited quantity of material available as of this date. Our opinions may be revised based on the availability of additional data. The conclusions contained herein represent our professional opinions. These opinions were arrived in accordance with accepted engineering practices at this time and location. No other warranty is implied or intended. Respectfully submitted, ENCOMPASS, INC. Prepared by: Mark Blazevic, P.E. Project Engineer 15A.- ~3Y~Yir II Gehlen Residence 7 April 21, 2011 i man liggil; Photograph #1- Front Elevation A:K Photograph #2 - Rear Elevation Gehlen Residence 8 April 21, 2011 i. aI.h 1/ ,',fit Photograph #3 - Stone Opening #1 f Photograph #4 - Kickout above opening #1 Gehlen Residence 9 April 21, 2011 4Iy i 1.f. Photograph #5 - Stucco/Stone Opening #2 tt i Photograph #6 - Stucco/Stone Opening #2 Gehlen Residence 10 April 21, 2011 M .Y., q f Photograph #7 - Vinyl Opening #1 i, i 4 IJ r ~11~ r' I r-' Photograph #8 - Vinyl Opening #2