Limited Leak Assessment

Transcription

1 Website: December 2th, 2005 Limited Leak Assessment Property Address US Naval Facility Building 484 Panama City Beach, Florida Report Ordered By: Doug Ashley of Bullock - Tice Associates 5974 West Shore DrivePensacola, Florida (TOLL FREE) (LOCAL) (FAX)

2 INTRODUCTION Limited Leak Evaluation & Assessment At the request of Doug Ashley of Bullock-Tice Associates, Moisture Consultants, Inc. performed a Limited Leak Evaluation and Assessment at the Naval BEQ Building 484 located at Panama City Beach, Florida. The services were limited to a 1 day effort including travel resulting in approximately 8 total manhours on site on December 2, OVERVIEW Upon our arrival a basic overview / tour of a typical leak area was given by building & maintenance personnel. The leak areas addressed in this evaluation involve 4 corner sections of the building which all share unique design features different from the typical exterior walls of the majority of the building. The leaks reportedly show up primarily as wet carpet, wet walls, ceiling tiles and leaking windows leading to ongoing damage to window sills, sheetrock & carpet and some reported past mold & mildew growth on walls. The leakage has been ongoing for several years with several attempts made at repairs with varying results and reduction of leakage but no efforts have been completely successful. The building managers office had several areas of sheetrock removed exposing the wall cavity apparently for previous leak evaluation and for pending interior repairs. The exposed wall cavity show evidence of extensive leakage with significant damage to some of the metal stud framing. Some of the leak areas have undergone extensive interior repairs including removal of all sheetrock, extensive repairs to damaged studs, reinstallation & finish of sheetrock, trim and replacement of window sills and carpeting. The exterior repair efforts reportedly may include sealing of the brick (several times), various sealant work, some roof repairs and even the removal of some brick and rework of of some of the through wall flashings. METHODS Limited leak evaluation methods included brief interviews with personnel, visual inspection, random moisture scans and hydrodynamic testing. Scans were performed using a Tramex Moisture Encounter meter. Hydrodynamic testing was performed using a test wand with a calibrated Monarch nozzle. We utilize our own test methods which we have found to be helpful in duplicating reported leakage. Some of our testing 'exaggerates' water intrusion to evaluate the performance of building envelope components. Photographic documentation and hydrodynamic test result can be found after the Executive Summary pages. 1

3 EXECUTIVE SUMMARY Based on visual observations and limited hydrodynamic testing we believe the following to be the most probable causes of the reported leakage shown in order of severity. Each will be discussed individually. Photos of various details are on the pages following with possible water intrusion risks / paths shown in blue. 1. Failure / Inadequate Moisture Barrier System (cause of greatest volume of leakage) 2. Failure / Inadequate Termination of Roof flashings at brick walls 3. Leakage at coping seams (contributing to item 1) 4. Failure of Pan Flashings Under Windows 5. Leakage at vent units (contributing to item 1) MOISTURE BARRIER SYSTEM Based on the areas exposed for inspection and testing the Moisture Barrier System is not adequately returning waterflow behind the brick back to the surface. Photo 4 shows that the moisture barrier system ends abruptly at the stone trim work at the windows creating a great risk and weakness. The through wall flashings do not appear to have proper end dams and in some areas 'sag' creating a cavity that is 'lower' than the weep exists. Photo 4 also shows an attempt to create an end dam by sealing the thru wall to the stone with roof cement which is not adequate and leaked during testing. Test 2 showed water standing up to 3 inches in the thru wall flashing and readily caused steady leaking below. The greatest leakage during testing was test 4 which was an exaggerated test of water intrusion into the wall cavity through the weep holes directly above the windows (Page 18 photos). The entire wall area experienced considerable leakage inside including soaking the carpet, leakage at the windows and leakage down the interior side of the sheathing. Water could be heard 'pouring' into the window framing which then leaked out at seams (photo 31). The wall cavity above the window was not visible for inspection to determine specific detailing methods. We also noted that the through wall flashing in the test area is attached on the surface of the felt barrier not properly lapped under the felt barrier. The horizontal 'edge' where the felt and thru wall meet was 'buttered' with roof cement. Any deficiency at this juncture would also cause leakage into the wall cavity. Based on the above observations we feel it would be impractical to successfully remediate the existing moisture barrier. Any attempt to remediate it would require the removal of the brick system. Because of this we feel the most practical long-term solution would be to install an EIFS cladding over the brick cladding. An alternative may be to attempt to transform the brick into a complete barrier system getting rid of all weeps, gaps etc. and possible application of coating systems. The challenge in this opt ion would be the compatibility of the existing brick sealers with any coating system. Either solution should explore the effect on the dew point to insure a new thermal problem is not created. See suggested scope of work for EIFS cladding suggestions. 2

