TL;DR: Flooring in an Idaho custom home fails for climate and structure reasons, almost never for taste reasons. A tight house in a cold, dry valley runs interior humidity in the teens all winter, and that is what opens gaps in a wide plank floor. Tile cracks because the floor framing under it flexes, not because the tile was cheap. Pick the flooring product to match the structure, the heat source and the winter air, lock it before interior doors are ordered, and the floor you pick in the showroom is the floor you still like in year ten.
Contents
- What flooring actually works in an Idaho custom home?
- Why does a dry mountain winter wreck a wood floor?
- Solid wood, engineered, tile, or vinyl plank: how do I choose?
- What does my floor framing have to do with my tile?
- Does Idaho require fire protection under my floor?
- Can I put a wood floor over radiant heat?
- What goes wrong where two floors meet?
- Why does flooring thickness change my stairs?
- How do I know my slab or subfloor is dry enough?
- What does Idaho’s energy code require under my floor?
- When is my flooring decision actually due?
- What does flooring cost in a SwagerBuilds home?
- How I run flooring on a SwagerBuilds build
- Flooring questions I get every week
What flooring actually works in an Idaho custom home?
Almost all of it works, if the house is built and run to suit it. That is the honest answer, and it is less satisfying than a product recommendation.
I have been in construction twenty years and I am involved in every phase of every build, which means I have watched the same four or five flooring arguments play out on job after job. The floor that fails is rarely the wrong species or the wrong tile. It is the right product put over the wrong structure, or over a slab nobody tested, or into a house that spends four months a year at fifteen percent relative humidity.
So the useful version of the question is not “what is the best flooring.” It is three questions:
- What is under it? Slab on grade, a basement floor, engineered I-joists, or open-web floor trusses. That decides what tile and stone you can even consider.
- What is heating it? Radiant in the floor changes the species, the cut, the board width and the assembly.
- What will the air do to it? A tight house in Teton Valley in January is a desert unless you put moisture back in.
Answer those three and the flooring choice narrows to two or three products you will be happy with. Skip them and you are picking out of a showroom catalog and hoping.
Why does a dry mountain winter wreck a wood floor?
Because wood tracks the humidity of the air around it, and our winter air has almost nothing in it.
The National Wood Flooring Association says to hold a house between 60 and 80 degrees Fahrenheit and 30 to 50 percent relative humidity year round. That is the band flooring manufacturers design to. Most flooring leaves the mill dried to between six and nine percent moisture content, which is what wood settles at inside that band.
Now look at what actually happens here. At 25 percent relative humidity, wood settles at roughly five percent moisture content. At 75 percent, it settles at roughly fourteen percent. That is a nine percent swing in the wood itself, and wood that gains or loses moisture changes width.
In a tight, well-insulated house in Driggs or Victor in January, with the furnace running and nothing adding moisture, I see interior humidity sit in the teens. Not 30 percent. The teens. The house is doing exactly what we built it to do, which is not leak air, and the side effect is that every board in the floor shrinks.
That is where the winter gap phone call comes from. The floor is not defective. The floor is responding to conditions nobody told the owner to manage. The flooring manufacturer’s warranty almost certainly names the humidity range it requires, and the house was never run inside it.
There are three real levers, and you pull them during design, not after the floor is down:
- Pick a more stable product. Engineered wood is more dimensionally stable than solid. Narrower boards move less than wide ones. Quarter-sawn and rift-sawn boards hold their width better than plain-sawn. Oak is relatively forgiving; denser species like maple move more for a given moisture change.
- Add moisture back on purpose. A whole-house humidifier on the air handler, sized for the house, is the mechanical answer. This is a decision that belongs with the HVAC design, which is why we settle it alongside whole-house ventilation and the heat source, not after the drywall is up.
- Accept the movement and detail for it. Wider gaps in February are normal in this climate. If that will bother you, do not install a seven-inch plain-sawn solid plank and expect it to behave.
Nobody in this market tells buyers this before they pick flooring. I would rather have the awkward conversation in the design phase than the warranty conversation in year two.
Solid wood, engineered, tile, or vinyl plank: how do I choose?
