A few months ago I came across an article from DWM Magazine (DWM = Door and Window Market) about a lawsuit filed on Oklahoma against Pella Corp by a homeowner that alleged the Architect Series windows have design and manufacturing defects as result they are leaking and causing premature wood rot and damage. You can read the article here: https://www.dwmmag.com/lawsuit-alleges-pella-architect-series-windows-were-defective/
Replacement windows come in a wide range of options and price points – unfortunately paying more doesn’t always equal greater quality when choosing a replacement window (and if you have your original windows they most likely can be repaired and as energy efficient as replacement windows – science backs this.) You can read more here: https://practicalpreservationservices.com/put-replacement-windows-to-shame-what-that-nice-salesperson-doesnt-want-you-to-know/
Reading the article about the lawsuit against Pella I wasn’t surprised by the issue the homeowner had. They had purchased aluminum clad (wood wrapped in aluminum) ‘designed and manufactured to protect the wood’ and I’m sure they also tout the maintenance free aspect of the design. The complaint alleges, “[An] investigation revealed that the defendant’s Architect Series windows aluminum exterior cladding had design and manufacturing defects allowing rain water to drip in to the interior wood and that the rain water dripping in to the interior wood over the years resulted in rotted wood internal destruction of the windows.” This is a common issue when wrapping wood (I won’t even get into the fact that the pine they are using is inferior to old growth wood) and is one of the reasons the Secretary of the Interior advocates for NOT wrapping wood in metal or synthetic siding: https://www.nps.gov/tps/how-to-preserve/briefs/8-aluminum-vinyl-siding.htm
“Since aluminum and vinyl sidings are typically marketed as home improvement items, they are frequently applied to buildings in need of maintenance and repair. This can result in concealing problems which are the early warning signs of deterioration. Minor uncorrected problems can progress to the point where expensive, major repairs to the structure become necessary.
If there is a hidden source of water entry within the wall or leakage from the roof, the installation of any new siding will not solve problems of deterioration and rotting that are occurring within the wall. If deferred maintenance has allowed water to enter the wall through deteriorated gutters and downspouts, for example, the cosmetic surface application of siding will not arrest these problems. In fact, if the gutters and downspouts are not repaired, such problems may become exaggerated because water may be channeled behind the siding. In addition to drastically reducing the efficiency of most types of wall insulation, such excessive moisture levels within the wall can contribute to problems with interior finishes such as paints or wallpaper, causing peeling, blistering or staining of the finishes.”
Trapping the water behind the metal and against the wood is the same issue that is being alleged as a design fault in the Pella lawsuit. The lawsuit also alleges that the company had known this was a design defect since 2006 (there had been previous class action litigation). The complaint sums this up, “[Pella] breached its duty to disclose to plaintiff that its Architect Series windows had a substantial risk of leaking because of design and manufacturing defects and that the leakage would result in rotted wood and that after the purchase of the windows defendant breached its duty to inform plaintiff that defendant’s Architect Series windows had a very high likelihood of leaking that would result in rotted wood”.
As I stated previously I wasn’t surprised by the cladding causing wood rot and I do think a window manufacturer should understand this and design to avoid the condition, but most people move every 7 years and if the previous homeowner paid the expense of replacement windows when the windows begin to fail it is a ‘necessary’ cost of maintaining a home and the replacement cycle continues.