Baseboards are one of the most visible finishing touches in any room — and one of the most achievable DIY projects for GTA homeowners. A standard 12-by-12 foot room has roughly 48 linear feet of baseboard. DIY materials run $60–$120 in MDF or up to $300 in solid wood; a pro charges $150–$300 in labour for the same room. With a miter saw, a finish nailer, and an afternoon, you can match or beat professional results — if you understand inside corners.
Installing new flooring first? Read our guides on installing laminate flooring and installing vinyl plank flooring — baseboards go on after the floor is down.
2026 GTA Baseboard Costs and Supplies
🛒 Materials You'll Need
- MDF baseboard (colonial or craftsman profile): $1.00–$2.50/lf at big-box
- Solid wood baseboard (pine/poplar): $3.00–$6.00/lf
- 2" finish nails (15-gauge or 16-gauge): $12–$18/box
- Paintable latex caulk: $6–$10/tube
- Wood filler / lightweight spackle: $8–$15/tub
- Primer + paint: $20–$35 (if not already on hand)
- Construction adhesive (optional): $6–$10/tube
🔧 Tools You'll Need
- Miter saw (compound miter preferred): own or borrow
- Finish nailer (pneumatic or cordless): rent ~$40/day in GTA
- Air compressor (if renting pneumatic nailer): often bundled
- Tape measure + pencil
- Digital angle finder or sliding bevel gauge
- Coping saw (for coped inside corners)
- Hammer and nail set (backup for hand-nailing)
- Utility knife and putty knife
| Scenario | Materials | Labour | Total (CAD) |
|---|---|---|---|
| DIY — MDF baseboard | $48–$120 (48 lf × $1–$2.50) | $40 nailer rental | $88–$160 |
| DIY — solid wood baseboard | $144–$288 (48 lf × $3–$6) | $40 nailer rental | $184–$328 |
| Pro-installed (labour only) | $48–$288 (materials at your choice) | $96–$192 ($2–$4/lf) | $144–$480 |
💡 MDF vs. Solid Wood: Which Profile?
MDF baseboards are the standard choice for painted applications — they are dimensionally stable, take paint well, and cost 60–70% less than solid wood. Colonial profile (the S-curved classic) is available everywhere; craftsman profile (flat with a small cap rail) suits modern and semi-modern homes. Use solid wood (pine, poplar) only if you plan to stain rather than paint — MDF cannot be stained. Buy 10–15% extra to account for waste on miter cuts and mistakes.
Step 1: Measure the Room
Measure Every Wall and Mark the Studs
Measure each wall at baseboard height and add up the total linear footage. For a 12-by-12 foot room, the perimeter is 48 linear feet — buy 53–55 lf to account for waste. Use a stud finder to mark every stud location on the wall at baseboard height, then transfer those marks lightly in pencil to the wall surface so you can see them when nailing. In most GTA homes, studs are on 16-inch centres, giving you 3 nailing points per 4-foot section. Mark any areas with no studs within reach — you will use construction adhesive there instead of relying on nails alone.
Step 2: Cut the Angles — Miter for Outside, Cope for Inside
Outside Corners: Two 45-Degree Miters
Outside corners get a standard 45-degree miter on each piece — one piece cut left at 45 degrees, the other right. Before cutting, check the actual corner angle with a digital angle finder. If the wall reads 91 degrees instead of 90, split the difference: cut each piece at 45.5 degrees. Apply wood glue to the miter joint in addition to nails — the glue prevents the joint from opening as the trim expands and contracts seasonally. Hold the joint tight with painter's tape while the glue sets, then shoot two finish nails through the corner to lock it.
Inside Corners: Cope, Don't Miter
Coping is the professional method for inside corners — and the right one for virtually every GTA home, where walls are rarely a perfect 90 degrees. The technique: run the first piece of baseboard flat into the corner, cut square at the wall. For the second piece, cut a 45-degree miter on the end to reveal the profile shape, then use a coping saw to cut along that revealed profile line at approximately 90 degrees to the back of the board. The coped end slides over the face of the first piece. Test fit, trim as needed with the coping saw or a rasp, until the joint sits tight. Coped joints stay tight as the wood moves; mitered inside corners open up.
