Choosing between them, on the facts.

What is the best flooring for a basement over concrete in Canada?

For a basement the material has to tolerate a slab that will always carry some moisture. Solid hardwood is out: the guidelines say solid wood should not go below grade unless the manufacturer says otherwise.[1] Engineered wood and rigid-core vinyl plank are the two that are built for it.

The guidelines put engineered wood flooring as installable above, on, or below grade.[1] Vinyl plank is the other common answer because the plank itself is unaffected by water, though what happens under it still matters: see what happens when vinyl gets wet underneath.

If the basement has flooded before, that changes the order of work rather than the choice of floor. The slab gets tested, the reason it flooded gets dealt with, and only then does a floor go down. A floor installed over an unresolved water problem fails, whatever it is made of.

Engineered vs solid hardwood: which lasts in a Southern Ontario winter?

Engineered is the more stable of the two through an Ontario heating season, because its cross-layered construction resists the shrinking and swelling that opens gaps in solid boards. Solid wood can be sanded and refinished more times over its life. Neither is simply better; they fail and last in different ways.

Cost is deliberately not in that table. It moves with species, grade, width and what your subfloor needs, and a figure printed here would be wrong for your house. The solid and engineered pages have what each one needs from the room.

Vinyl plank vs laminate: which one, and which for a basement?

For a basement or any room where water is a realistic risk, vinyl plank is the safer of the two, because its core does not swell when wet the way a fibreboard-cored laminate does. Laminate's surface is generally the harder wearing of the two. Both are floating floors and both need the same flat base.

The claim to be careful with is "waterproof". It describes the plank, not the floor assembly. See the question about water getting underneath on the squeaks and cupping guide.

What is the best flooring for radiant heat?

Wood can go over radiant heat, but the system has to be run within limits, and those limits are documented. The guidelines cite ASHRAE that a floor surface temperature giving optimal comfort for most people lies somewhere between 70 and 80°F, and require that the wood floor surface temperature vary no more than 3°F at any point.[1]

Two more requirements worth knowing before anybody starts. The subfloor surface temperature should not exceed 80°F at the time of installation.[1] And on vapour control the guidelines are specific: do not use asphalt- or bitumen-type vapor retarders over radiant heat systems, while a class II vapour retarder belongs over a wood subfloor and below the flooring in the relevant case.[1]

The system should also be fully operational, regardless of season, for a minimum of 5 days before the flooring is delivered.[1] Not every engineered product suits it either: hickory, beech and maple wear layers are named as not normally best suited over radiant heat unless the manufacturer says otherwise.[1] The guidelines also say the builder, the system's design engineer and its installer should all be told what floor covering is going over it.[1] In practice that conversation is the one that gets skipped, and it is the one that prevents the failure.

What is the best flooring for dogs, for nails and accidents?

The two things that matter for dogs are scratch resistance and how the floor handles a puddle that is not found for an hour. That combination points at rigid vinyl plank or a laminate rated for wet areas, rather than a soft species of solid wood with a thin site-applied finish.

Max's take: the finish takes the scratches, not the wood, so the finish is what to ask about. A harder factory finish on an engineered board holds up better to claws than a soft one, whatever the species underneath. On solid wood, expect the traffic lanes to show first.

The one thing the guidelines are firm about is not the material but the cleaning: spills get wiped immediately to prevent damage from standing liquid.[1]

What is the best flooring for a kitchen, and can it run into the living room?

Yes, running one floor from the kitchen through the living room is normal now and it makes both rooms look bigger. The kitchen is the wet-risk room, so the material is chosen for the kitchen and then carried through, rather than the other way round.

The detail that decides the job is the cabinets. Whether the floor runs under them or stops at them changes the order of work and what happens if a cabinet ever comes out. See flooring before or after kitchen cabinets.

What is the best flooring for a bathroom that is not tile?

Rigid-core vinyl plank or sheet vinyl are the realistic non-tile answers, because a bathroom floor gets standing water at the tub and the toilet. Wood, solid or engineered, is the wrong choice in a full bathroom for the same reason wood is the wrong choice in a laundry.

In a bathroom the perimeter and the fixture penetrations matter more than the plank does. Water reaches the subfloor at the edges, not through the middle of a board.

Wide plank vs narrow plank: is wide plank better?

Wide plank looks calmer because there are fewer seams, and it is the current preference in most Ontario houses. It is not more stable. A wider solid board moves more across its width for the same change in humidity, so wide plank makes the humidity range in the guidelines matter more, not less.

That is the main reason wide plank is so often engineered rather than solid. If you want wide boards in a house that swings from 20% humidity in February to humid in July, engineered construction is doing real work for you.

Do dark floors make a room look smaller, and do they show more dirt?

Dark floors show dust, pet hair and footprints more than mid-tone floors, and they show fine scratches more because a scratch exposes lighter wood underneath. On room size, a dark floor makes a bright room feel more contained; in a room with little natural light it will read as smaller.

Max's take: mid-tone floors are the ones people stay happy with. The extremes, very dark and very pale, both show everything, just different things. This is a preference, not a rule, and it is worth looking at samples in your own light, which is the entire reason the samples come to the house.

Matte vs satin floor finish: which hides more?

Matte hides more. A lower-sheen finish scatters light instead of reflecting it, so it disguises fine scratches, dust and small imperfections in the floor underneath. Higher gloss reflects, which makes a floor look richer and shows every mark. Neither is more durable by virtue of its sheen.

Durability comes from the finish chemistry and how many coats went on, not from how shiny it is. Ask what the finish is and how many coats, not just the sheen name, because sheen names are not consistent between manufacturers.

What is the difference between luxury vinyl plank and ordinary vinyl?

Ordinary vinyl is a thin flexible sheet or tile that is glued down and follows every contour of the subfloor. Luxury vinyl plank is a thicker rigid or semi-rigid plank, usually with a click-lock edge, a printed and embossed wear surface and a separate wear layer over it.

The practical differences: LVP floats rather than glues, hides small subfloor variation better than sheet vinyl but is less forgiving of large ones, and comes with a stated wear layer thickness you can compare between products. Ask for that number in mils, because it is the one specification that separates a cheap plank from a good one.