Basement Lowering & Underpinning · Woodstock

Basement Lowering and Underpinning in Woodstock

If you have to duck in your basement, no finish will make it a room. Lowering the floor is a structural job with an engineer and a permit, and it is often the only real fix in an older house.

A lot of older Woodstock houses were built over a cellar that was never meant to be lived in. The ceiling is low to begin with, and once you account for the main beam, the ductwork and the drain lines, there may be only a narrow strip of the basement where an adult can stand up straight. Finish that and you get a nicely drywalled space nobody wants to use.

There are only a few ways to get height. You can raise the ceiling by moving what hangs below the joists. You can lower the floor. Or you can do both. Lowering the floor is the big one.

First, see if rerouting is enough

Before anyone talks about digging, check what is stealing the height. A main trunk duct can sometimes be replaced with lower-profile ducting or moved to the edge of the room. Drain lines can sometimes be rerun. Old wiring and pipes stapled under the joists can go up between them. A steel beam can occasionally replace a deep built-up wood beam, though that is structural work too. If that gets you to a usable height, it is much cheaper than lowering the floor.

Bench footing

A bench footing lowers the floor inside the room but stops short of the existing footings. The new floor is dug down, and a concrete ledge — the bench — is poured along the base of the walls to protect the soil supporting the old footing. You lose some floor area around the edges, often a usable ledge rather than wasted space. It is less invasive than underpinning and usually less expensive, but it does not suit every foundation and it has to be designed by someone qualified.

Full underpinning

Underpinning extends the foundation walls downward so the whole floor can be lowered wall to wall. The work is done in short sections, in a set sequence, so the house is always supported. Each section is dug under the existing footing, formed and poured, and allowed to cure before the next section is opened. Then the old floor comes out, the ground is dug down, new drainage and a new slab go in.

It is slow, loud and dusty. It needs an engineer's design, a building permit, inspections, and a crew that has done it before. Done properly, it turns a cellar into a full-height basement.

What gets looked at before anyone quotes

• The foundation type. Stone, rubble, brick, block or poured concrete. Stone and rubble walls are common under the older houses in Old North and downtown, and they change how the work is designed.
• The soil and the water table. How the ground behaves when it is dug, and whether water shows up. This is part of the engineer's work, not a guess.
• The drains. Lowering the floor can put the new floor below the main drain, which means the drain gets lowered too, or a pump goes in.
• The neighbours. On a narrow downtown lot with a house close beside yours, the design has to account for the foundation next door.
• Access. Every bucket of soil comes out and every yard of concrete goes in. A side yard, a basement window that can be opened up, or a conveyor route makes a real difference to the schedule and the cost.
• The furnace, water heater and stairs. They are in the way, and the stairs will need a new bottom step or a longer run once the floor drops.

Where this makes sense in Woodstock

Mostly under the older brick houses north of Dundas and around the downtown core, and in older houses in the towns and villages around Woodstock — Ingersoll, Tavistock, Embro and Beachville all have their share of century homes on low cellars. These are often solid houses on good lots, and lowering the basement is what makes the space worth finishing, or makes a secondary unit possible at all.

It rarely makes sense under the post-war bungalows or anything newer, where the basement is already close to full height. If the height problem there is a duct or a beam, fix the duct or the beam.

Permits, engineering and who does what

Underpinning and lowering a basement floor are structural work under Ontario's Building Code and need a building permit. Inside the city, that comes through the City of Woodstock; outside it, from your town or township. The design comes from a qualified engineer, not from a contractor's judgement, and the contractor builds to those drawings with inspections along the way. Get proof of liability insurance and WSIB coverage before anyone digs under your house.

What we will tell you that you may not want to hear

This is expensive, and the finishing still comes after it. For some houses the numbers work, especially when the lowered basement becomes a unit or a full living floor. For others, a carefully planned finish that works with the height you have — or leaving the cellar as storage — is the better use of the money. You will get both numbers so you can decide.

Frequently asked questions

Serving Woodstock and surrounding areas. Contact us for a no-obligation quote specific to your property.