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Tezer
Jul 9, 2001



Motronic posted:

Now that's if you're trying to fix it right. What's this house worth and what's your repair/remodel budget? One or both of those may make it not feasible to do this "all the way." You may need to bite the bullet and put up some electric ice dam poo poo while the same roofer goes through half a roll of flashing to attempt to get water off of that roof in some meaningful way while the addition and the original house continue to move in different directions. FYI, that's what it looks like is happening here in part - and it could be foundation issues, it could be that the addition is simply rotting away at an accelerated pace.

Ya, if the corners of the kitchen addition are just piers, all they've got to do is start settling a little bit and the whole assembly where it attaches to the house will start pulling itself apart. There could be bulk water issues causing the leak, and air exfiltration issues causing the ice in the soffits - the building and specifically the roof is complicated so there is likely more than one way it's not working properly.


Epitope posted:

Details about contractors. I enjoy DIY, but I have no qualms about paying for a pro to do this. Just want them to actually fix it, and I have yet to meet one who will pay attention and actually think about what is going on. The previous owner paid for a six figure roof job, so clearly throwing money at it is no guarantee. He also sued the owner before, alleging faulty work.The home inspector was a joke, but I've had two roofing companies look, another home inspector, many contractor friends, and now an energy auditor with an infrared camera. Nobody has a diagnosis.Who else can I call? An engineer?

Motronic has it right, you want a good remodeler. The goal is to find someone with experience managing/performing multiple trades (since you have multiple overlapping issues), and also has experience fixing mistakes. A new construction outfit won't want the work (and they don't have experience with failing assemblies), and remodelers who just do kitchens/baths aren't going to have the experience needed to deal with what is an insulation/air sealing/framing issue.

Finding this contractor won't be easy, particularly because it's hard to figure out whether a specific contractor has the aptitude and interest to dig into the root cause of the issue as opposed to just papering over it. If you have a local green building/performance building supply shop, they might be able to recommend someone who takes that stuff seriously. You could also call in a building consultant, or ask one if they know someone in your area. Here are some examples of what I'm talking about. I really don't recommend this because it will be very expensive and just finding a good remodeler is a better course of action, but you might find it helpful to look at the language they use so you can better gauge whether a contractor is serious or not:
Building Science Corp: https://www.buildingscience.com/
Building Envelope Specialists: https://www.building-envelope-specialists.net/about/

Epitope posted:

The problem is a defect in an addition (ca. 1990s). Something about the design and/or the execution of the addition has caused water to get into structural elements. The rafters have been replaced. Twice (1999 and 2015). There is currently a large quantity of water (maybe a liter or more) in a section of rafters/roof decking, and more is accumulating/passing through.

Which rafters were replaced? If they are visible in the pictures, please label them.

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Tezer
Jul 9, 2001



Epitope posted:

There's no attic so I don't know really what it looks like in there. The "mouse hole" is as I understand it the vent between the soffit and the insulated run to the ridge. How much insulation and how much air space I can't guess. Are there other cross members? Did they get mouse holes? Dunno. I would bet there's not a ton of airflow between channels, but I highly doubt they're sealed from each other. Still, I have very little confidence the ventilation is correctly balanced anywhere, let alone in the problem spot. But point well taken, I won't start cutting more ridge vent as soon as it's above 40

We're getting away from your acute problem near the kitchen, but this is kind of the nature of your problem - a bunch of just not quite right decisions all working together to create a weird failure.

Today, when you build a cathedral ceiling the insulation and ventilation of the assembly is restricted by code to a limited number of configurations. This is done because as buildings have gotten more air-tight and insulation values have gone up, failures emerged in cathedral roofs. Warm, moisture-laden air rises inside the home, worms it's way into the roof, and condenses against the cold sheathing. A lot of these roofs still work because they are so leaky they manage to dry out anyways, but when they fail slowly it results in rot (might be why your rafters got replaced) and when they fail fast it results in what looks like leaks but is really just tons of condensation.

