October 20, 1989

The Aetna Casualty And Surety
P.O. Box 911
Houston, TX. 77001

Attention: Mrs. Phyllis Hoffpauir

Reference: Engineering Investigation of Window Leakage
 Insured: Ryland Homes, Inc.
 D/L: August 1, 1989
 Client Claim No. Il61 LTT Multi Claimants
 KESCORP file No. 96340

Dear Mrs. Hoffpauir

On August 11, 1989 you requested Knight Engineering Services Company, KESCORP, to investigate the cause for leakage at windows in many new hones located in the Clear Lake City area. These homes were constructed by your insured, Ryland Homes Incorporated.  The leakage occurred on August 1, 1989 during the storm Chantal. Of primary concern is a determination of  cause for leakage relative to possible defects in the windows.

On August 15, 1989, the investigation was initiated with a site visit accompanied by you, and Mr. Jeff Larson and Mr. Chris Newman both of Ryland Homes Inc. During that visit windows of five homes were examined, one of which was under construction with the windows uninstalled and stored in the garage. Several windows were tested by spraying water on their exterior.

On August 16, 1989 another visit was made to the Ryland Homes warehouse facility to examine other new window units. This visit was accompanied by you, several representatives of Ryland Homes Inc. and several representatives of General Aluminum Corporation, the manufacturer of the windows. During this visit several window units were examined and two were tested.

On October 18, 1989 another visit was made to the Ryland Homes warehouse to meet with Mr. Ray Woodruff and Mr. Dan Chaney. During that visit I examined a storm window, made by Living Windows Company, as a possible fix for the many leaking windows. During that visit I also examined other General Aluminum window units including one which they now propose, for new construction, to prevent the leakage problems experienced on their windows.

It is my understanding that Ryland Homes has now authorized me, at their expense, to witness testing by a certified window testing laboratory, of some of the window units that are the subject of this investigation. [They did perform these tests. The results will be online soon.]The schedule for this testing is tentatively the week of October 30, 1989.

Based upon the findings of this investigation conclusions have been established as shown on the attached page. If we can be of further service on this or any other problem please call.

Sincerely,

KNIGHT ENGINEERING SERVICES COMPANY

Weldon H. Knight, P.E.
 
 

1. The cause of window leakage in many Ryland Homes, during the storm of August 1, 1989, was numerous defects in the windows as manufactured by General Aluminum Corporation, Dallas, Texas.

2. Heavy leakage resulted from a drainage defect in the window/screen arrangement that caused flooding over the window's inside lip seal.

3. Heavy leakage into the walls resulted from inadequate sealant, or no sealant at all, on the lower corners of the window frames.

4. It is probable that many other leakage complaints have not been recognized as coming from the unsealed window corners.

5. Leakage around window panes resulted from the following manufacturing defects:

a. Bonding of the panes was defective, probably due to delays in the manufacturing process that allowed the sealant to surface dry before contacting the glass.

b. Many window panes are undersized and some are installed in bowed out framing, thereby lacking adequate seal contact between the glass and window frame.

c. The inner frames of the multiple pane windows are too fragile and flexible, resulting in excessive stress on the seal bond and premature failure of the seal.

d. Inadequate attachment of the inner frame to the outer frame allows excessive deflection of the panes, producing failure of the seals.

e. Reglazing of General Aluminum's window panes requires special and unreasonable procedures, unknown by the general public and believed to be unknown by most trained reglazing craftsmen.

6. It is unreasonable to require homeowners and repair personnel to be trained in special procedures for repair of a window pane.

7. It is probable that these multiple pane windows will be a continual source of major leakage for the homeowner.

8. It is recommended that the multiple pane window halves be replaced with single pane window halves to reduce the; probability of leakage.

9. It is not probable that thc General Aluminum windows conform to the AAIlA 101R25 with the screen in place and with wind pressure applied.
 
 

INTRODUCTION

On August 11, 1989, Mrs. Phyllis Hoffpauir of Aetna Casualty & Surety requested Knight Engineering Services Company, KESCORP, to investigate the cause for water leakage through windows of many residences constructed by Ryland Homes, Inc. The window leakage occurred during the wind driven rains of tropical storm Chantal on August 1, 1989, in the area of Clear Lake City, Texas. Window leakage was reported by approximately 400 residents of Ryland Homes in that area. [It was learned much later that homeowners in Pasadena, League City, Spring, Missouri city, and more in 4 different counties were affected] Of primary concern is a determination of cause for the leakage.

