Basement Lowering aka Basement Underpinning in Toronto and GTA Area
The one logical question that every homeowner always asks themselves before undertaking a home improvement project is “Why?”. When it comes to basement underpinning – also known as basement lowering – the answer is twofold. Whether its ceiling height that you’re looking for to turn that impractical basement into a functional space, or you’re looking to move on to bigger things and want to increase your home’s market value – no matter how you look at it, you gain.
More often than not, basement underpinning is carried out at properties with insufficient head space below ground. In order to get the project under way two things have to happen. To begin with, you, the client have to know how deep you want to dig, in other words, how high you want your ceilings to be. Next in order is official approval. To legally complete such a project you will need to run it by an architect or an engineer. This is because the nature of the work, if done without an engineer, may compromise the structural integrity of your home. How, you may ask? In the process of underpinning a basement, load bearing walls may need to be removed. To ensure that your home can support itself for years to come, walls may need to be give way to horizontal beams and steel posts. Better safe than sorry, we always say!
Please note that no project will be carried out without the required permits and stamped architectural/engineering drawings.
The process of lowering your basement is actually pretty straight forward. Before all else, some preliminary preparations have to be made, this will ensure that everything runs smoothly. The following things will be needed. An industrial size waste bin, depending on the size of your basement you might need it twice. Keep in mind that you are taking out all of your current cement flooring PLUS at least an additional foot of soil for the entire surface area of your basement. That is a lot of waste! Additionally, your furnace and/or boiler will need to be disconnected or attached to the ceiling to allow for functional use. Finally, before any soil is removed, short-term support systems need to be put in place to keep the house from deforming – this is usually done with vertical jacks and horizontal beams. As soon as these arrangements are taken care of, the conveyor belt system can be put in place to assist with soil removal.
Once the concrete and soil have been removed, we are ready to proceed with the underpinning. The specifications of your unique project will have been outlined by your engineer or architect. Work is usually carried out in 3 detached phases, ranging from two to three feet in length – the depth varies from 18 to 24 inches or more. Although the height of the underpinning depends on the desired height of the ceiling, a two inch space must be left between the newly poured concrete and the original foundation , then this gap is filled with non-shrink grout.
For home owners of semi-detached homes, “bench footings” will be mandatory for adjoining walls.
Now that your new foundation walls are in place, old plumbing can be removed, and new plumbing put in its place. You will be provided with new plumbing rough-ins that will enable you to create your desired space. At this point we will install a reliable waterproofing system to make sure your basement stays dry, it consist of internal weeping tiles , waterproofing membrane and sump pump. To get ready for the pouring of the new concrete floor we evenly place four to six inches of gravel throughout the basement. Finally, before the concrete goes in we cover your foundation wall and gravel bed with a drainage mat.
The new slab that will be poured will be reinforced and will be four to five inches thick. Once the concrete is dry, your new basement is ready to use!
To start underpinning:
- Get in touch with Aquamaster Drain Plumbing & Waterproofing Inc to book a free consultation
- We will provide you with an architect/engineer to obtain permits OR you may find one yourself
- Architect/engineer will obtain permits and will fast them according to the client’s timeline
- Set commencement date for the project