Here's my best guess with your main roof (ignoring the kitchen addition and the loft). It is probably insulated with fiberglass batts, it might have ventilation channels like Motronic mentioned or it might just have loose batts. At some point someone was told it needed to be ventilated, so a hole got cut at the soffit (in your pictures) and the ridge vent got added. Maybe they were original, but if they were original I don't know why the soffit vent is a round hole - that's something I can imagine doing while retrofitting an assembly, but a weird choice if it was built that way to begin with. There is likely zero air flow from rafter bay to rafter bay unless they drilled holes in each rafter, which structurally wouldn't have been a good idea so probably wasn't done.

Maybe some of this moisture is from roof ice-dams, but if it's really just all condensation (and it mostly looks like that - the ice crystals are depositing as opposed to flowing) the short term goal should be to limit the amount of warm, moist air that can get into these assemblies. To start, you need to figure out where it's getting in. You could hire someone, but given you're pretty invested in this and have had poor experiences so far, you might just want to take the first step yourself.

Buy something that will emit visible smoke so you can try and find small air movements. These are typically called "smoke pens" or "smoke pencils" or "smoke leak detectors". For big stuff you just straight up rent a fog machine, but you want something inexpensive and handheld. I just tried searching for them and stick "air leak" on the end of your search to avoid getting a lot of vaping results. Play around with it and see if you can start developing an idea of how warm air might be leaving your house.

Here's the first youtube link I pulled up, he shows how to use it to detect air flowing away from you, as well as air flowing towards you.
https://www.youtube.com/watch?v=1l_Vv5QjvTQ

Tezer
Jul 9, 2001



Motronic posted:

You are brave Tezer.

You also sound like you really know what the hell you are talking about. But yeah.....this is well beyond what is useful to someone in this position. This is a homeowner, not another contractor you are talking with.

Ya, but I figure everyone has time to kill these days.

I started writing "first, start removing trim" and then realized that kind of advice would lead nowhere good. Can't break anything or hurt yourself with a smoke pen.

Elviscat posted:

Also those nearly-flat skylights are the worst loving idea in snow country. Roof penetrations are difficult to seal well on high pitch roofs in places that don't have snow, a nearly-flat roof that builds up snow, and you better make drat sure you know what you're doing.

Agreed.

Tezer
Jul 9, 2001



This might help you find someone qualified. I know people who have this certification, but I don't have direct experience.
http://www.bpi.org/

Tezer
Jul 9, 2001



There's no harm in messing around a bit, seeing what you can figure out and mitigate on your own. However, given that these issues are likely related to pervasive construction quality issues coupled with brittle historic construction assembly decisions it's important to keep in the back of your mind that fixing everything "correctly" may require more money than the house is worth. That's what I take away from the more blunt comments in this thread, and I agree with them. I also agree with Motronic that sometimes ignorance is your best friend when it comes to property disclosures.

That said, there are plenty of houses with iffy assemblies that manage to limp along, and if you get lucky you might be able to wrestle your house into a better condition. I would never advise a client to start down this path because self-performance usually leads to crying. Just as a warning.


Epitope posted:

FLIR has happened, I had a guy out. I learned two things. Those things are not easy to use or interpret (he let me play with it). And unfortunately there's no obvious clue there. The guy I had out is a pro, but he was incredibly sloppy, so I'm planning on getting someone else out

Heat loss is a temperamental indicator when you are looking at a moisture issue and i'm not surprised you didn't learn much. You are trying to find locations where warm, moist air is leaving interior spaces and entering cold spaces, resulting in condensation. For this to show up in a heat loss study the temperature differential needs to be large (ok, it's winter so that works), but you also need a device that is sensitive enough to show the flow (this is a pixel size issue) and you need the flow to be large enough that the temperature differential can be detected before air to air mixing drops the temperature of the exfiltrating air to the point where it can't be distinguished. You'll have better luck if you pressurize the interior of the home, which generally is done with a blower door (maybe they did this?), but even then heat loss is the wrong tool for the job. You really want to look for air leakage with a smoke pen. Pressurizing with a blower door will help with a smoke test as well, if you are hiring someone to do this you will want it done with a blower door for best results.