INVESTIGATION

On August 15, 1989, an investigation was initiated with a site visit accompanied by Ms. Phyllis Hoffpauir of Aetna Casualty & Surety, and Mr. Jeff Larson and Mr. Chris Newman, both of Ryland Homes, Inc. During that visit, four homes were examined that reportedly had profuse leakage during the storm. Those homes examined were as follows:

1. The residence of Mr. Billy Goodman at 14626 Cardinal Creek Court.[This is MY street. Billy lives 4 doors from me.]
2. The residence of Mrs. Montalvo at 1502 Chestnut SpringsDrive.
3. The residence of Mrs. Chavez at 947 Mulberry.
4. A Ryland Home which is "For Sale" at 14207 Oak Chase.[This owner filed suit against ryland homes for the windows. Theses studies were NEVER disclosed to him.]
5. Uninstalled windows were examined at a Ryland Home under construction, address unknown.

The windows that leaked were manufactured by General Aluminum Corporation, P. O. Box 819022, Dallas, Texas 75381. The windows reported to have leaked included several sizes. Some were narrow, approximately 24" wide by approximately 6'-0" high, some others were approximately 4'-4" wide by 6'-0" high, others were approximately 4'-4' wide by 3'-0" high. Other various sizes were also examined, photos 1-2.

Flooding over the window's inside lip

Most of the complaints by homeowners reported that water flooded over the inner lip of the lower window frame and produced flooding across the sill and onto the floor. Tests were conducted whereby we sprayed water with a garden hose onto the exterior of several windows. This problem was simulated with the hose by lightly spraying 3 gallons per minute of water onto the windows, photos 4-12. Care was taken to avoid any concentrated squirting. At that flow rate the leakage was duplicated, producing flooding over the bottom lip of the window frame.

This flooding resulted from the bottom frame of the window screen holding the water at an elevation sufficient to cause flooding over the inner lip of the window frame. The screen was examined and found to be tight fitting at the bottom. It had such a tight fit that water seepage from beneath the screen frame was inadequate to prevent the water buildup. It is to be noted that this test was conducted with no simulation of wind pressure on the outside of the window. Any wind pressure would have greatly increased the flooding over the inside lip. The lip inside the window, is protected from the wind pressure outside the window.

We advised the owners of the homes we inspected, that this type of flooding could be prevented by simply loosening the window screen frame from the bottom of the window during heavy rain storms. This prevents entrapment of the water in the bottom of the window frame. However, we believe that the window manufacturer should redesign the screen and/or window to prevent this problem.

Leakage around individual window panes

Other leakage reported by all homeowners, was the numerous areas where water seeped in around the edges of individual window panes. Examination of these panes revealed incomplete bonding of the sealant between the frame and the glass. Many of these leaks resulted from a very small overlap of glass over the frame. Many of the overlaps were no more than 1/16 inch. A few were observed to have no overlap at all. Many of the windows had sufficient overlap but lacked an adhering bond between the glass and the sealant.

It was reported by Mr. Bud Cartwright of Ryland Homes, Inc., that during visits to other window manufacturing facilities he had noticed delays in the glazing process, between the time the sealant was applied to the frames and the time the glass was laid on the sealant. He had further noticed delays between the time the glass was laid on the sealant and the time that it was pressed into the sealant with the rigid vinyl snap in glazing beads. He believed that delays of this type allowed time for the sealant to partially dry before contacting the glass. He expressed concern that delays of this type may be the cause for weak bonding on these windows.

Our findings included those of window panes laying in contact with, but unbonded to the sealant. This finding bears evidence that Mr. Cartwright's analysis of the bonding problem may well be the cause for this type of leakage. It is probable that the defective bonding results from delays in applying the glass to the sealant and from further delays in applying pressure to the joint.

Leaks to the inside of the walls

Several of the homeowners complained that water entered their homes at the baseboards of walls. These leaks were found to be adjacent to windows. Other homeowners complained that water came through walls adjacent to the bottom of windows installed in high places, for example, where the ceilings were vaulted. These reports led us to wonder about the seal at the lower corners of the window frames.

Examination of the lower inside corners of the window frames  revealed no sealant inside those corners. To examine the outside of the frame corners would require removing the windows from the wall. We chose to examine some new windows before they were installed. We visited the site of a new Ryland home that had the windows stored in the garage.

