Brick joints
JLopez
| Posted in General Questions on
Hi, climate 2 , brick veneer exterior home. I’m replacing wall in my garage , I noticed the brick joints are missing mortar in many of joints , should I fill them in with mortar or not ? Or will it cause problems if I do like moisture buildup ? Thanks
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That looks like the backside of the brick. That is how it typically looks. A bit too much mortar in some areas squished through, a bit shy in other areas. If the photo os the backside (the side you would typically never see, this is normal and not a cause for concern.
It is the back side . And oh ok I just thought it was an ugly case of mortar . Would it hurt to fill them in for reducing any drafts that carry moisture and for stronger structural exterior walls?
If it's just brick veneer, it won't make much difference but won't hurt anything.
You are aware that you need to keep any metal brick ties in place, right? And the lateral bracing that the wood fiberboard provides?
Thanks for the advice .
The gaps should only be backside gaps; the mortar on the front side should be continuous.
As such, there should not be any opportunity for bulk water or air to come through the brick.
Also, the brick should not be your air barrier...so filling the backside gaps will not address the issues you noted.
Further, in order to do so, you are going to need to remove the sheathing, and that is a very poor idea. The brick ties should be attached at the studs, and as Michael notes, they should not be removed. But there is clear evidence there is a cut tie in the upper left of your photo. That is going to destabalize the brick.
In this install, the brick is your bulk water barrier, but a brick/mortar system is moisture permeable, so when it gets sopping wet, water can migrate through it to the back side. You do NOT want to lock moisture into the brick.
The space between the back of the brick and the sheathing is your "rain screen" gap. It allows any stray bulk water that gets past the brick and mortar to run down the wall and hopefully out at the bottom. The brick wall should have weeps at the bottom that let this water out.
The sheating ought to both provide structural integrity and an air / vapor barrier. You install appears to be fiberboard, which is not so good at any of those tasks. If it does not get wet, it may stay in good shape, and can be somewhat of an air barrier. However, when they installed this stuff, they did not typically seal it around the permimeter. It was touted as having more insulation value than plywood. You may find plywood at the corners, and you may find horizontal metal bars in some locations to provide additional structural rigidity.
Your photo shows no insulation as you noted in a previous post that this was removed from the garage. Had you done this at a conditioned space, you would have probably seen figerglass batt insulation between the studs.
The gypsum board on the interior acts as the air barrier, which is a fairly typical situation.
You noted you want to stop moisture migration but don't want to remove either the brick or the siding at the gable ends. In that case, leave the sheathing alone.
One possibility given your constraints is that you could remove the gyp board from the inside, and do a "cut & cobble" in each stud bay of 1/2" or more rigid insulation, and seal it all around to the studs. This would get you both an air and vapor barrier. You could also seal all jboxes and other penetrations. Then reinstall the fiberglass (you could probably learn to do a MUCH better job than a typical insulation contractor, but fiberglass is nasty; wear PPE). Then reinstall all the interior gyp board. This is a relatively inefficient way to get an air and vapor barrier as it is labor intensive to do a proper job. It is also messy inside, which is why most people approach the issue from the exterior.
Overall, you are probably best off to begin by trying to identify the locations of the air leaks in your house and addressing those. Do some googling aobut how to use a fog machine to identify those locations, and then address them.
My reasoning for wanting to fill in the brick joints was because on the outside of the brick wall the mortar seems to get cracks and holes and u fill them in and they reappear after a few months . I removed the fiberboard because it was damp and I was able to take it apart with my hand since it crumbled in some areas . I’m going to replace with osb . Just that section of the wall . I probably won’t attempt to do the whole wall on my own . I’m going to focus on the air leaks, but with a non-condition garage and attic that is vented., Any advice where not to seal? I don’t want to trap moisture in . It’s just kind of confusing because I’ve been told by some to let the wall breathe ,
If there is an issue at the exterior with the mortar, then it may need repointing. Adding mortar from the back side is not going to fix that issue.
If the fiberboard was damp and crumbled, it sounds like bulk water is getting behind the brick. At the area where the fiberboard was damp, what is above the brick wall? Is this at a gable end with the Hardie siding above it? It could be the top of the brick was not properly flashed before the Hardie was installed, and that would allow bulk water behind the brick. Given your siding installer did not insist on installing sheathing onto the framing behind the siding, there may be other gaps in their knowledge.
It is going to be difficult to replace that section with OSB - you will have to cut the OSB the width of the stud bay, then attach nailers to the inside of the OSB, then slide it in and attach the nailers to the sides of the studs. I'd consider replacing with rigid insulation (cut & cobble method). That will at least keep moisture out of that stud bay.
