Site Survey is Conducted:
A site survey is conducted by a design technician or crew leader to determine where to pile castings (the dirt that comes out of the excavation pit), where we can pile necessary construction materials such as gravel and where we can safely park trailers, machinery, clean fill bins and the like. Sometimes we require permission from a neighbor to pile castings on their property to facilitate our work. It is at this time that we decide how the site is to be protected, where we need to lay plywood to protect the ground and how the site is managed during the course of the work to facilitate access into the home by the homeowner and crew members, if required.

Locates and Building Permits:
We call for locates of gas and electric lines and apply for a building permit, if required, and a start week is designated. (We say start week since the timing of exterior work at other customer sites depends on the weather).

Excavation Site Prep:
Site prep begins. One of our excavators is dropped on site, if the area is machine accessible. Ground protection boards and shoring sections are dropped on site, if necessary and excavation commences.

Exterior Excavation is Completed:
Excavation is completed either by hand or by machine. Shallow digs require no shoring and no slope to the excavated area. Deep digs are either sloped or shored as per Ontario Department of Labour guidelines for safety.

Foundation Wall Exposed:
Once the foundation wall and footing are exposed, they are scraped or wire brushed and any visible cracks are filled with hydraulic cement. This is your 1st line of defense to prevent water from penetrating your foundation walls.

Liquid Rubber is Applied:
Then, liquid rubber is applied to the wall which seals every inch of the foundation wall. This is your second line of defense and the job now meets code.

Dimpled Sheet Air-Gap Membrane:
But, we like redundancy, so we also apply a dimpled sheet air-gap membrane which not only provides you with a third line of defense, but also creates a hydrostatic pressure relief which is how water forces its way through your foundation wall in the first place.

Note: This may seem excessive, but our motto is “do it once, do it well”. All of our exterior systems far exceed what is required by the building code but we are also providing a warranty 10 times the length of that which is provided by the new home warranty program!

Weeping Tile Installed:
New weeping tile is then installed. The best approved product presently available for typical residential applications is 4" corrugated pipe with a filter fabric surround. The pipe has slits around the perimeter running the full length of the pipe to admit water, and a filter fabric "sock" to inhibit the ingress of fining's or silt. This is important to know since the footing drain is the most important part of any system. The biggest deficiency of a corrugated flexible pipe is than A) It can be crushed during the work, and B) Since it is stored in a roll, it has a "memory" and therefore has a tendency to ride up over and above the footing.

Therefore, when Basement Technologies® installs weeping tile we often use weights and/or pegs to hold it in place and we ensure, prior to the installation of gravel, that the weeping tile is where we want it to be. Even a small rise in any section of a 4" weeping tile can reduce the effective diameter and so we pay special attention to this to maximize its drainage capacity.

Above Grade Clean out Installed (Where Permitted):
Once the weeping tile is in place we install an above grade clean out. This is something that we started doing about 10 years ago to provide above grade access to the weeping tile to facilitate monitoring and maintenance. This provides access to video the weeping tile system or to provide a power flush, thus increasing its life and avoiding excavation in the future.

NOTE: This service install is not permitted in the Greater Hamilton Area.

Gravel Put in Place:
Gravel is then installed over the weeping tile. The Ontario Building Code specifies "not less than 5 and 7/8" of gravel on top and beside the weeping tile (or about 1/2 a foot on top and beside). When calculating our gravel for delivery, we purchase 2 cubic feet per linear foot of weeping tile for our system. This is roughly double that which is required by the building code. Since the purpose of the gravel is to facilitate the functioning of the weeping tile, and as we stated, the weeping tile is the most important component of the system, it makes sense to spend a bit more here while the house foundation is exposed to provide a more robust system.

Filter Fabric Installed:
Filter fabric is then installed over the gravel to prevent silting of the gravel. Since most of the water that enters the gravel drainage layer, and then the weeping tile, comes from above, it makes sense that the water will bring dirt and silt with it as it percolates down through the soil. Without the filter fabric the spaces between the gravel that provide the drainage to the weeping tile get filled up with dirt. At that point there is little difference between the gravel on top of your weeping tile and the dirt on top of the gravel and it is no longer serving its purpose. Installing filter fabric prevents this and is another way we go the distance to increase the life expectancy of your exterior system.

Building Inspection Conducted:
A building inspection is conducted, if required, by a municipal building inspector. The building inspector will ensure that all of our work meets code as well as checking to ensure that we have the correct licenses. Since our procedures exceed that which is required by the Ontario Building Code, this is ends up being quick and painless for us while providing you with peace of mind knowing everything was done correctly before it is all buried under ground.

Backfilling & Cleanup:
Backfilling and cleanup is commenced. Sometimes we backfill with gravel and remove all of the dirt from the property (design technician may specify gravel backfill for various reasons including removal of soil pressure, prevention of settling, or to reduce ponding or frost affects).

Removal of Extra Dirt:
Removal of extra dirt if required. It stands to reason that if we are installing a quantity of gravel over top of your weeping tile, that gravel will displace a similar quantity of soil. Unless the grade is too low next to the home prior to excavation, all of this dirt will need to be removed. Our default practice is to mound the dirt for natural settlement. Since we create soil voids during excavation, the dirt we place back in the trench is more voluminous. A mound will allow for grade to return close to the original following settlement. It is impossible to calculate the exact settlement following excavation. Homeowners should plan to do some landscaping and final grading following settlement. Basement Technologies® offers one free return visit to either bring more fill back to the site or to take additional fill away but of course only fill relating to our work.

Final Cleaning:
Final cleanup is completed and the driveway is power washed if required. Our Basement Technologies® crew leader will then go around the entire home with you to ensure everything is in good working order and final sign-off is completed.