Several of the new windows were found to have inadequate sealant applied to the exterior of the lower corner framing joints. Most of the sealing defects were found to be areas where the sealant had not been extended up to seal the end of the inner lip, photos 26-34. A test was conducted with one of these windows. Photos 35-38 show a large spillage of water pouring from a typical unsealed inner lip. Approximately 20% of the joints were found to have this defect. If these windows had been installed in that condition, they would have produced severe leakage to the interior of the wall during heavy rain storms. During examination of other new window frames, (at a meeting in the Ryland Homes warehouse, to be discussed later) some of the lower frame corner joints were found to have no sealant at all, photos 27-28.

It is believed probable that many complaints have resulted from this defect. Two of the three homeowners that complained of water running out from under the baseboards had not determine where the water was entering the wall. They had not realized that it was a problem with the window seals. It is believed probable that there are many leakage complaints that have not yet been properly attributed to the window leakage problem.

Inner/outer framing defects

Another leakage problem found with these windows is inadequate attachment of the inner frame components to the heavier outside framing. This inadequate attachment results from two different causes. First, the outer framing, in some cases, is bowed outward beyond the end of the inner frame piece. This was found to be most prevalent on the top frame piece and is believed to be caused by picking the window up at the center of the top frame. Since the glass was still bonded to both frames on some of the new windows with this problem, it is apparent that the outer frame was bowed during the manufacturing process, before the sealant was cured. Second, the inner frame piece appears to be too short and does not reach the outer frame.

In either case the tabs on the inner frame piece fail to engage a support slot on the outer frame, photos 22-25. This defect compromises the strength and integrity of the window and results in excessive stresses being applied to the bonded joint between the glass and the outer frame. The additional stresses cause failure of the bond between glass and frame, producing glass deflections of 1/2" to 3/4" from the outside framing. It is apparent that wind pressure will deflect this assembly of disjointed frame sections and will cause heavy leakage during wind and rain storms.

Under sized panes

Another defect found in the window units was undersized and improperly cut window panes. Many of the panes are believed to be undersized and result in inadequate overlap at several sides of the glass. It is believed that this problem results from poor dimension control by the glass cutters or from bowed framing as described above

Reglazing problems 

Another problem of leakage found with the windows is that of reglazing the window panes. Many panes have required reglazing in an attempt to stop the numerous leaks. It was reported that Northwest Glass Company currently holds the contract for reglazing of these windows. The reglazing jobs that we observed appeared to be very sloppy, and with incomplete seals around the perimeter of the panes.  This problem is discussed further on page 5 of this report.

Meeting with General Aluminum personnel

On August 16, 1989, a visit was made to the warehouse facility of Ryland Homes, Inc. at 1310 East Richey Road, Houston, Texas. This meeting was attended by Mrs.. Phyllis Hoffpauir, of Aetna Casualty & Surety, Mr.. Dan Chaney and Mr. Steve Jones, both of Ryland Building Systems, and Mr. George Colvin, sales representative for General Aluminum Corporation and Mr. Douglas Effler, director of engineering for General Aluminum Corporation.

During this meeting several new, uninstalled windows were examined and two were tested. All of the previously mentioned problems were found and pointed out to the representatives of General Aluminum Corporation.

During those discussions, we first pointed out the cause of the greatest leakage as being damming of water by the screen frame. We also demonstrated, with a level, that the top of the screen frame is essentially the same elevation as the top of the lip inside the window. We further pointed out that any wind pressure would greatly add to the leakage problem. We pointed out that the bottom of the screen frame fits too tightly, and thereby prevents sufficient drainage from the window frame, to accommodate heavy rainstorms.

We recommended some modification be made to the screens that would allow more water to drain from the entrapped area. Mr. Effler strongly opposed our suggestion, stating only that the windows were not hurricane proof and that they had passed the AAMA specification 101-85. This specification is discussed later in this report.

Regardless of whether or not these windows pass those tests, it is apparent that the windows failed to prevent water infiltration in some four hundred residences during the Chantal storm. Chantal's winds, measured 33 ft above open water, were barely classified as hurricane velocity (75mph). Its winds were quickly dissipated once it reached land. Since the winds are greatly reduced near the ground by trees, buildings and other appendages, it is probable that these windows were never exposed to winds of more than 39 mph, the minimum wind velocity required by AAMA 101-85.

