How to measure for flooring
Measure each room separately in feet — length × width — and add them together. Include closets and pantries; flooring is cheap compared to a second trip. For L-shaped rooms, split into two rectangles. For stairs, count each tread and riser: a standard tread is about 1.5 sq ft, a riser about 1 sq ft — or measure the staircase footprint and multiply by 2.5 as a rough factor.
Measure to the wall, not the baseboard — you'll remove or undercut baseboards during install. And measure twice: flooring has the highest "oops" rate of any material because rooms are never as rectangular as they look.
Waste factors that match reality
- 7%: simple rectangular rooms, experienced installer, straight lay. The floor, not the ceiling, of waste planning.
- 10%: the standard. Normal rooms with a few doorways and angles.
- 15%: tile (cuts can't be reused), diagonal layouts, rooms with bump-outs and fireplaces.
- 20%: herringbone, chevron, or complex patterns — half your cuts are scrap by design.
Then buy one or two extra boxes beyond the waste calculation and store them. Manufacturers discontinue colors constantly; in three years, your exact floor won't exist. Future repairs depend on that closet stash.
Installation essentials
- Acclimate everything. Hardwood and laminate need 48–72 hours in the install room. Skipping this causes gapping or buckling with seasonal humidity swings.
- Flat subfloor. Most floating floors need flatness within 3/16" over 10 feet. High spots telegraph; low spots flex and break click-locks.
- Expansion gaps. Leave ¼–½" at all walls for floating floors. It gets covered by baseboard — skipping it causes buckling.
- Stagger joints at least 6–8 inches (12" for wide plank). H-joints — seams lining up in a pattern — scream amateur.
- Transitions: plan T-moldings at doorways between rooms and reducers where flooring meets different heights. Buy them with the floor so colors match.
What affects flooring cost
Materials: laminate $1–$4/sq ft, luxury vinyl plank $2–$6, engineered hardwood $4–$10, solid hardwood $6–$14, tile $2–$8 (plus thinset and grout). Professional installation adds $3–$8/sq ft depending on material and region — tile and hardwood at the top end.
The quote killers are subfloor prep (leveling compound, plywood overlay), old floor removal ($1–$3/sq ft), and moving furniture. A 400 sq ft LVP job might be $2,000 in materials but $4,500 installed once demo, prep, and trim are itemized — always compare line items.
Common flooring mistakes to avoid
- Skipping acclimation. Hardwood and laminate need 48–72 hours in the room before install. Skipping this is how you get gaps in winter and buckling in summer.
- No expansion gap. Floating floors expand — leave ¼" around every wall and fixed object. The baseboard hides it; a buckled floor does not.
- Installing over an uneven subfloor. More than 3/16" of variation over 10 feet telegraphs through LVP and cracks tile. Level first; it's the cheapest insurance on the job.
- Ignoring moisture on concrete. Tape a 2×2 ft square of plastic to the slab for 48 hours — condensation underneath means you need a moisture barrier before any wood-based flooring goes down.
Flooring FAQs
How do I calculate how much flooring I need?
Total square footage × (1 + waste factor), divided by box coverage, rounded up. Use 10% waste for standard rooms, 15% for tile or diagonal layouts.
How many boxes for a 12×12 room?
144 sq ft + 10% waste ≈ 158 sq ft. At 20 sq ft per box, buy 8 boxes.
Do I need underlayment for vinyl plank?
Only if the product lacks an attached pad. Never double-layer underlayment on floating floors — too much cushion breaks the locking joints.
Can I install flooring over old flooring?
Sometimes: LVP over flat vinyl or tile is common. Never over carpet or cushioned vinyl, and never more than two layers total. When in doubt, remove.
Which direction should planks run?
Along the longest wall or toward the main light source (windows). In hallways, run them down the hall's length.