Development pro formas have line items for materials, access, contingency, and marketing renderings full of implausibly happy people. Notice what didn’t make that list? Depositions. But judging by the numbers, maybe they should. Water intrusion has driven roughly 70% of construction defect claims this past decade, and some industry analyses tie as many as 80% of new construction lawsuits back to the building envelope.
While the building envelope makes up a modest slice of the overall construction budget, it boasts a wildly outsized share of developers’ legal risk.
When a defect lawsuit gets filed, the developer is usually the first defendant to be named on the complaint, with players like the design team and subcontractors getting pulled into the party on one side or the other as the case moves forward. But whoever ends up holding the bag, we see these five problems show up routinely.
1. The Devil is in the Details (That Nobody Can Reach)
Lots of contemporary buildings have small flat roofs over an architectural element like a bay window or tucked behind a feature parapet. These don't make it onto anyone's maintenance route because reaching them requires a good reason; that “good reason” is usually “we have an issue, and we think it’s coming from that roof we never go on”. And it’s not just roofs. Plenty of flashing details, soffits, and other conditions get installed in spots a contractor or facilities manager can barely squeeze into, let alone properly inspect, maintain, or repair later.
To make matters worse, those tight, awkward spaces don't get simpler details, they get more complicated ones. So you've got the hardest detailing on the project crammed into the spots where it's hardest to even see what you're doing. If the original installer could barely fit in there, odds are decent the work didn't go in exactly as designed the first time, particularly when it involved coordinating transitions with three other trades that also had no intention of coming back twice, correct sequencing be damned.
It doesn't stop with the installer, either. Everyone downstream has the same excuses for the same reasons. The contractor's foreman, the construction oversight consultant, the manufacturer’s rep, the facilities maintenance personnel: none of them want – and in some cases, physically can’t – access the inaccessible details to review their condition. And so they don’t.
But we are not here to make a case for getting OSHA Confined Space Training. The reality is that most of these fixes are design decisions, not construction ones, which means you have real leverage over it before a shovel ever hits the ground. Buildings (or at least the pretty ones) have character, and there are inherent complexities that come along with that. The goal is to be honest about which complexities earn their place and to coordinate the trades around the ones that do. Plenty of inaccessible conditions aren't even architectural features — they're coordination misses, like a structural engineer laying out roof dunnage without ever looking at the tapered insulation plan, leaving a 4-inch gap the contractor has to stick tiny fingers behind to "try" to roof well. Nobody designed that condition on purpose, and nobody can fix it cheaply afterward. Does that awkward roof valley on the backside a dormer add enough architectural intrigue to offset all the snow it collects? Probably not.
So give the features you keep real access paths, make the disciplines look at each other's drawings before things get located, and design with the mindset that someone will need to get back in there someday. And if a condition can't be made simple enough and accessible enough to build, inspect, and maintain properly, cut it altogether. It's a lot easier to delete a detail in design than to defend it in a deposition.
2. Walls That Can’t Get Rid of Water
Most wall assemblies are designed to manage water somehow; the cladding may be intended to keep the bulk of the water out during a precipitation event, but not all of it. Water getting past the cladding, therefore, isn’t a failure. The failure is when water gets in and then can't get back out, or ends up beyond where it was ever supposed to be.
A rainscreen – a cladding system with a drainage cavity behind it – is about as close to a gold-standard, building-envelope-nerd-approved wall system as it gets, because it all but removes the most common reason cladding systems fail: poor drainage. Water that reaches the cavity has a dedicated space to, with the assistance of gravity and some flashing at the base of the wall, run down and out. What it doesn’t do is sit against your water-resistive barrier (WRB) – the layer that ultimately protects your structure from water damage – until warm enough temperatures can dry it out via evaporation. The better drained a wall is, the less weight your WRB has to carry on its own. Water that goes in and stays in does far more damage than water that goes in and leaves.
The trouble starts when value engineering gets a hold of these drainage mechanisms. Cut the cavity, skip the drainage mat, tighten up the cladding attachment to save a half-inch of wall thickness. Now you’ve removed the one fully passive thing standing between a wall that drains and dries and a wall that doesn't, and the WRB goes from being a part of the drainage system to your entire water-management defense.
The design should think about wall performance holistically, with a clear water management strategy, rather than component by component or material by material. The details should show a clear understanding of how the wall manages water from top to bottom; is the design intent to shed water? To drain it internally? To dry out? The answer should be clear, if for no other reason than knowing the risks associated.
3. Window Mock-Ups, Window Schmock-Ups
Olympians don’t compete without a practice run. Broadway performers don’t go on without running through their lines or warming up their vocals. The rehearsal is where the tweaking and adjusting happens, while a mistake still costs next to nothing. In the construction world, that “rehearsal” is the mock-up and field testing. It's an opportunity to catch or clarify confusing or non-constructible details and figure out the necessary sequencing between trades, before the same condition gets repeated across an entire building.
Not every detail needs this treatment; the ones that do are either complex or repeated a lot. Windows check both boxes, and window installation is one of the most common sources of bad detailing and inadequate field testing in new construction. An error we see often is windows being water tested per ASTM E1105 (the standard field test for checking whether an installed window keeps water out) way too late in construction, if they get tested at all. There’s both good and bad news that comes with late field testing. The good news is you may have caught a systemic installation problem before the project is complete. The bad news is that every single window may now need to be redone, and that change order is a sucker punch to both the budget and the construction schedule.
In-field performance testing shouldn't be a box you check because the specifications say so, and it definitely shouldn't happen after you've already done the majority of the installation work. Test early. Get a handful of windows in (say 5 out of 100) and test those before you install number 6. If the test yields any undesirable results, fix what turns up before it gets repeated ninety-five more times. Sealant joints – of which nearly four out of five construction lawsuits name as deficient – are another strong example. Nobody wants to redo 10,000 linear feet of sealant over an adhesion issue that a mock-up and some early field testing could have caught. The same logic applies to any repetitive envelope component.
4. Can You Peer Review Our 90% CDs?
Okay, we may have some bias here, but this is a real problem we see way too often: peer reviews that happen way too late in the project.
Peer review is almost always good, but the returns diminish fast once the building envelope systems have been selected, the budget's locked, and a schedule is set. A late review can still tell you what's wrong — you just can't do much about it anymore. With limited pivot room, what you end up with is a stack of redesign recommendations nobody can feasibly act on. You paid for insurance and received a souvenir.
Instead, get the peer review done early, during design development or the early construction document phase at the latest, not after every envelope system is picked and the budget and schedule are set in stone. More detailed supplementary reviews should follow as the design progresses, but that first one needs to happen while the key project decisions are still on the table.
5. Cheaping Out on the Important Things
Value engineering: dressed up as design optimization but, more times than not, a cost cutting exercise made with financial blinders on. Do we really need a drainage plane? Does the WRB have to be that one? And to be fair, on paper a lot of cladding systems, WRBs, and other envelope components do look interchangeable. But you have to look at the whole picture. If the rainscreen and drainage mat from #2 already got VE'd out earlier in the process, your bargain-basement WRB is now the only thing standing between the weather and that fancy new "luxury" building you're developing. Get rid of the belt and you probably don’t want to let go of the suspenders too.
Summation
If there's a theme here, it's that the decade of litigation data keeps teaching the same lesson: envelope failures are among the most preventable defects in construction, and they can be prevented during design and early construction, when you still hold the pen. None of this is meant to scare you off ambitious buildings — it's meant to get the envelope some attention while attention is still cheap. If you'd like another set of eyes on your next project before the systems get picked and the budget gets locked, we're happy to talk. We're also a lot cheaper than the attorneys.