It is apparent that a window that holds water in the bottom of the frame is of a very poor design. It is further apparent that when the bottom of the window is full of water, any outside wind pressure will produce flooding over the lip seal and into the residence. We contend that these screens should be modified to alleviate the problem of entrapped water.

AAMA Specification 101-R25

This specification label appears on each window unit, photo 3. A copy of this specification is included as exhibit I. The water resistance portion of this specification calls for a test method described ATM E 547-83.

Exhibit II, ie the 1986 version of that specification and is believed to be representative of the 1983 version. The product label specifies conformance to specifications for DH (double hung) R (residential) and 25 (pounds per square foot structural design pressure). The table on page 23 shows this window unit to be an optional class with a water resistance test pressure of 3.75 pounds per square foot. This reflects a wind pressure of 0.72 inches of water column that is produced by a wind velocity of 39 mph, exhibit III. Since the lip on the inside of the window frame is only 1/2 inch high, it is apparent that this window cannot possibly conform to this specification if any water accumulation exists between the window and screen. Any water accumulation would obviously be pressured over a 0.50" high lip by a pressure of 0.72" water column. We are very doubtful that these windows comply with the tests required. We recommend that arrangements be made for our witness of tests to be conducted on some of these windows.[See the second report which shows the windows did not pass the tests even with the storm windows attached.]

Leakage at lower corners of the windows

We showed Mr. Effler several of their new window units that had no lower corner sealant whatsoever. He was also shown numerous other window units that had incomplete seals. Most of these were failures to extend sealant up the end of the inner lip. Mr.. Effler did acknowledge that the missing and incomplete seals were defects in their manufacturing process. He reported that their quality control department had recently initiated a requirement for applying sealant at the lower corners inside the frame as well as outside the frame. It is believed probable that much of the leakage resulted from this defect. It is also believed that many of the residents, reporting leakage at the baseboards, are not aware that this leakage is coming from the windows. It is probable that many of those residents are inclined to think that type of leakage (along baseboards) is caused by some construction defect in the brick work, siding or roofing. [This is almost funny. Ryland claims the water could not get ou of the house becasue the weep holes were plugged up. They took every 3rd brick from thelottom layer and removed, cleaned out the back side and replace the brink.]

We believe the leakage at these corners can be stopped by application of sealant inside the lower corners of the frame. However, It is important to make sure the sealant is extended up along the vertical leg of the inner lip.

Reglazing of window panes

During discussions with Mr. Effler, director of engineering for General Aluminum Corporation, he stated that reglazing of these windows is easily 'messed up' if the repairman does not adhere to the proper procedures. He reports that removal of the glass must be done very carefully. He further reports that one must preheat, and soften, the sealant at the edge of the pane so the pane can be gently released without disturbing the seal of the adjacent panes. He further indicates that excessive heating or deflecting of the framing can easily cause other leaks in adjacent panes. Mr.. Effler further advises that installation of new panes requires equally careful handling. He indicates that one must avoid deflecting the inside framing while applying just the right amount of heat and pressure to the glass.

We believe this delicate heating and handling is a problem, especially while installing the rigid vinyl snap in glazing beads. It is apparent from discussions with Mr. Effler that the inner framing is not suitably rigid to allow untrained persons to replace a window without causing other leaks in adjacent panes.

We believe that these windows are unduly susceptible to development of leaks due to the flexibility of the inner framing components and to the apparent fragile bond between glass, sealant and frame. We further believe that the required procedure for replacing these panes, is not common knowledge to the public. We believe that these windows are, in all probability, an ongoing leakage problem that will repeatedly plague the homeowners. [Ryland attempted to reglaze the windows. This was their first plan which they stated to us in their second letter. It failed miserably. They could not get the windows to stop leaking.]

Design chanqe recommendation

We believe this problem will exist as long as the individual inside framing pieces are used. It is our opinion that the numerous small individual panes should be replaced with a large single pane. This design will eliminate the delicate inner framing that will otherwise cause many future leakage problems for the homeowners. If a small pane appearance is desired, we recommend the use of paste on framing, as used by many other aluminum window manufacturers.

