Stones, Walls, and How Not to Renovate a Basement – OA-11, BcGn-15

Dee Vaz

When we (Team Fox) arrived at the area of operation we were assigned, we were greeted by an intriguing hollow in the ground covered loosely in sticks with what appeared to be an intentional build-up of large stones in the ground (Fig. 1).

We deliberated for several minutes about where to place our unit before we began digging so that we would be able to expose what we could see in the hollow, as well as attempt to find a wall which lined up with the previously excavated house walls in OA-8 to the west. Initially we settled on a centrally placed 3x2m unit (Fig. 2), but quickly realized that we would need to extend it eastward in order to more substantially uncover what seemed to be a rapidly appearing stone wall. Therefore, we continued our excavations with a 3x3m unit removing the topsoil/organic layer or context 1 (removing a significant number of stones and rocks along the way). By the time we stopped to revaluate context identifications we had the presence of a substantial stone wall that visually appeared to be collapsing to one side and held several large stones in the centre that likely fell from the top of the wall, as the stones still in tact on the highest level were rather loose (Fig. 3).

Before making any further decisions regarding the assigning of any further contexts we attempted to further define what we could already see. Of particular interest was the southeast corner of the unit, the wall seemed to slant downwards in that direction and unlike the northeast corner of the unit, where we had what appeared to be a corner of the wall, the architecture here was much less clear. After a considerable amount of troweling (my new favourite way to disassociate), I revealed several more nonsensical rocks and a few voids (Fig. 4). Nothing much could be concluded other than we needed to go deeper. We cleaned up a few more areas in the unit in preparation for planning. Following that, we assigned new contexts and readied ourselves for the next steps; dig down and continue the great game of “Is it a Rock or Did I Just Accidentally Destroy a Piece of Wall?”.

Now we get serious, and steadily remove context 107 (the central fill and debris on the inside of the wall). Finally some things start to reveal themselves as we find two large cut stones that connect the northeast corner of the wall to the thus far non-descript, collection of partially revealed stones in the northwest corner (Fig. 5). We hypothesized that these stones may be set lower than the other walls in order to act as a door jamb of sorts, but further excavation proves that this is unlikely. Instead, the upper wall material was likely pushed into the fill during the destruction period.  

In the inner corner of the stone wall, we reveal a large broken iron pipe behind some stone debris (Fig. 6), and hypothesize that it may have some connection to the thinner pipe and divot in the ground found just to the east of OA-11. At this point we thought perhaps it might’ve been a well, the pipe connecting to an irrigation system of sorts. As it turns out, this piece of pipe was actually connected to a pipe that was built into the stone wall leading directly toward what we thought might’ve been a well, more on that later.  

We’re finally getting somewhere, our feature looks much more like a wall as opposed to a collection of rocks and stone that happens to fall in a rectangular shape (Fig. 7). However, the southeast corner is still presenting an issue, we have still not found the continuation, if there even is one.  

Now what do we do when we need to work through a small, specific area that’s covered in stones that may or may not be associated with a portion of wall? If you said grab a trowel and disassociate, you’re absolutely correct. I uncovered the remaining portion of the wall in the southeast corner of OA-11 and confirmed that it continued directly into the south wall of the unit. At the same time, I revealed a clump of large stones held together with mortar resembling those within the wall, but these were not inline with it (Fig. 8). This is likely a piece of the same wall that was broken and pushed out of line during the destruction phase.  

We’ve now established the extent of the wall’s boundaries within OA-11 (Fig. 9). Now, we find the floor. We knew, thanks to Grace’s expert analysis (falling through the floor) and many voids in the unit, that we still had quite a way to dig before we reached it and since we were closing in on the final few days of excavation, we knew it would be a time crunch but the end was in sight, and we were determined to complete the unit.

Remember how I said all we had to do was dig down context 107 to find the floor of the basement and the end was nearly in sight 5 seconds ago? Forget I said that, I lied. On the second last day of excavation me and meddling trowel hit an evenly poured ledge of concrete at the base of the stone wall that spanned the entire length of it (Fig. 10). Thus far we’d been hypothesizing that these stone walls were part of the original house’s cellar, but if the stonework was supported by a concrete foundation, that would push our wall dates significantly earlier. Don’t worry, we still had only a single day of excavation to figure this out…no big deal.

As it turns out, the stone walls still likely belonged to the original house when this area made up a crawl space (crisis averted), the concrete was added later as an extension to turn the crawl space into a more proper cellar. We concluded this, following the completion of our approximately 1x1m sondage where we also reached the basement floor, a flat slab of concrete (Fig. 11). The method that was most likely used to add additional depth to the crawlspace was called underpinning; measured sections were dug out from under the stone wall at a diagonal and filled with concrete one at a time to prevent a total collapse of the wall while they extended it. This is why there were virtually no gaps between the top of the concrete and the bottom of the stones. It is also not a great way to build in an extension. Underpinning is generally used to support shifting foundations, but when installing it under a loose stonework foundation, it has the potential to significantly weaken the original structure making an already precarious construction even more susceptible to damage from erosion, weathering, and moisture infiltration. Moisture from say…a septic tank that slowly leaks its contents into the surrounding soils.

Remember that possible well and pipe in the wall I mentioned earlier? The well is actually a septic tank (OA-11B), it was briefly excavated by the Ladybugs in the last couple days of the season (Fig 12), and that iron pipe in OA-11 connects directly into it. The concrete underpinning was likely added partially to facilitate the installation of the septic system into the house.  

And just like that the season is over, the unit is backfilled and we’re left with nothing but photos, memories, plans and buckets and buckets full of burnt nails (and other artifacts but a lot of nails). Until next time!