Want a taller, more usable basement in your Kingston home? You have two main ways to get there. You can underpin the foundation, or you can build a bench footing. Both lower your floor and add headroom. However, they work very differently and cost very differently.
We have dug under plenty of homes across Frontenac County. So this guide breaks down how each method works, what it costs, and when each one makes sense. Because the right choice depends on your goals, your budget, and what is under your house.
Why homeowners lower a basement floor
Older Kingston homes often have short basements. Many sit at six or seven feet of headroom. That is too low for a finished living space, a legal apartment, or a comfortable rec room.
Lowering the floor unlocks real value. For example, you can add a basement suite, a home gym, or a proper laundry area. In short, you gain square footage without building up or out.
That said, both methods touch your foundation. So they are not simple weekend jobs. They need engineering, permits, and an experienced crew. To see how we handle this kind of work, take a look at our basement excavation services.
What is basement underpinning?
Underpinning extends your existing footings deeper into the ground. In plain terms, we dig below the current foundation in small sections. Then we pour new concrete underneath to build a deeper, stronger footing.
After the footings go lower, we can dig out the floor and pour a new slab at the new depth. The result is full-height ceilings from wall to wall. You keep every inch of floor space.
How underpinning works, step by step
- Engineering and permits. An engineer designs the sequence and the new footing.
- Sectional digging. We excavate under the foundation in short, staggered pins.
- Pour and cure. We pour concrete in each pin and let it cure before moving on.
- Dig and slab. Once the footings are deep enough, we lower the floor and pour a new slab.
Because we work in small sections, the house stays supported the whole time. However, this careful sequencing takes longer. So underpinning is the more involved of the two options.
We cover the full process in more detail in our guide to underpinning in Ontario. It is worth a read if you want the technical picture.
What is bench footing?
Bench footing takes a different path. Instead of going under the existing footing, we leave it alone. We dig down beside it and pour a new slab at a lower level. Then we build a concrete “bench” along the base of the wall.
That bench looks like a wide step running around the room. It supports the existing foundation while letting the centre of the floor sit lower. So you gain headroom in the middle of the room.
The trade-off with a bench
The catch is the bench eats into your floor space. It usually runs about a foot or two wide along every wall. For a small basement, that lost space adds up fast.
However, bench footing is faster and less risky than underpinning. Because we never disturb the original footing, the structural risk drops. So many homeowners choose it to save time and money.
Underpinning vs bench footing: cost and complexity
Cost is usually the deciding factor. Underpinning costs more because it is slower and more technical. Bench footing costs less but sacrifices floor area.
In Ontario, underpinning often runs in the range of several hundred dollars per linear foot of foundation, depending on depth and soil. Bench footing typically lands lower per foot. These are general ranges, not quotes. Your real number depends on your home, your soil, and your access.
For broader budgeting on basement projects, our breakdown of the cost to dig a basement in Kingston helps set expectations.
Quick comparison
- Headroom: Underpinning gives full height wall to wall. A bench gives height only in the centre.
- Floor space: Underpinning keeps it all. A bench reduces it.
- Cost: Underpinning is higher. A bench is lower.
- Risk: Underpinning touches the footing, so it carries more structural risk.
- Time: Underpinning takes longer because of the curing sequence.
So neither option is “better” overall. The right pick comes down to your priorities. If you want maximum usable space, underpinning wins. If you want to save money and keep things simpler, a bench may do the job.
When does basement underpinning in Kingston make sense?
Choose underpinning when floor space matters most. For example, a narrow basement cannot afford to lose a foot along every wall. In that case, the bench would shrink the room too much.
Underpinning also makes sense when you plan a legal basement suite. Rental units need consistent ceiling height across the floor. So a full-depth lowering gives you a cleaner, more usable result.
It is the stronger choice when you want to maximize resale value. A full-height basement reads as real living space, not a finished crawl. If you are weighing how to add the most value, our piece on walkouts vs egress windows pairs well with this decision.
When does bench footing make sense?
Bench footing fits tighter budgets. Because it skips the slow underpinning sequence, labour drops. So you spend less to gain usable height.
It also suits homes where the foundation is fragile or hard to work under. In those cases, leaving the original footing alone reduces risk. That can matter a lot with older masonry.
Finally, a bench works well in larger basements. When the room is wide, losing a foot of perimeter barely registers. So you get the headroom you want without missing the floor space.
The limestone factor in older Kingston homes
Kingston is the Limestone City for a reason. Many older homes sit on rubble limestone foundations. These walls are strong in compression but loose in mortar and harder to underpin cleanly.
That changes the math. Underpinning a limestone wall takes extra care, extra engineering, and sometimes extra reinforcement. So the risk and cost both climb.
In some of these homes, bench footing becomes the safer call. Because it leaves the old footing untouched, it avoids disturbing fragile stonework. However, every home is different. So we always assess the foundation in person before recommending a method.
Why local experience matters here
We have worked under Kingston-area homes for over 20 years. We know how local soil, water tables, and old foundations behave. That knowledge helps us spot problems before they become expensive surprises.
For instance, high groundwater near the lake or rivers can complicate any deep dig. So we plan drainage and shoring from the start. In short, local know-how keeps these projects safe and on budget.
Permits for underpinning and bench footing
Both methods are structural work. So you need a building permit, full stop. You also need engineered drawings stamped by a professional engineer.
In Kingston, the permit comes from City of Kingston Building Services. If your home sits in a Frontenac County township, you apply through that township’s building department instead. Please note that KFL&A Public Health no longer handles these structural permits.
We handle the coordination so you do not have to chase paperwork. Because we have filed many of these applications, we know what local inspectors want to see. So the approval process moves smoother.
Get a free quote
Not sure which method fits your basement? We can take a look and give you a straight answer. No pressure, no jargon, just honest advice from a local crew.
Call M. Riddle Excavating at 613-545-7955 or request a free quote on our basement excavation services page. We will walk your basement, talk through your goals, and lay out your real options and costs.
Frequently asked questions
Is underpinning or bench footing cheaper?
Bench footing usually costs less because it is faster and avoids working under the existing footing. Underpinning costs more but keeps all your floor space. Your final price depends on depth, soil, and foundation type, so we quote each job individually.
How much extra ceiling height can I gain?
It depends on your foundation depth and soil. Many Kingston basements gain one to three feet of headroom. We confirm the realistic target after an engineer reviews the structure and the dig depth.
Do I need a permit to lower my basement floor?
Yes. Both underpinning and bench footing are structural work and require a building permit plus engineered drawings. In the city, that goes through City of Kingston Building Services. In the townships, you apply through the local township building department.
Is underpinning safe for an old limestone foundation?
It can be, but it needs extra care and engineering. Rubble limestone walls are more delicate to work under. In some cases a bench is the safer choice, so we always assess the foundation before recommending a method.
How long does a basement lowering project take?
Bench footing is faster, often a few weeks. Underpinning takes longer because each section must cure before the next dig. Timelines vary with size, access, and weather, so we give you a schedule with your quote.