Here is the honest comparison. I am not going to tell you one product wins everywhere, because it does not.
| Flooring type | How it handles dry winter air | Over radiant heat | What it demands of the structure | Wet areas | Repairable? |
|---|---|---|---|---|---|
| Solid hardwood | Worst. Moves the most. Gaps in winter are the normal outcome, not a defect | Possible but restricted. Narrow boards, quarter-sawn, strict surface temperature limit | Standard subfloor. Flatness matters more than stiffness | No. Not baths, not mudrooms | Yes. Can be sanded and refinished several times |
| Engineered wood | Better. The cross-layered core resists width change | Best wood option. Most products are rated for it | Standard subfloor, flat and dry | Powder room at most | Limited. Depends on wear layer thickness |
| Porcelain or ceramic tile | Indifferent. Humidity does not move it | Best performer. Conducts well, no temperature fight | Highest. Deflection limit of L/360 and a stiff, thick subfloor | Yes, with proper waterproofing | Individual tiles, if you saved extras |
| Natural stone | Indifferent, but brittle | Good | Highest of all. Often L/480 to L/720, sometimes stiffer | Yes, with the right sealer and detailing | Hard. Matching a replacement is luck |
| Luxury vinyl plank | Indifferent to humidity, sensitive to temperature swing | Usually allowed with a temperature cap. Check the specific product | Lowest. Flatness matters, stiffness barely | Yes | Plank by plank on click systems |
Most of the houses I build end up with engineered wood through the main living areas, porcelain tile in the baths and the mudroom, and sometimes stone at a fireplace surround or an entry. That is not a compromise. It is matching each product to the job it is actually doing.
The mistake I see most often is one flooring product carried everywhere for the sake of continuity, and then a bath or a mudroom gets a material that does not belong in a wet room with snow melting off boots. The second most common mistake is the opposite: five flooring products in a 3,000 square foot house, with a transition strip every eight feet.
What does my floor framing have to do with my tile?
Everything. If your tile cracks or your grout lines fail two winters in, the odds are the floor under it is flexing more than the tile can take.
Tile is brittle. It does not bend. The industry limit for ceramic tile over a wood-framed floor is a deflection of L/360, which means the floor may deflect no more than its span divided by 360 under load. Over a fifteen-foot span that is about half an inch of allowable movement. Natural stone is less forgiving: depending on the stone, the requirement tightens to L/480, L/720 or even L/1080.
That is a framing decision, and it is made in the drawing set, long before anybody picks a tile. Practically, it means:
- A minimum 23/32-inch exterior-glue plywood subfloor under any tile floor. That is the floor, not the starting point for negotiation.
- Joists at least 2×10 at 16 inches on center for tile.
- For demanding stone, joists tightened to 12 inches on center or sized up to 2×12, and often two screw-laminated layers of 23/32-inch plywood.
Our houses mostly use engineered floor systems rather than sawn lumber, which changes the math in your favor: engineered I-joists and open-web floor trusses can be specified deeper and stiffer than dimensional lumber over the same span. That is a conversation I have with the engineer during plan development, and it is why the floor system choice between TJIs and floor trusses is not just a cost question.
Here is the part that costs people money. If you decide in month seven that you want a large-format stone in the entry, and the floor was framed to a tile standard, the fix is not a better thinner-set mortar. The fix is structural, and at that point the walls are up over it.
| Finish flooring | Deflection limit | Minimum subfloor | Framing implication |
|---|---|---|---|
| Luxury vinyl plank | Normal code floor is fine | Per manufacturer, flatness driven | None beyond code |
| Engineered or solid wood | Normal code floor is fine | 23/32-inch sheathing, flat | Flatness tolerance, not stiffness |
| Ceramic and porcelain tile | L/360 | 23/32-inch exterior-glue plywood | 2×10 at 16 in. o.c. or engineered equivalent |
| Natural stone | L/480 to L/720, sometimes L/1080 | Often two laminated layers of 23/32-inch | 12 in. o.c. or 2×12, or a deeper engineered joist |
If this sounds like it needs coordinating between the architect, the engineer and the interior selections, it does. That coordination is our job, not yours. Plan development, the drawing set, structural engineering and interior selection sequencing all run through us during the design agreement, which is the point of getting a real number before you sign.
Does Idaho require fire protection under my floor?
No. And that surprises people who have read the national code, because the base code does require it.
