Our house came with a beautiful cornice that was attached to and supported by the parapet behind it. It was constructed out of copper, but the bottom section had been painted, unfortunately.
It has terrified me for years. This was because upon closer inspection, the top of the cornice was in dire need of repair and we had water infiltration issues, which led the supporting parapet to crumble. And no matter who I asked, I never got a straight answer on how it actually was constructed, supported or attached to the building. It remained shrouded in mystery, leaving me to procrastinate.
With the looming solar array installation, there was no avoiding this any longer. I opened up the top copper sheet to get a visual on the inside and the attachment mechanism – or lack thereof. And the more I started digging the more terrifying it got.
The “support mechanism” was rotting pine boards, which were rotting either in the masonry or the opposite end. And the supporting masonry had deteriorated into loosely stacked bricks.
The crumbling masonry had to be removed and rebuilt. The bottom of the cornice was salvageable, but the top sheet had to be entirely replaced to prevent any further water infiltration into the masonry behind. Mind you, the job of the cornice is to shed water away from the building façade. Along with all this we needed a new support mechanism.
To save and reuse the bottom section of the cornice, I had to brace it before I could remove and repair any of the masonry or top copper sheet. The last thing I wanted was for it to fall off the building.
I managed to score a stack of reclaimed two by fours at The Rebuilding Exchange, which I used to rig up a solid bracing system.
I threw a lot of loose brick scraps around. And after having reached rock solid layers of brick, I was ready to test my masonry skills again.
I learned early on in the project that the combination of a 100+ year old building and Chicago common brick requires not just any mortar, but a special kind of mortar – the Type O kind.
The mortar joints in these masonry walls are meant to be the sacrificial layers – because they are easy to repair through tuck pointing. Replacing damaged bricks is much more involved and labor intensive. To prevent brick damage or spalling, and to assure a functioning sacrificial joint, the mortar needs to be softer than the brick. That is where the Type O comes in handy, if used in combination with our common brick.
For more details and rationales on the Type O mortar, read my earlier post: Bricks and mortar.
To make the mortar work and have it properly cure, I had to prevent it from drying out. The common brick is a very effective sponge, and can suck the moisture out of mortar within a few minutes – unless the common brick is already wet.
Before I could slap any mortar onto the bricks, I needed to spray down the existing masonry wall and soak the replacement bricks in a bucket of water. And believe me, one quick spray or one quick dunk won’t do it. Common brick is a sponge, and it needs wetting like a sponge.
Once the tedious due diligence is out the way, I was ready to slap mortar on the bricks and start rebuilding the top of our south wall, so that we could get to building the roof level of our new back porch.
I am glad that the time lapse doesn’t provide any close-up view, because my masonry skills are OK yet still basic. In other words, my work is not that purdy! Do I care? No! Not as long as the work is sturdy. That part of the wall will be covered with a big old ledger anyways.
Edgar, our carpenter, and I had a number of conversations this spring, thinking through the process of rebuilding the back porch. Back then, he pointed out that we would encounter a lot of loose bricks right at roof level.
That prediction didn’t surprise me because this section of the masonry wall isn’t that dissimilar to the parapet. And boy, that parapet was in bad shape, until we rebuilt it.
Removing the loose bricks was somewhat of a déjà vu with some subtle differences.
The only whole bricks I encountered were on the outside. The inner wythe was almost completely composed of brick scraps. This must have been the last bit of masonry work when they raised the walls. Was this resource efficiency or did they simply run out of good bricks? Whatever it was, the extensive use of brick scraps didn’t produce very solid masonry.
I had to pull out all those loose bricks until I was down to solid masonry again.
When we insulated the second floor, I didn’t insulate behind the last roof joist. There simply wasn’t enough room to get into those two inches between the joist and the masonry wall.
Now, with the brick removed, I had all the space I needed to get into that space and insulate it with pieces of two inch thick XPS boards. I can’t lose sight of the air tight building envelope principle. So I made sure to seal around all the XPS edges with spray foam.
The west facing kitchen window is so tall (or reaches so low for that matter), that any cabinet with a countertop would partially block it. I assume that the original kitchen layout must have been such that no counter was located at the window – which wouldn’t have left much room for countertop space.
Or, the previous owners were content with the countertop partially blocking the window. This is a scenario I dislike as the window sill hidden behind the kitchen cabinet is hard to reach and would just accumulate… well – let your imagination roam.
I really am curious as to what the original kitchen layout may have been!
Anyway, we already solved this problem in the 1st floor kitchen, and were to repeat it on the 2nd floor – by raising the bottom of the window above the countertop height.
This means getting rid of the existing window altogether and calling our mason.
The masonry work was a big deal for me, but not so for the mason. “Just half a days’ work…” Great, then I can spend the other half day on building and installing a new window buck.
The process is similar to the range hood exhaust installation. I use the hammer drill with a masonry bit to drill out the mortar joints and set up a perforation line across the brick. Once that is done, I can grab a hammer and chisel and carve out the joist pocket.
In the kitchen at the chimney, the two joists stop short of the masonry wall. I placed a sister joist mock up along the roof joist, which allowed me to mark the exact location for the joist pocket. As for all the pockets, it was a tight space to work in. Nevertheless, the pockets turned out all right, and a test placement confirmed that the sistered joists would fit right in.