It is loud, and the loud days are predictable
Breaking out a slab and excavating are the two noisy stages. We will tell you which days those are so you can plan around them rather than discover them.
How we work
What actually happens, in order
Eight stages. The order is not a preference — the permit, the inspections and the concrete are all tied to it.
- Stages
- Eight
- Longest one
- The sequenced pours
- You get back
- Bare, level, drained concrete
The eight stages, in order
Nothing here can be swapped around. The permit, the inspections and the curing time all fix the sequence.
Site visit and measurements
We measure slab to underside of joist in several places, not one — basements are rarely level. We look at the wall construction, where the furnace, water heater, panel and stack sit, whether the buried drain can be located, and how a machine or a barrow would actually reach the back of the house. That last one moves the price more than anything else on the list.
A straight answer about what is possible
Before drawings, before quotes. Sometimes the answer is that the depth you want is not available because of where the drain runs. Sometimes it is that benching gets you what you actually need for considerably less. It is much cheaper to hear that now.
Structural drawings
A qualified designer or engineer prepares drawings for your house: section widths and their order, the new bearing depth, reinforcement, which walls are underpinned and which are benched, and the lintel over any new opening. The drawings are what the job is built to.
Building permit
The application goes to the City with the drawings. Who submits it and who schedules the inspections is agreed in writing before work starts, so there is no confusion about it later.
Protect, disconnect, break out
Dust separation goes up and the route the material takes through the house gets protected. Services in the way are capped or relocated. Then the old slab is broken out and removed.
Underpin or bench, in sequence
Sections are dug, formed, reinforced and poured in their numbered order, with curing time between rounds. Underpinned sections are dry-packed tight to the existing footing. This is the longest stage and it cannot be compressed.
Drainage, barrier, slab
The middle of the floor comes down to the new subgrade. New weeping tile at the new footing level in clear stone, the sump pit and pump, the vapour barrier lapped and turned up the wall, then the concrete.
Inspections and handover
City inspections at the stages the permit calls for. What you get back is a bare, level, dry concrete floor with the drainage in and the sump running — ready for the framing trade.
On the day
Noisy, dusty, and every barrow of spoil and concrete travels a route through your house that we protect first.
What it is like to have this done to your house
Four things nobody enjoys hearing at quoting stage and everybody would rather have known.
Everything leaves through your house
Unless there is a walkout or a machine can reach the back, every barrow of spoil and every barrow of concrete travels your route. Protecting it properly is part of the job, not an extra.
There will be a period with no basement
Between the slab coming out and the new one going in, that space is a work site. Anything stored down there needs to be gone before we start.
Curing time is not idle time
There are days with no visible progress because concrete is doing what it needs to do. A schedule without them is a schedule that is not being followed.
The survey that saves the project
Almost every underpinning job that goes badly, goes badly for one of two reasons: something under the floor was not found before the work started, or the access was never properly thought through.
The buried drain line is the usual culprit. It runs under the slab to the street, and its depth is fixed. If the new floor level would sit below it, the floor cannot go there — or the drain has to be re-run, which is a substantial piece of work with its own permit implications. Finding that out on day one costs an hour. Finding it out on day fifteen costs the schedule.
The second is the material route. Spoil and concrete both move by hand more often than people expect on Mississauga's narrower older lots. It is frequently the difference between two quotes for the same basement.
Eight questions worth asking any contractor
Ask us these too. If an answer is vague, that is information.
Are you underpinning or benching, and why that one for my basement?
There should be a reason specific to your room, not a general preference.
How wide are the sections and what is the sequence?
It should be on the drawings. If nobody can tell you, the drawings are not being followed.
Who prepares the drawings and who pulls the permit?
And which of those costs are in this quote.
What is the new floor assembly?
Weeping tile, stone, sump, vapour barrier, slab. If drainage is not mentioned, ask why not.
How does material get in and out of the house?
Their answer tells you whether they have looked properly.
Have you found the buried drain, and how low can the floor actually go?
A number given without this is a number that can change.
What state is the basement in when you leave?
Bare concrete, or something further along. This is the biggest reason quotes differ.
What happens if the dig finds something unexpected?
Old fill, a buried footing, water. How that is priced should be agreed before it happens, not after.
Start with stage one
A measurement and an honest answer about what is possible. Nothing is committed at that point, by either of us.