Epitope posted:

Also, couldn't "poorly insulated windows" be part of the problem, and something that could be addressed with less invasive methods? Like, I get it, you and maybe any professional worth a drat is not going to see any point in dinking around with this stuff. But I have to. I can't commit to what sounds like a six figure rehab job without trying every other option first. And again, the previous owner did a six figure rehab job, and it didn't fix the problem.

Here's some more pictures of that window, with what looks like more interior air working it's way through.

They might be part of a different problem, but not the soffit problem. There is no path from the window into the areas of your soffit which are really an issue. If the condensation was on the interior of the glass, it might indicate an interior humidity issue that would exacerbate your soffit problem, but condensation on the exterior is usually just a 'cold glass' problem.

Hm, ok, now I've looked at the second picture and I see the ice and frost on the exterior trim. It could be a flashing issue on the exterior trim causing the bulk ice, but the frost is more interesting. If you are looking for another tool to buy, pick up a hygrometer so you can track interior humidity. If you search "cigar hygrometer" you can find cheap ones. Don't worry about buying a really accurate one, get a couple so you can figure out if one is super off. Like, I have one on my humidifier (winter), and my dehumidifier (summer), and a cheap analog dial stuck on my fridge. They all read 5-10% off from each other, but the goal is to figure out if your house is typically at 10% or 30% or 60% so accuracy isn't terribly important.


Epitope posted:

I did just go ahead and take off one piece of trim that's small enough I can put it back up easily. Used stir stick shim ftw

So, the trim comes off not to evaluate, but to repair. If this is an air exfiltration issue (and I know we've talked a lot about that, but technically it's still a guess!) the complete repair involves the removal of either all exterior siding and most of the sheathing, or the same on the interior, to install a complete vapor barrier in the correct location in the wall/ceiling assemblies. If that isn't possible, you identify the worst leaks and fill them with expanding foam/caulk/etc. That's where removing the trim comes in, as many of the worst exfiltration locations will be at places where materials transition and are discontinuous or have become discontinuous over the last fifty years. These locations are typically covered with trim, because that's what you do at those locations.

So, like, don't remove any trim unless you know the repair steps, because you'll just be creating a mess without a goal. Smoke testing, etc. can all be done without removing trim.

Motronic posted:

Except you don't know enough about any of that to matter. You're just wasting time here.

This isn't wrong...

If this is really interesting to you beyond just your acute issue, two good books on the subject:

"Moisture Control Handbook" by Joseph Lstiburek
"Water in Buildings" by William Rose

Lstiburek's book is more cut and dry, here are techniques, etc.
Rose's book is more of a textbook

Lstiburek will be more applicable to your acute issue, Rose is a easier introduction to the overall subject.

Tezer
Jul 9, 2001



Epitope posted:

In this case, the moist air is getting through penetrations at recessed lights. I assume the fix is either removing the lights or sealing them better. I guess my question is, could this fix be done with minimally invasive surgery? Like, cut out the light from inside, cap the wire, patch the insulation, patch the vapor barrier, patch the drywall, drink a beer?

You're in luck, I own the book. I like it because it never strays from core concepts. For example, the solution for that case study just lays out the basic reality: "condensation at a surface can be controlled by reducing the amount of moisture accessing the surface, elevating the temperature of the surface, or by removing the moisture once it gets to the surface". You can't do the second (requires reinsulating) or the third (requires rebuilding the assembly for proper ventilation), so you need to do the first. You can do the first by removing the moisture being transported (reducing the humidity in your home), removing access to the condensation surface (air sealing at the drywall plane), or by removing the transportation mechanism (depressurize your home so air tries to infiltrate your home instead of exfiltrate).