4 EXECUTIVE SUMMARY (cont.) ROOF FLASHINGS AT BRICK The dormers over the vents create valleys and transitions / terminations of the roof system at the exterior wall (see photos 6, 7-10). Some of the visual leakage evidence and moisture scans were directly below such a termination (photo 9). These transitions could be easily sealed / modified as needed to prevent water intrusion through the transition details. Repairs should include checking for proper lap and seal of pieces at valleys, proper lap and seals at sidewall details and proper seal of flashings to dissimilar materials. LEAKING COPING SEAMS While the coping seams were not tested for leakage we feel that they may be a contributing factor to waterflow into the failed moisture barrier system. There was a few areas of coping that appeared to have an underlying secondary 'peel n seal' barrier under the coping. There were also areas checked that do not appear to have any secondary peel n seal moisture barrier under the coping. Without a secondary barrier it is likely that some of the seams could leak into the wall cavity either behind or at least onto the failed moisture barrier. We suggest removing the coping and installing a complete secondary peel n seal barrier that can drain out to surface. We suggest new / wider coping is installed as part of the installation of the EIFS cladding. Even with the barrier we suggest all coping seams are set in sealant and pop rivoted or standing seams be used. LEAKING WINDOW PAN FLASHING The pan flashing at the window in the test area lacked proper end dams. It appears the window jams may have been set in sealants to originally create a sealant dam. The pan flashing did leak during testing although the leakage was very minor. We suggest the windows in these areas be wet glazed at mullion junctures and miters including sealing the corners of all gaskets. The bottom corners should have a hole carefully drilled areas cleaned with Q Tip & solvent and Sealant injected to create a sealant end dam at the outer corner of every window unit. The same could be applied at any pan flashing seams. We would suggest still leaving small weeps at the seal for incidental weepage. VENT PENETRATIONS The vent penetrations were not tested but we feel that they could potentially be a contributing factor to water flow into the failed moisture barrrier system. We suggest that during the course of repairs (especially if EIFS is installed), the vents be removed and proper / adequate pan flashings be installed to insure no water flow below the vents into the wall cavity. 3

5 EXECUTIVE SUMMARY (cont.) MISCELLANEOUS There was a reported leak area near the exits that we feel may be very well resulting from the previously discussed problems be may have a simpler source of leakage of the lower roof termination at the brick. There are several details at this transition that could allow water intrusion into the wall. The interior sheetrock is soft and 'bowing' in the area which is directly below the roof termination in question. There are several surrounding details we suggest are sealed as part of repairs (see photos & suggested scope of work) Suggested Scope of Work Follows Executive Summary Page. The results of this Leak evaluation reflects our opinions based on our experience and the limited time available for evaluation and assessement. We recognize that there may be more than one way to effectively correct the reported problems. We will be happy to discuss any alternatives desired. Repair contractors should specify their proposed methods and any applicable warranty. Moisture Consultants, Inc makes no warranty whatsoever for the success of repairs or the work of others. End of Executive Summary Scott Stephen Moisture Consultants, Inc. 4

6 Suggested Possible Scope of Work 1. Install EIFS cladding system over the Brick Veneer System. The intent is to 'forsake' the ineffective 'non barrier' system and create a new surface based barrier system with EIFS. Suggestions concerning the EIFS cladding: Use mechanically attached system Option: use tyvek barrier with new flashings and use of peel & seal to water manage If to be barrier with no tyvek we suggest extra application of base coat to insure proper EIFS lamina barrier Use available sealers for basecoat from EIFS manufactures No horizontal EIFS surfaces Specific details will need to be developed for transitions of new EIFS with copings, window heads, jams & sill flashings, terminations at lower roofs, terminations with roof flashings and vents. Moisture Consultants could assist with this item if desired. 2. Remove & Replace existing coping with New that will cover new EIFS down the wall at 3 inches. Install secondary barrier under coping and extend down both sides of exterior wall. Install in such a way to provide 100% water barrier before coping is installed. Insure secondary barrier can drain to surface at all terminating details. Set all coping seams in sealant and pop rivot or using standing seams. 3. Remove Vents and reinstall with proper pan flashings to properly prevent drainage behind EIFS and properly terminate under coping. Reinstall and insure proper sealant application at perimeters. 4. Check all roof terminations at copings & exterior wall junctures to insure proper lap and seal of laps and flashings. Insure adequate seal at all dissimilar materials. Modify terminations to insure proper transition with EIFS. (Some flashing extensions will likely be needed) 5. Wet glaze all elements of windows including mullion butt joints, miters, gasket miters, etc. Leave weeps in sill pan detail. Drill holes at face of casing at the sill pan, clean and inject sealants to create end dam. Modify / extend sill flashing to terminate on top of the new EIFS below. Reseal all perimeter of windows to new EIFS. 6. Seal lower roof terminations with Brick. Seal Stucco to Brick Transitions. Seal any penetrations through EIFS / Brick Seal underside of any head flashings to casings below. 5

