I really hoped that I wouldn’t have to report on another house-vs.-water bout (Rounds One and Two having been decided in my favor), but the Forces of Nature had other ideas. Was the third time going to follow suit, or was the tide – no pun intended – turning? This bout took place in February 2022.
You might recall that Ed Costanzo of General Brick Designs, who led the campaigns in 2018 and 2019, continues to perform regular scans of all waterproofing jobs. The underground dam that was installed in the front yard in 2019 was continuing to do exactly as designed and intended, but a backyard scan revealed a very large pool of water directly beneath the family room in the northwest corner of the house. Where was the water coming from now?
A systematic ‘mapping’ scan revealed another underground stream following the general path shown by the aqua-blue line. It was crossing under the back patio and ending up against
the foundation of the west-facing wall of the family room (yes, those are steps without a door; it’s an explanation for another day, lol) within the area bounded in blue; and
the adjacent north wall of that same room, formed by the northwest corner. The water had carved itself a ‘bowl’ beneath this room, resulting in the walls, both below and above grade, being at almost 100% moisture levels.
At the other end of the stream’s path, a water-filled subterranean sinkhole was visible on my neighbor’s side of the white vinyl fence. Although hard to discern from this angle, the deepest depression is circled in red, and a less-sunk area circled in purple. There was, no doubt, a ‘bowl’ of water there as well, and all of the excess was making a beeline for my house.
The solution – as it had been for the front-yard stream issue – was to prevent the water from getting where it has been going, i.e., under my house. This too would require an underground dam but of a slightly different type than the 2019 one; that one had been (my description, not Eddie’s) a “diffusing diverter”, but this situation would require a “blocking diverter”. The photo above shows the dam’s shape and planned location (yellow line), the incoming stream (aqua line) and then its path after encountering the dam (blue line.) The purpose of the zig-zag shape is to slow the water’s speed as well as change its direction.
The good news is that the dam’s ideal location wasn’t either under the patio or within a planting bed. The only garden resident needing to be evicted was a Magnolia soulangeana that I’d inherited along with the house. Truth be told, I was dismayed that the magnolia had been covered with powdery mildew all last summer, for some reason, and I’d pruned it by more than 1/3 last November to give it a more open shape and better air circulation.
The scope of work included not only the dam (made of 4000 psi concrete and #5 steel rebar) but also digging out (and cutting in, on the interior basement side) the affected foundation areas and footings and underpinning them with concrete and steel against further damage. After seeing the bottom line, I knew I must wave goodbye to my crumbling-driveway and south-patio replacements (which, ironically, I had been planning to select the pavers for, at the masonry yard, that very afternoon) because the water control job would wipe out my funds for those things…and then some. ☹
That afternoon, I vented my frustration against All Things Water by getting a head start on disposing of the magnolia. I’d have cut it to the ground if my branch saw had been capable of it! (One of these days I really should buy myself a Sawz-All.)
Day #1, Saturday
Eddie and his crew were actually able to start the job the next morning. They began by laying out the location and cutting the outer edges of the shape. Then the excavation began. Two huge tarps were deployed for dirt-pile locations. This all had to be dug by hand.
The far end of the first pile is the topsoil, and you can see the progression in color the farther down the trench went. The wheelbarrow track led to pile #2,
which you can see in the background of this photo!
Day #2, Monday
More digging, which now had to deal with an overnight snowfall! The previous day had been almost 50 degrees. Crazy weather. The crew also started on building the forms and shoring up the sides of the trench
Also begun today was the exposing of the north (family room) foundation wall. This provided a surprise that did not surprise me too much, in view of what I’d already discovered about the house’s previous owners. Quick backstory:
The house, as built in 1962, had no garage. The original owners had a two-car garage added in 1965, along with a 12’x19′ covered, concrete patio directly behind it. (They also created an illegal apartment in the basement, but that’ll be the subject of another Money Pit Tale.) In 1996 they reduced the garage by about 40% in order to add a half-bathroom and create a family room on the same footprint as the 1965 covered patio slab. A subsequent owner reduced the garage even more (it is not even a one-car garage now) to create a full bath and a washer-dryer area, and also installed the large paved patio that you see in my first photo. Whoever built that patio chose to put it on a 14″-thick concrete base (why??) which eliminated any possibility of exposing that west-facing foundation wall. Naturally.