The 2018 International Residential Code, at Section R302.13, requires floor assemblies that are not otherwise fire-rated to carry a membrane on the underside of the floor framing: a half-inch gypsum wallboard membrane, a 5/8-inch wood structural panel membrane, or equivalent. It carves out exceptions for floors over sprinklered spaces, floors over a crawl space not used for storage or fuel-fired appliances, up to 80 square feet of unprotected area per story with fireblocking around it, and wood floor assemblies using dimension lumber or structural composite lumber of 2×10 nominal or larger.
Read that last exception again. Sawn 2x10s and bigger were already exempt. The rule was written for the floors that burn through fast, which is engineered I-joists and open-web trusses with their thin webs, exactly the systems most custom homes use now. The APA’s guidance on I-joist fire assemblies exists because of this section.
Idaho deleted it. Section 600 of IDAPA 24.39.30, the state rule that adopts the 2018 IRC with amendments, lists amendment (g) as: “Section R302.13 Fire protection of floors. Delete.” Effective July 1, 2024.
So in an Idaho house, the underside of an engineered floor over an unfinished basement needs no membrane protection at all. Not drywall, not sheathing, nothing. No inspector will ask for it.
I am telling you this for two reasons. First, if you read a national source and come to me asking why your basement ceiling joists are bare, that is why, and it is legal. Second, and this is the part I actually care about: I rock the underside of the floor over an unfinished basement anyway on most builds, because it is cheap at that stage and it buys real minutes in a fire over a floor system that does not have real minutes to give. That is a choice, not a requirement, and you should know which one it is when you are reading a bid. It is one of the line items that explains why two bids on the same house do not compare.
Idaho’s amendment list for the IRC runs from (a) to (q) and touches Section R101.2, R105.2, R301.2.1.2, Table R302.1(1), Table R302.6, R302.13, R303.4, R313.1, R313.2, R314.2.2, R315.2.2, R322.1.10, the footing tables at R403, R403.1.1 and R602.10. That is the whole list. Anything not on it applies as printed in the published 2018 IRC, which matters in the next two sections.
Can I put a wood floor over radiant heat?
Yes, and it is one of the best combinations in this climate. But radiant narrows your flooring choices, and the single number that governs it is the floor surface temperature.
NWFA’s radiant heat guidance caps maximum subfloor surface temperature at 85 degrees Fahrenheit. That applies across the assemblies: glue-down, direct nail, sleeper systems, plywood over the tubing, and floating engineered floors. Above that, you are cooking the floor from underneath and driving its moisture content down below where any product is happy.
That cap has a consequence most people miss. If the floor cannot exceed 85 degrees, the floor can only deliver so much heat per square foot. Pile a thick, insulating floor covering on top of radiant tubing and you lose output, and the usual response is to raise the water temperature, which pushes the surface past the cap. That is how a radiant floor ends up both underperforming and wrecking the flooring over it.
What actually works over radiant, in order:
- Porcelain or ceramic tile. Conducts heat well, does not care about the dryness, no temperature fight. If the room is radiant and wet, tile is the answer.
- Engineered wood rated for radiant. The cross-layered core handles the moisture gradient that radiant creates through the thickness of the board.
- Narrow, quarter-sawn or rift-sawn solid wood. Workable, with discipline. NWFA specifically does not recommend solid wood four inches and wider over sleepers.
- Luxury vinyl plank with a verified temperature rating. Many products allow it; some do not. Read the specific product’s limit rather than the category’s reputation.
What does not work: thick carpet with a thick pad, wide plain-sawn solid plank, and anything whose manufacturer is silent on radiant. Silence is not permission.
If radiant is on the table, read what radiant floor heat costs in Idaho alongside this, because the flooring decision and the heat decision have to be made together. Picking flooring first and radiant second is how you end up with a floor that heats a room four degrees.
What goes wrong where two floors meet?
Transitions. This is the unglamorous half of a flooring package and it is where good houses look cheap.
The problem is thickness. Every flooring product has its own build-up height: tile plus mortar plus an uncoupling membrane is a different stack than engineered wood plus underlayment, which is a different stack than vinyl plank straight on the subfloor. Put them next to each other without planning and you get a lip, and a lip gets a strip of metal or wood screwed over it to hide it.
The fix is to plan the thickness, not to cover it. That means:
- Decide every flooring material in the house before the subfloor is finished. Then the finish floor heights can be made to land flush where they meet, with the subfloor shimmed, recessed or built up as needed.