Air-sealing by removing the lights can be done, but don't do it until a professional who has seen your home says it needs to be done. If you have can lights in a cathedral ceiling it is "not good", but it also doesn't necessarily mean there is an issue or that it contributes to your other issues.

Like any thread, there is a bit of "blind men feeling an elephant" syndrome. We are reacting only to what we can see, which is what you are posting. We aren't diagnosing your home as much as we are diagnosing an incomplete model of your home. So hopefully the BPI contractor is a good one and can give you some answers. If they disagree with what this thread is telling you, keep in mind that no one in this thread has actually seen your home and this thread is probably just missing a key detail that is easily viewed onsite.

For example - is that really a bathroom right next to the soffit area where you have moisture issues? That is something worth investigating - for example, if the duct for the bathroom fan isn't properly sealed it would just be dumping warm, moist bathroom air into the roof right around where you're having issues.

Tezer
Jul 9, 2001



Epitope posted:

But when I bring up HRV he scoffs and says you don't need it (tone says they're a scam to bilk yuppies). Which, I still think it would help, but I don't really know. The one that's really throwing me for a loop is "oh that frost is normal." Like, what!? No, I'm pretty sure it's from the house cancer. Which it sounds like you agree I have, because you agree someone needs to come take down the cabinet and take down the drywall to find out what's going on. But not you though, you only do insurance jobs.

Also, "the work that's been done here is very high quality"

Frost is fine, until it starts damaging the building and then it is not fine.

An HRV should be used to establish balanced ventilation. It will help control interior humidity if you've got an existing issue, but that's just a byproduct of the way it works (similar to how air conditioning works - you buy the air conditioner to cool the air and dehumidification is just a nice byproduct).

Tezer
Jul 9, 2001



Epitope posted:

Which, we know there's a problem, right? This is a large part of my frustration. It looks scary to me, but what do I know, and I know it's easy to get carried away when self diagnosing. For example I was convinced I had torn cartilage in my knee, and didn't believe the clinician saying I was fine. Even the MRI may not have convinced me if they hadn't pointed out swelling and inflammation, which reminded me I had femoral patellar syndrome earlier, and this was probably just that flairing up again. So I can't just rely on my own judgement.

There is a problem in that soffit, we know this because the area has already been repaired once and continues to be wet when it shouldn't be. Stuff can be quirky, and you could just treat that area as a 'wear item' and replace it every couple of years, or use composite material so it isn't susceptible to rot. The same way you can baby one knee that you're having issues with instead of getting surgery, if the injury isn't disabling.

Honestly, I don't even think the soffit is a huge deal - I work on a lot of homes with wood trim and siding and there's always one area that due to various reasons (weird roof pitches, shaded so it doesn't dry, located right over a moist dryer vent) performs worse than other locations. What concerns me in your case is that you can't figure out why that soffit is an issue, which means that the issue could be more widespread and simply presenting in this location first.

Like, we have a client right now that has two issues on the exterior of their wood siding/trim home. One is the roof trim, which we are just going to replace. It gets hit with a lot of water, it's twenty years old, no big deal. The other area is a 5x5 area of siding that is showing rot within three feet of the foundation on one side of the home. We aren't repairing that one until spring, because we want to figure out why it's happening - it shouldn't be rotting in that area faster than others, so we are concerned that repairing it may just hide a more systemic issue.

Tezer
Jul 9, 2001



JLC has an article on using smoke to find air leaks, it's in their print edition but I don't think it's online yet. Here's a random PDF that has it though, starts on page 33 of the PDF:
http://www.bowe.cc/techlib/pdf/Journal_of_Light_Construction_vol39_no1_1604611416.pdf

Tezer
Jul 9, 2001



Epitope posted:

Here's the current list for a GC, if we can find one who's worth a drat that doesn't just nope out immediately.
-Turn skylight to roof (need to decide how much eave, especially on the side)
-Seal the window that clearly leaks. Do we need to remove (replace with wall) that window too? Might depend on the foundation...
-Seal the attic corner
-Fix/seal the LED outlet wiring
-Seal the kitchen vent pipe through the rafter box. (Also verify the pipe itself is installed well)
-Extend the ridge vent so it connects and we have ridge vent along the entire roof