⚠️ Scarf Joints for Long Walls
If a wall is longer than your longest baseboard piece (typically 8 or 12 feet), you need a scarf joint to join two pieces end-to-end. Cut both ends at 45 degrees in the same direction so they overlap like a slanted seam — never butt two pieces square end-to-end on a long wall. Position a scarf joint directly over a stud so you can nail both pieces into solid wood. Apply a thin bead of wood glue to the scarf before nailing.
Step 3: Nail in Place
Shoot Nails Into Studs — Two Per Stud
Hold each baseboard piece firmly against the wall and floor. Shoot one 2-inch finish nail high into each stud location (to catch the wall framing behind the drywall) and one nail low into the wall's bottom plate. Set the nailer depth so nail heads sit just below the surface — you'll fill them in the next step. Between studs, if the board bows away from the wall, apply a bead of construction adhesive to the back of the board before pressing it flat, then tack with a nail into the drywall only as a temporary clamp while the adhesive cures. Don't rely on drywall-only nails for structural hold.
Step 4: Fill Nail Holes and Caulk
Fill, Sand, Then Caulk the Top Edge
Fill all nail holes with lightweight spackle or wood filler using a putty knife — overfill slightly, let dry completely (20–40 minutes for lightweight spackle), then sand flush with 120-grit sandpaper. Wipe off dust. Next, run a thin bead of paintable latex caulk along the top edge of the baseboard where it meets the wall. Smooth immediately with a wet finger in one continuous motion — don't try to re-work caulk that has begun to skin over. The caulk line hides any gap between the baseboard and an imperfectly flat wall, and it paints over cleanly. Also caulk inside corners after installing if any gap remains after coping.
Step 5: Paint
Prime Filled Areas, Then Apply Two Coats
If you pre-painted the boards before installation (recommended), you only need to touch up: apply a thin coat of primer to the filled nail holes and any bare MDF edges, let dry, then paint the touch-up areas with a small brush. If painting after installation: prime the entire baseboard first (especially critical for MDF — bare MDF will soak up paint and look rough without primer), let dry, lightly sand with 180-grit, then apply two coats of semi-gloss or satin trim paint with a 2-inch angled sash brush. Semi-gloss is the traditional choice for trim in the GTA; satin is increasingly popular for a less shiny look. Mask the wall above the caulk line and the floor below for clean edges.
💡 Pro Tip: Pre-Paint Before Installing
Prime and paint the flat faces and edges of all baseboard pieces before installation — working on sawhorses is faster and produces cleaner coverage than painting in place. Leave the backs and the top and bottom edges bare. After installation, fill nail holes and caulk, then touch up with a brush. This two-phase approach is the standard professional method and cuts painting time by 30–40% compared to painting all trim in place.
Frequently Asked Questions: Installing Baseboards in the GTA
❓ How do I handle inside vs. outside corners?
Inside corners get coped joints — one piece runs flat into the corner, the second is coped to overlap the first's profile. This handles out-of-square walls that are the norm in most GTA homes. Outside corners get two 45-degree miters that meet at the corner's point. Check the actual angle with a digital finder before cutting — it's rarely a perfect 90.
❓ Should I cope or miter inside corners?
Cope. Mitered inside corners look fine initially but open up as wood moves with seasonal humidity changes — a real issue in GTA homes that swing between winter dry heat and summer humidity. Coped joints stay tight. The cope takes practice on the first joint or two; by the third joint it's fast.
❓ What size nail for baseboard installation?
Use 2-inch (15-gauge or 16-gauge) finish nails. One nail high into each stud, one nail low into the bottom plate. Between studs where no framing is reachable, use construction adhesive on the back of the board — drywall-only nails don't provide reliable hold for trim under seasonal stress.
❓ Do I paint before or after installing baseboards?
Paint the faces and edges before installation, then touch up nail holes and caulk lines after. Pre-painting flat on sawhorses is faster and cleaner. You'll need primer on MDF or bare wood sections after filling nail holes — don't skip the primer or the paint won't adhere evenly over filler.
❓ How do I handle out-of-square corners?
Use a digital angle finder to read the actual corner angle before cutting. For outside corners, divide the actual angle by two to get your miter cut. For inside corners, cope the second piece — coping is forgiving of imperfect angles in a way that mitering is not. Any remaining gap after installation gets filled with paintable latex caulk. Caulk is the professional finisher that makes imperfect angles disappear.