- Put the transitions under doors wherever possible. A material change that happens under a closed door reads as intentional. A material change in the middle of an open sight line reads as a mistake.
- Settle curbless showers at framing. A shower floor flush with the bathroom floor means dropping the floor framing in that bay. That is a framing-crew decision, not a tile-sample decision, and it cannot be retrofitted cheaply.
- Know that finish floor height sets door undercut. Interior doors get ordered and cut to the finish floor. Change the flooring after the doors are ordered and you are either re-cutting doors or living with a gap, which is covered in more detail in how interior doors and trim get picked.
There is one more thing about door undercut that cuts against the flooring instinct. The gap under a closed door is the return air path for most rooms in a house without a dedicated return in each room. Seal it up with a thick flooring stack and a tight threshold and you pressurize the room. Open it up and the sound travels. There is no free answer, which is why it gets decided with the mechanical design.
Transitions are also a place where the drawing set earns its money. We detail them during plan development, in-house, which is faster than waiting on an outside firm’s calendar for a revision.
Why does flooring thickness change my stairs?
Because the code tolerance on stair risers is three-eighths of an inch, and a flooring change at the top or bottom of a flight eats most of that by itself.
Idaho’s amendment list for the IRC does not touch Section R311. I checked the whole list, (a) through (q), and stairways are not on it. That means the 2018 IRC stairway rules apply here exactly as printed: maximum riser height 7 3/4 inches, minimum tread depth 10 inches, and the greatest riser height within any flight may not exceed the smallest by more than 3/8 inch. Same 3/8-inch tolerance on tread depth.
Now picture a real build. The stair gets framed to equal risers off the subfloor. Then hardwood goes in at the top landing and tile goes in at the bottom, and the tile stack is a quarter inch thicker than the wood. The bottom riser just got a quarter inch shorter and the top riser got whatever the hardwood added. You have spent most of your 3/8-inch tolerance on a selection nobody cross-checked, and if the flooring at one end changes again, you fail.
This is the single most common flooring mistake I correct on other people’s drawing sets. The framer needs the finish floor thickness at both ends of every flight before the stringers are cut. That is a flooring decision delivered to the framing crew, weeks before anybody is thinking about flooring.
It is also one of the items on the list when we walk a house before the drywall goes on. If a riser is out, the time to find it is at the pre-drywall walkthrough, not at the framing inspection and definitely not at the final walkthrough.
How do I know my slab or subfloor is dry enough?
You test it, with a method the flooring manufacturer names, and you keep the result on paper.
This is the failure that costs the most to fix, because by the time it shows up the flooring is installed and furnished. Moisture coming up out of a slab or a damp subfloor will cup wood, debond glue-down products, and trap under vinyl.
For a concrete slab, the method that matters is ASTM F2170, the in-situ relative humidity test. Probes go into holes drilled to 40 percent of the slab depth, they equilibrate, and they read the humidity inside the slab rather than at its surface. Surface tests read the room as much as the concrete. Most flooring manufacturers state a maximum internal relative humidity they will warrant over, and that number is the gate.
A new slab needs time. How much depends on thickness, mix, weather and whether the building is dried in, which is exactly why the dried-in-before-winter question drives so much of our scheduling. Pouring late and then rushing flooring is a predictable way to buy a floor twice.
| Substrate | Test | What it reads | Who owns it |
|---|---|---|---|
| Concrete slab on grade or basement slab | ASTM F2170 in-situ RH probes | Humidity inside the slab at 40 percent of its depth | Flooring installer, before any material lands |
| Wood subfloor | Pin or pinless moisture meter | Moisture content of the sheathing | Flooring installer, compared against the flooring itself |
| The flooring material | Moisture meter on the product | Moisture content, normally 6 to 9 percent from the mill | Flooring installer, documented on site |
| The room | Thermohygrometer | Temperature and relative humidity at install | Us, with the HVAC running and set |
The gap between the subfloor moisture content and the flooring moisture content is the one people forget. If the flooring sits at six percent and the subfloor sits at twelve, the flooring will take on moisture after install and cup. Both numbers have to be read, not just one.
Below a slab, the other moisture decision is the vapor barrier and the sub-slab detailing, which is settled when you choose between a basement, a crawl space or a slab. Building Science Corporation’s work on basements is the clearest explanation I have found of why a slab without a proper capillary break will keep feeding moisture into whatever you put on it. The same sub-slab work interacts with radon mitigation, so it gets detailed once, correctly.