Except for removing the skylights, this is largely a 'while you are here' list on a larger project, and even the skylight one I wouldn't do unless it was a customer with an existing relationship. I know you need to get this done, just cautioning you that it's a really unattractive list. Small piddly items. It's a list made for a handyman, except handymen aren't really trained in air sealing. It's going to be a frustrating process to find someone (sounds like it already has actually) and I sympathize.

Are you using the blower door to pressurize or depressurize your house, I didn't see that detail but perhaps I missed it.

Tezer
Jul 9, 2001



Epitope posted:

Ya

I've only set it to depressurize. I probably could put the fan outside if I wanted to go the other way, though i'm not sure the fan would withstand being stored outside. My home brew rig takes a lot of time and effort to place into the window, so I'd want to have my to-do list in order.

Since you're depressurizing, the cold temperatures observed at the kitchen hood ducting is understandable. Even if the roof cap has a damper, it won't be a good one so you will be drawing in exterior air down that ducting when you depressurize. this will show coldest where the ducting passes through other layers (like in your image) because at those points the ducts are cooling the materials that the duct is in contact with.

Maybe the damper could be improved, maybe the ducts could be sealed better, but overall it's not a result that is surprising.

It sounds like you've figured this out, just laying it out clearly to avoid more people saying you should rip the duct out.

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Tezer
Jul 9, 2001



Epitope posted:

(why is some yellow in there still, did they leave the previous foam in areas where it was still in reasonable condition?)

It's really annoying to remove spray foam, and literally impossible to remove it all without removing the material it's bonded too. They probably just left what they could.

quote:

Also while peering in there, I see something else that concerns me. The bottom of the rafter box has no wood just drywall, the sides are I believe rafters, and the top has plywood that sits on top of the rafters. The rafter in the back is the one that looks like it was chipped away to remove the rotten part. Above that chipped away part the plywood is dark/stained/(water damaged?). The rest looks like healthy raw plywood. So my concern is, did they frame the loft on top of roof decking? It kinda looks like they did. Is that bad? That seems bad to me. Decking needs to be replaced, and indeed just was replaced. Framing hopefully doesn't need replacing, or at least it's replacement is hopefully on a longer timescale. If that's what's going on, how big a deal is that? If they trimmed off the rotten decking that was under the roofing material, and now the remaining bit of plywood is acting as the loft wall sill plate or whatever you call it, how sketchy is that?

In the abstract, there is no problem building over the plywood decking. The new framing should have been properly blocked and fastened to the structure below. This is pretty common, especially when you're building an addition and you just frame over the existing roof and then cut into it once you're done (removing the shingles before framing, but not the plywood). I can't comment on how your particular loft was constructed, just noting that it's not unusual to see roof decking kicking around under a dormer/addition.

quote:

Do you (or anyone) know if I should provide a budget as I shop for contractors? Would a budget help me find someone? That is, can I make my list more attractive with dollars? Also, any idea of ballpark where that list will land? Is 50k optimistic?

Any contractor is going to have their own way of feeling out if a client is serious when it comes to money. You don't need to tell them your budget, just avoid saying things like 'affordable' and 'reasonable' which are secret code words that indicate you're a miser.

$50k is well more than enough for that list even for the people I work for, as long as stuff doesn't balloon (like, messing with the ridge vent doesn't turn into a roof replacement or something). I'd start conversations around removing the skylights since that is the largest 'real' project on the list, and talk about how it's part of general improvements you want to do regarding air sealing, etc. If you mention that you're fine with this being a fall project that will help, because everyone is busy and that way they know you won't fall out of the process when it becomes clear it won't happen in March. We are opening most client conversations by asking if they are OK with fall 2021 or spring 2022 and if they say no it really ends there.

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