Today’s unwelcome discovery was that the foundation of the original patio – upon which the 11’x18’ family room now sits – was constructed without any footings. Footings are critical because they not only support the foundation walls but also transfer the load (structure’s weight) to a larger area, thus keeping the structure as a whole from settling over time. Whoever built the patio didn’t bother to pour any footings, and whoever approved the permits and CO for the 1996 family room didn’t care whether the existing foundation had footings or not. This, sadly, is typical. The yellow arrow points to the original cement-patio slab from 1965 upon which two courses of cinderblocks and then the family room’s structure were then placed. The white PVC pipe was a dead electrical line to some backyard post-lamps that I’d had removed two years ago, so out it went.
Today was also the day that a section of the basement floor was cut away, in order to give access to the area where the family room structure joins the original basement. The red arrows point to upstairs walls where scans indicated a very high moisture content wicking up from the foundation levels. The inside of the wall directly above the right-hand arrow (entrance to the family room) was extremely wet. Also, notice the wall section with the yellow X, to the right; that black is not paint, it is asphalt-based tar (damp-proofing compound) that was applied to the interior wall not only here but on most of the other basement walls as well, and then covered with fiberglass insulation and drywall so that it was not visible until the basement had to be torn out (another Tale.) This is totally against building code because this stuff is only meant for exterior walls. The only saving grace is that because it has been there for so many years, it has stopped off-gassing…. or so I hope.
Day #3, Tuesday
The steel rebar reinforcing structure is created inside what will be the actual dam.
The northwest part of the family room foundation gets some sealer before the reinforcement goes in. Ideally, the entire 11-foot width of this wall would get the same treatment, except that the air conditioning compressor is located in front of almost half of it.
It was also discovered that the 1996 geniuses simply dry-stacked the cinderblocks rather than doing it correctly, i.e., with mortar joints. No wonder I was having to kill ant colonies inside this very section, three years ago.
Day #4, Wednesday
The cement truck cameth! But unlike the front-yard dam, the truck could not pull up right next to the trench. Nor could a chute be used for this particular very dense, very fast-setting mix because it would clog up too quickly along the necessary length. This meant that every square inch of the concrete had to be wheelbarrowed by hand by Eddie’s crew, probably almost 100 feet to the farthest end of the dam, and a good 40 or 50 feet even to the closest part.
Freshly filled concrete forms, at about 12:30 pm. Yup, there’s still snow and it’s still cold.
By mid to late afternoon, it has ‘set’ enough to allow backfilling to begin.
Yes, the second pile is gradually getting smaller; but there is a third pile, untouched, on the driveway.
Reinforcement of that north family room foundation.
The yellow arrow points to the spot where the family room structure joins the original garage, which is on a slab. Whoever built the garage did at least use mortar joints on the inside! This photo also shows the percentage of the family room wall that could not be addressed because of the AC compressor.
Eddie’s crew created proper mortar joints between the cinderblocks.
Day #5, Thursday
Day Five was the final one of the project, and can be subtitled “Backfilling and Finishing”.
Timberlite mulch replaced atop the excavated north wall area.
The cut-out area of the basement floor was dug out and the area beneath (which was more open space than soil, thanks to the water coming in and going out for so long) was reinforced with concrete and rebar. It should not fill up with water again, which should – over the next months – allow things to dry out in this area. New concrete closes up the cut-out.
And I even got a new mailbox. I won’t show the one that was here, other than to say that it was on a wood post and had long been nicknamed The Leaning Tower. This is a steel box, on a steel post, bolted into a 16” square and quite deep brand-new concrete pad. All it needs now is some plants!
I definitely see grass seed in my April future. But otherwise, would anyone ever guess at all the work that had been done here?!?
Soil piles? What soil piles??
One Week After Day #1
The mortar joints are now almost the same color as the blocks. The ants will need to find somewhere else to set up housekeeping from now on!
I also discovered a silver lining to the magnolia being gone, as I was walking into the kitchen that morning and happened to glance out the window that is over the sink:
A perfect view of the coral bark maple ‘Sango Kaku’ in all its red-limbed glory. The magnolia had hidden most of it from view when seen from the house.
Now there is a cheery midwinter sight while doing the dishes! And the October-November view will be great also, as the leaves turn to gold.
Follow-up scans during the next weeks and months will give a clear picture of what that stream is now doing, and how quickly the foundation and house walls are drying out. If this works as well as the front-yard dam has done, Eddie and his crew will have again scored a win for me in Round Three!