Cathedral ceilings: so not worth it
Herfrontdoor
| Posted in GBA Pro Help on
I need a guru to point me in the right direction for a remedy to water literally running down my walls on the inside of my living room when the weather freezes and then thaws. I’m in Minnesota zone 6b. I’ve already replaced walls and low parts of ceiling back in 2013
Now it’s happening again…
Now it’s happening again…
My 3/4 loft home has a cathedral ceiling. Open ceiling over 1/4 of 1st floor. It is prefab home with a full basement built in 2000. Baffles and fiberglass and ridge vent with soffit vents, etc. No ice dams until 2013.
1st ice dam occurred in 2013 – water coming down from where the roof meets the walls. Tore out baffles and sheet rock in damaged area. Replaced fiberglass insulation with closed cell spray (in tear out area only- not the whole ceiling).I think baffles or something similar were also replaced in the damaged area. Replaced the sheet rock. There is no canned lighting in the ceiling- only flat mounted lights.
2nd water problem happened last year. Water was leaking down the walls.snow and then thaw. Ice cables and gutter heaters were installed , hoping that would fix the problem.
3rd time 2019 Feb. Not alot of snow this time but walls damaged again from water inside the living room yesterday when it warmed up to above 30 degees after deep freeze (-50 below to +40 in less than 48 hours). Water was literally pouring down my sidewalls where roof connects to the wall. Sheet rock and paint even bubbled where water seeped in.
Roof and siding was redone 2010. Roofers are out of business now. Did they miss something maybe?
I also started using my exterior door more (located directly under the damaged area) about the same time of the first water damage incident occurred. Should i not be using this door at all if it creates a problem since it located right below the water damage in the same room with the cathedral ceiling? The heat register is also near the door and also directly below the bad area.
Future projects moving forward…
1.I wanted to install covered porch/deck with a handicap ramp on that side of house also.
2.Also want to install metal roof in future…at least on the north problem side. Would this maybe help with Ice dam problems too? Was hoping to add solar panels to south side someday too.
Would a covered deck off and/or metal roof help..make it worse or have no effect at all?
Do I start with a roof & install a vapor barrier layer on existing plywood decking?
Or do i need to start from the inside and redo the insulation? (Cringing at the thought)
I want to avoid doing the interior surface if I am already doing the exterior surface on the roof part.
Before I talk to anyone, what is my next move?
Who should I talk to first and what do I look for?
Roofing expert?
Insulation expert?
Home energy audit with thermo imaging?
I’m truly at a loss. I don’t want to throw more money (and a bad band aid remedy) towards a bad situation AGAIN.
Thanks you all for allowing me to post my problem here and for any advice you gurus can offer.
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Replies
Sounds to me like your roofers either skipped installing ice and water shield on the lower part of the roof, or they didn’t run it up far enough on the roof. That’s probably why water is getting into your walls. Ice and water shield is an adhered membrane that goes down under the shingles and felt to shed any water that manages to get under the shingles and keep it from soaking the sheathing and getting inside. Ice damns are the classic problem that ice and water shield protects against.
Your ice damns are forming due to insufficient insulation, a leaky ceiling, or a combination of both. If your roof has a very shallow pitch, the venting won’t work well and then you have that as an added problem. My preference is closed cell spray foam for the entire cathedral ceiling since it’s safer. Also, if you spray foamed only a small are, you might have caused ventilation issues in other areas depending on how and where it was done.
A metal roof may help shed snow and ice better, but won’t necasarily prevent ice damns from forming.
I’d say you need both a roofer and an insulation contractor, and they both need to be competent. You need the roof to be checked and probably at least partially redone. Someone is going to have to pull up some shingles and see what’s going on. My money is on missing or insufficient ice and water shield.
The insulation needs to be checked and fixed. There are various ways to do this and it’s hard to give you good advice without some detail about the way your roof is framed and vented. My first thought is to apply closed cell spray foam everywhere, or at least do flash and batt (saves some money). If you need a new roof, exterior rigid foam is also an option. Since you had water come inside multiple times, there is a good chance you have at least some damaged sheathing.
Can you provide any pics of the damaged areas? Especially pics of inside the ceiling in the damaged areas? That would help everyone here to give you better advice.
Bill
HerFrontDoor,
First of all, can you tell us your name? (I'm Martin.)
Ice dams are almost always caused by leakage of interior air into the roof assembly. The solution almost always involves air sealing work.
You don't want to ask a roofer for help. You need to talk to a home performance contractor -- someone equipped with a blower door and an infrared camera.
For more information on this issue, see these two articles:
"Prevent Ice Dams With Air Sealing and Insulation"
"Ice Dam Basics"
She has not actually told us she has ice dams. In fact, the recent melting issue occurred with little snow, but very cold conditions. This sounds more like condensation within the roof cavity than ice damming. In very cold conditions, the moisture condenses and freezes in the cavity. A rapid warm-up then allows all of that ice to melt and run back down inside.
