Most Ottawa neighborhoods we love are full. Adding to the home you already own usually costs less than buying a bigger one — and lets you stay where you want to be.
50–150 sq ft additions extending an existing room (usually kitchen, dining, or primary bedroom). Often no foundation work — cantilevered or sister-footed.
Typical: $35K–$80K · 6–10 weeks
200–800 sq ft additions with full foundation. Family room, master suite, mudroom, expanded kitchen. Roof tied into the existing structure.
Typical: $90K–$320K · 4–6 months
Full or partial second-floor adds over an existing bungalow. Structural review, sometimes foundation underpinning. Typically 600–1,200 sq ft added.
Typical: $250K–$450K · 6–8 months
Add headroom and usable square footage to an existing attic. Shed, gable, and eyebrow styles. Lots of light + a bit more room.
Typical: $30K–$80K · 4–8 weeks
Attached single or double garage adds, with or without bonus room above. Including footings, foundation, framing, electrical, finish.
Typical: $60K–$160K · 8–14 weeks
Addition + interior renovation done together. Lower total cost than doing them in phases because the trades and permits are combined.
Typical: $150K–$500K · 5–7 months
For bump-outs, single-storey adds, and dormers, life keeps going. We seal the work zone with poly + zippered doors, run separate HVAC, and keep dust out of the rest of the house.
For full second-storey adds with roof removal, we usually recommend 4–6 weeks of short-term housing for the active framing phase. Your PM will give you a candid call based on your specific scope.
Ottawa typical: ~70% of project cost recouped at resale.
But: if you stay 5+ years, the "cost" is closer to zero because the addition doubles as your housing upgrade.
And: if you can avoid moving, you save 5% land transfer + 5% commission + the headache of selling.