One of our favorite types of projects to tackle is when we get hired to fabricate and install a new precast bulkhead unit.
Sometimes we are replacing an existing unit that had gradually corroded over time.
Other times we are hired to fabricate and install a new unit for someone’s home who has never had a bulkhead before.
In each case, it can be a very complicated project as there are multiple moving pieces involved.
A pre-cast bulkhead unit is an all encompassing unit where the bulkhead “top” (the portion containing the bulkhead doors) and the bulkhead “bottom” (the portion containing the stairs leading to the basement) are steel-fabricated into one solid unit vs. having separate bottom & top portions to the bulkhead system (i.e., the top portion being made out of steel and the bottom portion being made out of cement).
When installing a pre-cast unit where there has never been one in place, not only does the actual unit itself need to be fabricated and installed, but there is a series of methodology that needs to be followed in order to ensure proper installation.
Typically, this is what is involved:
– Some type of excavation takes place
– “Hole” needs to be cut into foundation in order to accommodate the new unit
– Unit is fabricated & installed
– The area that was excavated around the bulkhead has to be filled back in with soil
– An entry door has to be custom fit at the base of the bulkhead leading into the basement (unless of course you had wanted to leave this area open without a door for some reason)
– If the entry door is installed, you may or may not wish to prep & finish the interior & exterior portions as well
– Any area around the place where the bulkhead attaches to the house which needs to be “finished off” (vinyl siding that needs to be re-fit in, etc.) is finished off to provide the appearance of as seamless an install as possible
If replacing a pre-cast unit that had already been previously installed, a very similar procedure is approached, with the exception of having to cut a hole in the foundation and possibly any work around the entry door leading into the basement from the bulkhead (the condition of the existing door would most likely dictate what, if anything, is done to the door).
Assuming everything else has been correctly completed, the most important part of the install is the maintenance around the unit that has to be done as the dirt that was filled back in settles over time.
As moisture (rain/snow) falls around bulkhead, the soil that was filled back in will naturally compress, even if it is compacted as best as possible when the unit is installed.
There is an old story of a professor showing a glass jar full of rocks to his students in which he repeatedly asks if they believe the jar is full and he adds smaller stones, pebbles, sand, and finally water while mesmerizing the students as to what he may be able to possibly fit more of into the jar.
The same type of scenario is what is occurring around the newly installed bulkhead, compounding each time moisture hits the area around it, and causing the appearance of various degrees of “caving in”.
It is imperative to stay on top of this by adding extra fill when needed (perhaps saving some from the original excavation if possible).
As time goes by, eventually the dirt will reach a point where it will no longer be compacting and will be as settled as it is going to get.
Every situation is different, as soil can vary in its density even from one yard to another on the same street.
Patience may certainly be a virtue as the soil’s ultimate position around the bulkhead is achieved, but diligently staying on top of things and making sure the dirt is put back in place as it settles, will be quite helpful in expediting the process no matter how long it ends up taking. Lopco Painting