7 Photo Documentation Typical corner section Building Managers office with Sheetrock removed Example of typical stains at window corners and damaged sills Thru wall flashings dont have proper end dams and have been attempted to be sealed to stone trim at window (leaked during testing) 6

8 Possible Water Intrusion Sources 7

9 Photo Documentation Vents create dormer and valley detail on metal roof Typical roof to wall transitions (blue - possible leak entry points) Typical Roof termination at brick wall. Likely minor sealing modification needed. Interior Leak Directly below RED Arrow Typical Roof termination at brick wall. Likely minor sealing modification needed. Typical vent detail Typical vent 8

10 Photo Documentation Typical Fixed window Unit (Pan will need to be extended with Addl flashing to cover EIFS Wet Glaze all mullions / gaskets and drill hole & inject sealants to create end dam (red arrow) Example of some of the details to be wet glazed. Seal gasket corners (blue arrow) Typical weep intended for drainage likely water intrusion point especially if building is under negative pressure 9

11 Photo Documentation Reported typical leak in hallway near entrances Leak has caused adhesion of floor mat to fail Roof transition in area of hall leak Seal roof transion, stucco to brick, window end dam and stucco to roof transitions Seal any gaps in roof to stucco transitions and stucco to brick transitions Seal underside of head flashing to window casing below. 10

12 Hydrodynamic Tests Test: 1 Duration: ~ 20 Min Date: LOCATION: BEQ Bldg 484 Building Managers Office Area DESCRIPTION: Hydrodynamic test of coping transition with brick and roof termination RESULTS No obvious visible leakage Observation / Comments: Stone coping appears to have roof membrane under it and turning up wall. Maintain all sealants at coping transitions - 11

13 Standing water entire length of thru wall flashing Test: 2 Leakage from test 2 in corner Leakage below faulty end dam Duration: 30 Min Date: LOCATION: DESCRIPTION: RESULTS BEQ Bldg 484 Building Managers Office Area Test of 1st set of brick weeps just above the stone coping Steady leakage below the end dam and at corner 6 ft away from immediate area. Observation / Comments: Thru wall flashing had standing water the entire length of wall section and was 3 inches deep at the improper end dam. Suspect failure of through wall / moisture barrier system primary cause of reported leakage. - 12

14 Detail Photos for page 14 Minor leak at window pan (no turned up pan) Test: 3 Duration: ~ 15 min Date: LOCATION: DESCRIPTION: RESULTS Observation / Comments: BEQ Bldg 484 Building Managers Office Area Test of window units Very small amount of leakage at end of pan flashing Suggest Wet glaze window units and inject sealants to improve end dams - see Executive Summary - 13

15 Leakage at window sill from framing Steady leakage below window Leakage below window Soaked carpet in corner Substantial waterflow into wall cavity from weeps Test: 4 Duration: > 15 Min Date: LOCATION: DESCRIPTION: RESULTS Observation / Comments: BEQ Bldg 484 Building Managers Office Area Hydrodynamic test of brick weeps above windows. Extensive leakage several areas including below window, on window sill, along floor soaking the carpet. Substantial leakage at the corner (several feet away) - 14

16 Detail Photos for page 14 Test: 5 Duration: ~ 20 min Date: LOCATION: DESCRIPTION: BEQ Bldg 484 Building Managers Office Area Test of Roof termination with brick and surrounding details in area of reported leak in hallway (typical) RESULTS No visible leakage. Observation / Comments: Area could be tested more extensively but time allotted would not permit. The same issues effecting the exterior walls could certainly be a contributing factor to this leak as well but it is also likely that the nearby roof termination and related flashings are the primary cause of this leak. See Executive Summary for general suggestions for this area. - 15