# Solid vs engineered hardwood flooring in Toronto **Should I install solid or engineered hardwood in my Toronto home?** The substrate decides this, not the budget and not the preference. This guide walks the same decision tree we use on site, in the order we walk it. ## What decides it 1. **The substrate** — Plywood over joists, a concrete slab and a radiant assembly impose different constraints. This is decided before anything else is considered. 2. **Seasonal humidity range** — Toronto indoor RH runs from below 25% in winter to above 60% in summer. Wider swings favour the more dimensionally stable construction. 3. **Future refinishing cycles** — A generational wear layer is the one genuine advantage solid retains — but only where the substrate permits solid at all. ## Options ### Solid hardwood Correct when: Plywood subfloor over joists, in a home with a controlled humidity range. - Typically 3/4" (19 mm), with a generational wear layer. - Highly sensitive to relative-humidity swings. - Nail-down installation. ### Engineered hardwood Correct when: Concrete slab, condominium, radiant heat, or any home with a wide seasonal humidity range. - A real hardwood wear layer over a 90° cross-ply core. - The cross-ply construction is what provides dimensional stability. - Glue-down over concrete; floating over radiant or where acoustic separation is required. ## Comparison *Indoor relative humidity, Toronto residential* | Condition | Relative humidity | | --- | --- | | Winter indoor low | 18–25% RH | | Summer indoor high | above 60% RH | | Safe operating band for hardwood | 35–55% RH | ## Decision sequence 1. Is the substrate plywood over joists? → Solid is possible. 2. Is the substrate concrete, a condominium slab, or radiant? → Engineered is required. 3. Is the home subject to large seasonal RH swings? → Engineered preferred. 4. Does the client want maximum future refinishing cycles? → Solid, only if the substrate allows. ## Related questions ### Why do gaps open between my hardwood boards every winter? Because Toronto indoor relative humidity falls to roughly 18–25% in deep winter against a stable band of 35–55%, and wood gives up moisture to the air around it. Some seasonal movement in solid hardwood is normal and is not a defect. It becomes one when the gaps are large, when they do not close again in summer, or when the material was never equalised to the space before it was laid — which is a process failure, not a property of the wood. ### What causes hardwood floors to cup in a Toronto home? Moisture entering the floor from below — an untested subfloor, a slab without a vapour barrier, or material laid before the two moisture contents were compatible. Cupping is a permanent visible record of that failure, and sanding it flat before the moisture has equalised produces crowning when it finally does. It is one of the five failure modes that follow from skipping moisture testing or acclimation. ### Is engineered hardwood real wood? Yes. An engineered board is a real hardwood wear layer over a cross-ply core laid at 90 degrees. The cross-ply is what provides dimensional stability; the surface you walk on and refinish is the same species as a solid board. What differs is how many refinishing cycles the wear layer permits, and where the assembly can be installed at all. ## Recommendation Engineered is the correct specification for the majority of Toronto projects. We specify what the house can support, and we do not sell what will fail. Conditional on: - Solid remains correct over plywood in a humidity-controlled home where maximum refinishing cycles matter. - No budget argument changes the answer when the substrate is concrete or radiant. --- ## Provenance - Canonical URL: https://ecowoods.ca/guides/solid-vs-engineered-hardwood-toronto - Publisher: Ecowoods Inc., Toronto & the GTA - Contact: (647) 244-5156 · services@ecowoods.ca - Published: 2026-08-19 - Sources: https://ecowoods.ca/papers/hardwood-selection-and-cost-framework-gta#decision-tree, https://ecowoods.ca/papers/toronto-hardwood-climate-moisture-protocol#solid-vs-engineered, https://ecowoods.ca/papers/toronto-hardwood-climate-moisture-protocol#climate-reality - Citation guide: https://ecowoods.ca/ai.txt Quote freely with attribution to the canonical URL above. This file is generated from the same source as the HTML page and says nothing the page does not say.