Interventions that fix ice dams sometimes help with internal condensation, but not always. In fact, it can make it worse if it interferes with ventilation of the underside of the sheathing.
Either way, you still need a good home performance contractor to figure out which one it is, and to address it properly.
Peter,
Good points. I agree. Condensation and frost buildup is common in cathedral ceilings.
The common thread between that type of problem and ice dams is that air leakage is almost always the culprit. The solution is usually (a) to make sure that the ceiling is airtight, and (b) to make sure that there are no hidden air pathways from walls or partitions to the ceiling assembly, and (c) to add insulation if necessary -- but only if the air sealing work is also addressed.
I would consider reroofing the area giving you problems, I agree with others, the roof is leaking. Once this is done you can devise a ceiling assembly that will be energy efficient and durable. GBA has provided all the information on cathedral ceilings one needs to decide on the best system for your application.
Cathedral ceilings properly executed are trouble free, correct details for your climate and housing type must be adhered to.
A properly installed roof should not leak, even with ice dams. I did ice dam remediation for my neighbor in Minneapolis last winter. There was a lot of ice near the eaves due to warm air leakage and insulation that was less than 1/2 of current code. The roof did not leak because the recently installed roof was done properly with ice and water shield to code or beyond.
The adding of a dedicated air space below the roof sheathing, reusing existing fiberglass batts and 3" of room side Polyiso foil taped and sealed to the walls has solved the ice dam problem. The work was done in January with varying portions of the roof deck exposed for a time. There may have been a bit of frost on the plywood but never any dripping of water. A typical MN house in the winter without humidification will be very dry, ours (3 ach50)currently is under 25% . There may be other factors adding humidity to the house like a high water table but generally inside air will be dry.
Doug,
You wrote, "I agree with others, the roof is leaking."
My response is, "Hunh?"
I don't think the roof is leaking. I think warm air is leaking out of the house. The warm air is either (a) melting snow on the roof and creating ice dams, or (b) causing condensation or frost on the underside of the cold sheathing, or (c) both.
This is not a roofing problem. This is an air barrier problem.
Martin,
I agree there is an air barrier problem as well, but the amount of water coming in sounds like a deficiency in the roofing system. Were it me I would at least consider the roofing as part of the equation. Ice dams on a properly roofed house should not cause bulk water intrusion. I run ice and water shield well beyond code minimums up from the exterior wall line. I also put a layer of ice and water under valley flashing for the entire length. I have done more roofs than I care to admit but so far have had no call backs. I can't know when roofing the thermal properties below but I can take extra precautions to see the roof does not leak in extreme conditions.
I've seen gallons of water pouring down from many inches of ice that built up under the roof sheathing. It's almost never the roofing as I'm always called to help after owners just replaced their roof after the previous spring thaw. Huge pools build up where rafter bay meets wall plate then gushes in. I'm sure humid air is screaming up the walls into the rafter bays. I have a hunch the lighting junction boxes are not sealed as well.
Also if the room exposed timber like a ridge beam, not done properly (which they never are), this is a huge source of air leaks. Getting these sealed after the fact might be more work than sprayfoaming the roof.
Thank you all so much for the replies.
There was no visual ice dam when this happened and not much snow see photo. Heat cables were indeed working but did not help. After reading the discussion, I'm going to start looking for a good credited home performance contractor. I've never heard the term before but it sounds like that is type of pro I need for this.
This only occurs when there cold and then a suddenly thaw. Yikes! It's only February.
I'm very grateful for this site and your opinions.
Marie
The amount of snow and ice you’re showing is not enough to be causing enough of a problem to be leaking in. With those new pics, I’m also going to side with the “it’s probably air leakage” crowd. Chances are enough moisture is getting into your ceiling assembly, condensing and freezing on the underside of the roof sheathing, and then thawing when it warms up outside to cause the issues you’re seeing.
One thing I didn’t see in your post is anything about your indoor humidity levels. It seems odd to me that you’re seeing so much water coming in from moisture accumulation and not a roof leak. Are you perhaps running a humidifier? If you are, that’s almost certainly where all that extra moisture is coming from. You should reduce the humidity setpoint as a bandaid until your contractors are able to locate and fix the issues with the ceiling assembly. Those same contractors can also advise you as to the safe upper limits for indoor humidity in your home.
Bill
Marie,
A consensus is building: in all likelihood, your ceiling is very leaky-- that is, it has enough cracks and holes to allow warm air to escape and enter your rafter cavities -- and your indoor relative humidity is elevated. In cold weather, condensation and frost builds up on the underside of your roof sheathing; once warm weather arrives, the frost melts and your ceiling leaks.
It's very unlikely that this is a roofing problem -- so stay away from roofers.