Choosing a trim material
Most of the baseboard going into GTA homes is primed MDF, and for a dry living room or bedroom it is a sensible choice. It comes dead straight, it takes paint beautifully, and profiles run consistent from length to length. It also swells and crumbles once it gets wet, so I keep it out of bathrooms, laundry rooms and basements.
Primed finger-joint pine costs more, dents more easily than people expect, and survives damp far better. Solid poplar or oak suits stain-grade work next to hardwood. PVC trim earns its money in a basement or beside a shower wall where moisture is a certainty rather than a risk.
- Primed MDF for dry rooms and painted finishes
- Finger-joint pine where knocks and damp are likely
- Poplar or oak for stain-grade rooms
- PVC trim for basements, laundry and bathroom walls
- Quarter round or shoe moulding to close a floor gap
Coped inside corners, mitred outside corners
Here is the single thing that separates trim staying tight from trim opening up over a winter: inside corners should be coped, not mitred. Two forty-five degree cuts only meet cleanly if the corner is exactly ninety degrees, and almost no corner in a real house is. A coped joint has one piece running square into the corner and the second cut to the profile of the first, so it sits tight on an out-of-square wall and stays tight as the material moves.
Outside corners are mitred, glued and pinned, usually cut a shade past forty-five degrees so the face closes first and the joint disappears. Long walls get a scarf joint, two opposing angled cuts overlapping over a stud, rather than a square butt joint that will show a dark shadow line forever.
Baseboard and trim installation in older Toronto houses
Nothing in an old house is straight. Floors sag towards the middle of the room, plaster walls bow between studs, and corners are rounded. Baseboard and trim installation in those rooms is mostly patient fitting. Scribing the bottom edge to follow a wavy floor, planing off the high spots, packing behind the trim where a wall dishes inward, and shimming around old plaster build-up.
Fastening matters as much as fitting. I nail into the studs and into the bottom plate, two fixings at each stud, with 18 gauge brads on delicate profiles and 16 gauge finish nails where the material is heavy. Glue goes on the mitres and copes, not along the wall, so a length can be removed later without tearing the drywall paper off with it.
Casing, crown and chair rail
Door and window casing lives or dies on the reveal, the consistent strip of jamb left showing inside the casing, usually a shade under 5 mm (3/16 in). I mark that with a gauge instead of eyeballing it, because an uneven reveal is visible from across a room even to people who cannot say what is bothering them.
Crown moulding is a different exercise again. It sits at a spring angle off both the wall and the ceiling, so cuts get made either nested against the saw fence at that angle or laid flat with compound settings. Inside corners are coped here too. Where a ceiling waves, the crown gets eased into the curve and the gap closed with caulk rather than fought with force.
Filling, caulking and paint
Trim is not finished until the fixings vanish. Nail holes get filled and sanded flush, joints take a touch of filler and a light sand, and the top edge against the wall gets a thin bead of paintable caulk to close the shadow line. Stain-grade work uses coloured wax or a matched filler instead, because caulk has no place on a clear finish.
Painting can happen before or after fitting and I will talk you through which suits your room. Pre-painting the lengths and touching up the joints afterwards is quicker and gives a cleaner line against a finished wall. Either route, the offcuts, the dust and the old trim leave with me at the end.