What does Idaho’s energy code require under my floor?
Idaho adopts the 2018 IECC with state amendments, and it rewrote the insulation table. The numbers that touch your floor are specific, and they change by climate zone.
Amendment (b) in Section 600 of IDAPA 24.39.30 deletes the climate zone 5 and 6 rows of Table R402.1.2 and replaces them. For a floor, here is what Idaho actually requires:
| Component | Climate zone 5 | Climate zone 6 |
|---|---|---|
| Floor R-value | R-30 | R-30 |
| Slab R-value and depth | R-10, 2 ft | R-10, 4 ft |
| Basement wall R-value | R-15/19 | R-15/19 |
| Crawl space wall R-value | R-15/19 | R-15/19 |
| Ceiling R-value | R-38 | R-49 |
The one that bites is the slab row. Zone 5 wants R-10 insulation to two feet of depth. Zone 6 wants the same R-10 taken to four feet. That is double the vertical run of rigid foam at the slab edge, and it is a detail that has to be in the drawing set and in the bid, because nobody adds it after the concrete is poured. The Department of Energy’s slab edge insulation guide covers why the slab perimeter is where the heat leaves.
A cold slab is also a flooring problem, not just an energy problem. Cold concrete under a flooring product is where condensation happens, and a floor that is ten degrees colder than the room is a floor nobody wants to stand on, whatever you put over it. This is one more reason the flooring conversation belongs in the same room as the insulation strategy and the window package.
Two more floor-adjacent items worth knowing. Idaho’s amended table also sets the frame wall at R-22 or R-13 plus R-5 continuous in zone 6, versus R-20 or 13 plus 5 in zone 5. And snow load drives the structure above, which drives joist depth, which comes back around to the deflection numbers in the tile section.
When is my flooring decision actually due?
Earlier than you think, and the reason is not the flooring lead time. It is everything the flooring thickness locks downstream.
| Flooring decision | Due by | Why that deadline | What it locks |
|---|---|---|---|
| Tile and stone locations | Design phase, before structural drawings are final | Deflection limits set joist depth and spacing | Floor framing, subfloor thickness, engineering |
| Radiant heat zones | Design phase, with the mechanical design | The 85-degree surface cap limits output per square foot | Flooring product, species, board width, heat source sizing |
| Curbless shower locations | Before floor framing is sheathed | The floor has to be dropped in that bay | Joist layout, waterproofing, drain type |
| Finish floor thickness at every stair | Before stair stringers are cut | The 3/8-inch riser tolerance | Stair framing, and whether the stair passes inspection |
| Every flooring material and its build-up | Before interior doors are ordered | Finish floor height sets door undercut | Door heights, thresholds, transitions, return air path |
| Grout, sealer, stain and sheen | Finish stage | Nothing downstream depends on it | Nothing. This is the one you can genuinely sit on |
That table is the single most useful thing on this page. The flooring choices people agonize over, which is color and grain and grout, are the ones with no downstream consequence. The flooring choices people wave off, which is where the tile goes and how thick each stack is, are the ones that change framing.
This sits inside the larger selections sequence. If you want the full picture of when every finish decision is due, that is laid out in when finish selections are due, and the whole build sequence is in the start-to-finish checklist.
Interior design coordination is part of what we do, not something you go source separately. Finish selection, cabinetry and millwork out of our Rigby shop, lighting, tile and the sequencing of all of it is coordinated in-house so the selections do not blow up the schedule.
What does flooring cost in a SwagerBuilds home?
I am not going to publish a per-square-foot flooring number, and I want to explain why rather than dodge.
Flooring price per square foot is the least meaningful number in a flooring bid. The same engineered oak can be installed over a flat, dry, tested subfloor in four days, or over a slab that needs grinding, a self-leveler and a moisture mitigation coating, which triples the labor and adds materials nobody quoted. A tile floor that needs the framing stiffened is not a tile price at all. It is a framing price. Any flooring number I published would be wrong for your house in a way that would cost you real money to discover.
What I will tell you is how SwagerBuilds prices. A custom home here starts at $400 per square foot of conditioned space and goes up. In Jackson Hole it starts at $1,000 per square foot and goes up. Design work is a fixed design fee, quoted per project. The flooring package lives inside that construction number as a scoped line item with a real product specified, not an allowance with a guess attached.