Regarding where to air seal, you want to seal between conditioned and non conditioned space. So at the ceiling of the living space to seal it from the unconditioned attic. You also seal at the perimeter of the conditioned space.
You also want to keep bulk moisture out of all walls - those between conditioned and unconditioned spaces, and those between two unconditioned spaces such as your garage.
What specific action are you planning that has you concerned about trapping moisture?
Suggest you get a copy of Allison Bailes book "A House Needs to Breathe or Does It?" before you start. You will probably find reading it helpful.
The area above the brick is the gable end with hardy siding and house wrap There is no flashing above the brick . The house wrap seems to terminate just below the area of the first brick in front of it , not behind the brick and sealed with sealant at the end (I know this because on the exterior portion where siding meets brick there’s sealant filing that gap). Is it supose to be sealed or no?
So, . I went up to the attic last night to check the area where the house wrap starts above and it’s wrapped over the top of the first siding (towards the exterior , well barely , some of the house wrap is not even wrapped over ,‘some of it was too short were I can see the top of the siding . And it’s not sealed continuously. Some of the wrap was in a lifted position ( I guess the wind lifted ). I used my hand to feel and a stethoscope camera to find my findings ). I had to do alot of twisting of the stethoscopes wire to see a few angles ( I need a better one ) but anyways . I bought some home depo brand house wrap and cut it to the length of space between the studs , I’m working on small sections. I started at the bottom , overlapped the existing house wrap about 4-6 inches and taped the bottom of the new piece with sikaflex insulation tape , taped the sides but getting the tape to stick from the top and getting it to stick to whatever is in that area (wood eave area) , was difficult cuz my fingers only reach so far and the tape is not sticking well. So I used gorilla waterproof tape and that was able to stick onto whatever it touched and stay. Not sure how to secure the top , I can try to see if a staple gun fits in that little 2 -3 inch opening area .
Oh and the moisture I’m dealing with is high humidity . Some of the walls feel damp , my ceiling inside house some of it was starting to sag and I added insulation from soffit I that area and seemed to help . My floors heave sometimes, some days it looks normal , I know the garage wall attached to house the studs are damp because I can see vertical lines where wall paint is darker where each stud is.
I added about 5 new aluminum soffits and had a ridge vent added in the roof valley at other end of house about 9 months ago or so. I don’t know if having these new openings have contributed to any water vapor in air , I didn’t notice any issues with any of these except during the winter , the master bedroom where ridge vent was added was colder than before and I could feel the wind draft . As far as my hvac , I know there is leaks which I have used foil tape to seal any tears . I suspect it’s oversized and the supply vent in a cavity in the closet in the house that goes up to attic . Before it was drywall and studs that led up to the big ugly foil looking box in the attic . I had a tech seal the closet cavity , duct board was used and mastic. The bottom of the closet is bare concrete covered in duct board . A few months ago the AC vents in ceiling would sometimes spit droplets of water cuz I could feel them . Very minimal . Supply box and handler are located in attic yes I know not good . , the flex ducts down of them are tied near the roof ceiling and where they exit the other box next to handler 3 ducts are touching each other . Also the refrigerant cooler line runs through and at one point taped to one of the flex ducts . If I had the money, I would redo the whole Hvac system, it will have to wait till it breaks . I do suspect there is air pressure differences thru the house , air leaks are hard to deal because when I try to seal another bubble pops up on the caulk or spray foam , I recently hung a curtain on wall by AC condenser located outside and the curtain rod hardware popped back out . All 3 hangers , I screwed them in . I had to tape and super glue them to stay on.
RE: top of brick / bottom of Hardie - Yes there is supposed to be flashing. Take a photo of this from the exterior, and draw and post a cross section for what you think is happening behind - no idea really you are trying to describe.
If, as you write, you had a "ridge vent added at the roof valley" you have a problem. Ridge vents belong at the ridge.
Not really sure about what you are describing with all that other stuff.
Your best next move is to read Allison Bailes book "A House Needs to Breathe or Does It" and become familiar with systems and terms. It will also give you a good understanding of things you can take on to improve your situation.
I wanted to help ventilate the attic so the roofer recommended installing air channels like the ones on ridge vents on the valley . I guess I need to cover it up . Thanks I’ll see if I can buy a copy of Allison’s book . And sure I’ll do the drawing. And can u explain to me what cut and cobble mean. ? I can’t find anything to help me picture what u mean
Read this about attic ventilation:
https://iibec.org/attic-ventilation-101/
Read this about the cut & cobble method:
https://www.greenbuildingadvisor.com/article/cut-and-cobble-insulation
Read Allison Bailes book:
https://www.energyvanguard.com/book-house-needs-breathe-or-does-it/