Changing to the larger panes will reduce the total length of sealed joints by a factor of 2- 1/2 to 3 for a typical window. Assume for instance that a window half contains six small panes with one foot on each side. Then the total length of sealing for those six panes is 24 feet. On the other hand, if those six panes were replaced with a single large pane, the total length of sealing would be only 1O feet. I\t should also be noted that the entire length of sealing for the large pane would be on a heavier exterior frame that is much less lightly to cause a leak. A similar comparison for use of a single pane in lieu of nine small panes, reduces the sealing length to only l/3rd of the nine pane's sealing length.

Recent Imorovement Considerations

On October 18, 1989 we made another visit to the Ryland Homes Warehouse facility to meet with tin Ray Woodruff and Mr. Dan Chaney, to discuss the possible use of storm windows to resolve the defects found in the General Aluminum windows, photo 39. The storm windows appear to be an acceptable method of covering the defects of the General Aluminum windows. However, they may not be acceptable to all homeowners. The enclosed space between windows may also cause higher temperatures that could become an additional problem for the sealant. [I believe this is EXACTLY what happened to my windows, and my neighbors windows.] We recommend the window assemblies be tested, with the storm windows in place, to evaluate their service probability relative to water, wind and temperature.[See the second report which shows the windows did not pass the tests even with the storm windows attached.]

During that visit we observed a double pane window by General Aluminum Corporation which they now offer as an improvement for future construction, to prevent the problems of past construction. These windows reportedly differ from the previous design only by having the large double panes that eliminate the small inside frames and their numerous sealing problems. We believe this to be a good step in the right direction. We also noticed the sample double pane window unit had an improved bottom frame piece with a 1" high inside lip seal as compared to the 1/2" high lip seal on previous window units, photos 40-41. This improvement is interpreted as an acknowledgement by General Aluminum Corporation, that their previous windows with only 1/2" high lip seal were defectively inadequate.

Although both of the above changes are good, we noticed this sample window still had the defective seals at the lower corners of the frame. We noticed that sealant had been applied to the inside of the corners as well as to the outside of the corners, as tar. Effler indicated they were starting to do. However, on this new sample window, the sealant both inside and outside failed to seal the end of the inside lip seal. This defect was observed to be on both bottom corners of the window, photos 42-46. If these defective seals are not properly repaired they will continue to cause leakage into the inside of the walls as described earlier in this report.

We are most concerned that the above improvements fail to consider the problem that caused the greatest amount of leakage, that of water entrapment by the tight fitting screen frames. The screen frames were observed to hold 1/2" of water inside the lip seal. If 1/2" of water is held inside the bottom frame when a wind pressure of 0.72" water column occurs, even the new 1" high lip seal is inadequate to prevent leakage through the window. This condition would require a lip seal 1.22" high. The obvious alternative is to modify the screen frames so they will drain properly. If this is done the 1" high seal would be adequate.

1. The cause of window leakage in many Ryland Homes, during the storm of August 1, 1989, was numerous defects in the windows as manufactured by General Aluminum Corporation, Dallas, Texas.

2. Heavy leakage resulted from a drainage defect in the window/screen arrangement that caused flooding over the window's inside lip seal.

3. Heavy leakage into the walls resulted from inadequate sealant, or no sealant at all, on the lower corners of the window frames.

4. It is probably that many other leakage complaints have naot been recognized as coming from the unsealed window corners.

5. Leakage around window panes resulted from the following manufacturing defects:
 

a. Bonding of the panes was defective, probably due to delays in the manufacturing process that allowed the sealant~ to surface dry before contacting the glass.

b. Many window panes are undersized and some are installed in bowed out framing, thereby lacking adequate seal contact between the glass and window frame.

c. The inner frames of the multiple pane windows are too fragile and flexible, resulting in excessive stress on the seal bond and premature failure of the seal.

d. Inadequate attachment of the inner frame to the outer frame allows excessive deflection of the panes, producing failure of the seals.

e. Reglazing of General Aluminum's window panes requires special and unreasonable procedures, unknown by the general public and believed to be unknown by most trained reglazing craftsmen.

6. It is unreasonable to require homeowners and repair personnel to be trained in special procedures for repair ' of a window pane.

7. It is probable that these multiple pane windows will be a continual source of major leakage for the homeowner.

8. It is recommended that the multiple pane window halves be replaced with single pane window halves to reduce the prouability of leakage.

9. It is not probable that thc General Aluminum windows do not conform to the AAMA 101-r25 R25 with the screen in place and with wind pressure applied.