How do I prepare wood trim for repainting in an older Ottawa home?

Wood trim prep in older Ottawa homes is a whole different ball game compared to newer builds. Many houses in Sandy Hill, the Glebe, Westboro, and Rockcliffe Park have original wood trim from the early 1900s -- thick baseboards, ornate door casings, crown mouldings with beautiful profiles. The good news is that old-growth wood trim is almost always worth saving. The prep just needs to be thorough.

Step 1: Test for Lead Paint

This is non-negotiable in any Ottawa home built before 1978. Lead-based paint was common and layers of it are almost certainly present under existing coatings on pre-1960s trim. Pick up a 3M LeadCheck swab kit ($15-$25 for a 2-pack) at any Ottawa hardware store. If the swab turns red or pink, you have lead paint.

For lead-positive trim:

• Do not dry sand. Lead dust is a serious health hazard, particularly for children.


• Use chemical strippers (Citristrip is widely available in Ottawa for about $25-$35 per quart) or wet-sanding methods.


• Contain the work area with plastic sheeting and use a HEPA vacuum for cleanup.


• Ontario has guidelines under the Occupational Health and Safety Act for lead paint handling. Professional painters in Ottawa should carry WSIB coverage and follow safe work practices for lead abatement.

Step 2: Clean the Trim Thoroughly

Decades of built-up grime, cooking grease, and cleaning product residue sit on that trim. TSP (trisodium phosphate) mixed at about 30 grams per litre of warm water is the standard. Wipe down all surfaces with a sponge, then rinse with clean water. A box of TSP runs about $8-$12 at Canadian Tire or Home Hardware. Let the trim dry completely -- at least 24 hours in Ottawa's cooler months when indoor humidity can linger.

Step 3: Scrape and Sand

Using a quality carbide scraper (a Bahco or Hyde scraper, $15-$30), remove any loose, peeling, or alligatored paint. Don't try to take it all off -- just remove what's failing. Focus on:

• Window casings -- these take the most abuse from condensation cycles in Ottawa winters. The freeze-thaw at -25 to -30 degrees Celsius creates moisture behind the paint film.
• Baseboards near exterior walls -- moisture migration causes peeling here more than anywhere else.
• Door casings in high-traffic areas -- scuff marks and chips need to be feathered smooth.

After scraping, sand the entire trim surface with 150-grit sandpaper to create tooth. For detailed profiles and mouldings, use sanding sponges that conform to curves. Finish with 220-grit for a smooth base.

Step 4: Fill and Repair

Older trim almost always has:

• Nail holes from decades of re-nailing


• Gaps between trim and wall from the house settling over 80-120 years


• Dents and gouges from furniture, pets, and daily life

Use DAP Plastic Wood-X or similar wood filler ($8-$12) for holes and dents. For gaps, use paintable acrylic caulk (about $5-$7 per tube). Apply caulk with a caulking gun and smooth with a damp finger. Let filler dry fully and sand smooth with 220-grit.

Step 5: Prime

This is where the longevity of your repaint is determined. On old wood trim with multiple paint layers, use a high-adhesion bonding primer like Zinsser BIN (shellac-based, about $28-$35 per quart in Ottawa) or STIX by Insl-X. These primers:

• Lock down any remaining old coatings
• Block tannin bleed from old wood (common in oak and fir trim)
• Provide a uniform base for your topcoat

Apply with a high-quality angled brush (a Wooster Shortcut or Purdy XL are favourites among Ottawa painters, $12-$18 each). Don't cheap out here -- brush quality directly affects the smoothness of trim work.

Step 6: Final Sand and Topcoat

After primer dries (1 hour for shellac-based in good conditions), sand lightly with 220-grit, tack off, and apply your first topcoat. For trim, most Ottawa painters prefer a semi-gloss or satin alkyd-modified latex like Benjamin Moore Advance ($65-$75 per gallon). It self-levels beautifully and cures to a hard, washable surface -- important in a city where road salt and slush get tracked indoors six months of the year.

Two topcoats with a light 320-grit sand between them gives you a factory-smooth finish.

Professional Cost Expectations

Professional trim repainting in an older Ottawa home typically runs $3.50-$6.50 per linear foot depending on the condition and detail of the mouldings. A full house of trim (baseboards, casings, crown) in a typical Glebe or Alta Vista home might run $2,500-$5,000. Heritage homes with extensive ornamental woodwork can go higher.

For experienced painters who specialize in older Ottawa homes, check the Ottawa Construction Network directory -- they list local contractors by specialty. And for more prep and painting guidance, Ottawa Paint Contractors' Paint IQ is here to help.