That last distinction matters more than any price. A vague flooring allowance is one of the most reliable ways a build goes over budget, because the allowance gets set low to make a bid look competitive and the overage shows up in month nine when you have no leverage. What it honestly costs to build in Teton Valley and what a custom home costs in Idaho both go into how that number gets built.
What is not in a flooring number, since you were about to ask: the subfloor prep, the moisture testing and any mitigation it triggers, the structural work tile or stone may demand, transition details, stair treads and risers, and the humidification equipment that keeps a wood floor inside its warranty. Those are separate scopes that a flooring price per square foot never includes, and the last one is HVAC.
If you are weighing where the money is best spent, which upgrades are actually worth it covers how I rank flooring against the other places a budget can go.
How I run flooring on a SwagerBuilds build
Four things, every time.
Flooring materials are locked before the structural set is final. Not the color. The material and its build-up height, room by room, on a plan. The engineer gets it, the framer gets it, the stair builder gets it. This one habit removes most of the failures on this page.
Nothing goes down until four numbers are on paper. Slab internal relative humidity by ASTM F2170 where there is a slab, subfloor moisture content, flooring moisture content, and the room’s temperature and humidity with the HVAC running and set. If those four do not line up with what the manufacturer requires, we wait. Waiting is cheaper than a floor.
The house gets conditioned before the floor arrives, and stays that way. The heat is on, the humidification is running, and the house is sitting inside the band the flooring is warranted for. A floor installed into a job-site climate and then moved into a lived-in climate is a floor that moves twice.
I am on the job through all of it. I do not lay the tile and I do not run the flooring nailer. My tile sub and my flooring crew do that, and they are good. What I do is sequence it, check it against the drawing set, and catch the quarter inch at the bottom of the stair before it becomes a code problem. Twenty years in and that is still where the value is. There are 24/7 cameras on every job, so you can watch your own floor go in from wherever you are.
If you are planning a build in Teton Valley, Jackson Hole or Eastern Idaho and you want the flooring decided properly instead of late, call me at (208) 520-0636 or start a conversation here. Bring your lot and a rough idea of the house. We will talk about what is under the floor before we talk about what goes on top of it.
Built different. Built right. Built by SwagerBuilds.
Flooring questions I get every week
Will my hardwood floor gap in an Idaho winter?
Probably, to some degree, and that is normal here rather than a defect. Wood settles at about five percent moisture content at 25 percent relative humidity and about fourteen percent at 75 percent, and a tight Idaho house in January often sits in the teens. The fixes are choosing a more stable product, narrower boards and quarter-sawn or rift-sawn material, and running a whole-house humidifier to hold the house inside the 30 to 50 percent band flooring manufacturers warrant.
What is the best flooring to put over radiant floor heat?
Porcelain or ceramic tile first, then engineered wood rated for radiant. The governing number is a maximum subfloor surface temperature of 85 degrees Fahrenheit, so any floor covering that insulates heavily fights the system. Narrow quarter-sawn solid wood can work, but solid wood four inches and wider is not recommended over sleepers. Check the specific product’s radiant rating rather than trusting the category.
Why did my tile floor crack?
Most often because the floor under it flexes more than the tile can tolerate. Ceramic tile over a wood-framed floor requires deflection no greater than L/360, and natural stone often requires L/480 to L/720 or stiffer. That calls for a minimum 23/32-inch exterior-glue plywood subfloor and framing sized for the span. It is a structural decision made in the drawing set, not something a better mortar fixes later.
Does Idaho require drywall under the floor joists in an unfinished basement?
No. The 2018 IRC Section R302.13 requires a half-inch gypsum or 5/8-inch wood structural panel membrane on the underside of floor framing, but Idaho deleted that section entirely in IDAPA 24.39.30, effective July 1, 2024. No inspector will require it. I still do it on most builds over engineered floor systems, because it buys real time in a fire, but it is a choice and you should know whether a bid includes it.
When do I have to pick my flooring?
Tile and stone locations belong in the design phase, because deflection limits drive joist depth. Radiant zones go with the mechanical design. Curbless showers are settled before the floor framing is sheathed, finish floor thickness at every stair before the stringers are cut, and every material and its build-up height before interior doors are ordered. Grout color, stain and sheen can genuinely wait until the finish stage.