True Inch Standard for Homes · Edition 1.0 · for trial use
How a True Inch Score is made
A True Inch Score rates how well a home's design works for daily living, from 0 to 100, from its floor plan. The home is built from its drawing at its true size, at its real place and facing, and measured: its rooms and the furniture they take, its daylight, the sun through its windows, the air through its rooms, its daily routes and its doors. Each measurement is held to a published level and becomes points by the arithmetic on this page. Nobody sets a score by judgement: the same drawing, the same answers about it and the same edition always give the same score.
Six parts32 checks in India and 33 in the USEdition 1.0, for trial use until October 2028
Its principles
Measured, not guessed. Every number comes from a computation on the model of the home, with its method, its inputs and its status.
The score is computed. The plan, the inputs used and the edition determine the score. Nobody, human or model, sets a number by judgement.
Honest about what is unknown. What can't be measured is left unscored and becomes a question. What rests on an assumption says so. Where an unknown could move the score, the score is shown as a range.
Anchored and labelled. Every threshold names its source and its kind: a code, a standard, a recommendation, a convention, or a measure of our own.
Taste and belief are not scored.
Open and versioned. Every check, curve and weight is published, and every report names the edition that scored it.
Every finding leads to an action: ask, check, change, negotiate, or accept, with the reason.
What it isn't
a review against a building code;
an inspection of construction or condition;
a valuation;
a certified measurement;
an energy rating;
a judgement of taste, or of beliefs such as Vastu.
What it is for
comparing homes;
deciding before buying, renting or building;
finding what is worth fixing, and what to ask.
What it rates
Six parts, each scored from 0 to 100, make the score, and each counts by its weight. The weights are the standard's (Part 1 §7.3); during trial use, panels of practising architects in each market test them (Annex C).
- Space20
- Room sizes and the fit of real furniture
- Daylight15
- How bright the rooms are by day
- Sun15
- Welcome and unwelcome sun
- Air20
- Fresh air, cross-ventilation, cooking smells and breeze
- Layout20
- Daily routes, privacy, doors and the kitchen
- Safety & access10
- Widths, steps, stairs, falls and escape
What it leaves out
construction quality, materials, finishes and condition;
structure and building services;
legal status, approvals and title;
location, neighbourhood, common areas and amenities;
price and value;
energy use;
outside noise and air quality;
the view out;
shading by surrounding buildings and trees, unless declared (edition 1.0 assumes an open sky; 8.4).
Nor whether a home's printed sizes are true: that is the size check, which a report shows beside the score and never mixes into it (Part 2-IN §9, Part 2-US §9).
What a score means
The total falls in one of five bands.
- Poor0–39
- Fair40–54
- Good55–69
- Very good70–84
- Excellent85–100
Within it, every check and every part is held to the same three levels:
- 50 Minimum
- What a code asks, or the least a standard or the evidence accepts. A 50 means adequate, not typical.
- 75 Medium
- Good practice: a standard's own middle level, or what a professional body recommends.
- 100 High
- The best the standard rewards. A room brighter or airier than high scores no more.
One number, or a range. Where what the drawing doesn't say (the windows' sills, their type, the ground round the home) leaves the score's likely range 3 points wide or more, the report shows that range: two times in three, the score falls within it. Where nothing says which way the home faces, there is no single score: it is given facing each way, and the report asks first.
Its edition. Every score names the edition it was made under: True Inch Score 74 (TIS-IN 1.0) is India's Part with Part 1, edition 1.0. A report keeps its edition; a newer edition makes a new report, and the old one stands (Procedures §6).
Where each level comes from
Every level a check is held to names its source, and the kind of source it is. A report says which: a code asks, a standard sets, a professional body recommends.
| Kind | What it is | India | United States |
|---|---|---|---|
| Code | A rule homes must meet where it applies, read in its own text: the International Residential Code, say. | 2 | 11 |
| Model code | A national model code, binding where a state or a city adopts it: India's National Building Code. | 10 | – |
| Standard | A published technical standard: EN 17037 for daylight, ASHRAE 55 for comfort. | 12 | 9 |
| Recommendation | A professional body's guidance: NKBA's for kitchens, the UK's Approved Document M4(2). | 4 | 8 |
| Convention | How things are commonly sized: mattresses, a kitchen platform, a wardrobe. | 5 | 3 |
| Our measure | Where nothing sets a level, the standard sets its own and says why; where it can, it fixes it on its reference set of plans, so that a 50 is as hard to earn there as on the checks a standard anchors. | 8 | 8 |
The last two columns: how many of each market's checks lean on a source of that kind.
The words a report keeps to
A report shall not say "complies", "safe", "healthy", "quiet", "guaranteed", "certified" or "Vastu-compliant".
"Meets" may be used only of a gate that passed, naming it: "meets NBC Part 3's minimum".
Kinds. A report shall name each threshold's kind.
The drawing. It shall say "the drawing shows" of the built home.
How it is worked out
From what the home measures to its score, in ten steps. Each says what it does, then exactly what it does, with the clause of Part 1 that sets it.
1Measure the home
The home is built from its drawing at its true size, every printed dimension checked against it, and measured under the conditions Part 1 and its market's Part set: daylight under an overcast sky, the sun minute by minute through every window, the air through every window and door, the routes walked, the furniture at real sizes with its clearances. The same model, answers and edition always measure the same. The engines are held to references of their own:
Engine Validated against Daylight A Radiance referee Sun position NREL's SPA, to within 0.01° Airflow Published multizone methods The reading Printed dimensions, through the reading scorecard Part 1 §5
2Turn each measurement into points
A graded check turns what it measures into points by a curve fixed to its levels: none at its zero, 50 at the minimum, 75 at medium and 100 at high, and nothing more past it, however bright or airy a room is. Between them the points rise in a straight line on the measure's own scale: a logarithmic one for lux, air changes, hours and lengths, where each doubling counts alike, and a linear one for shares and counts. Where less is better (heat through the glass, a smell's reach), the curve runs the other way.
DL-2 How bright by day, in a living or dining room, as Part 2-IN scores it (Part 2-US holds it to the same levels): the light reached over half the room for half the daylight hours. p(x) = 0, where x ≤ x0
p(x) = 50 · [g(x) − g(x0)] / [g(xmin) − g(x0)], up to the minimum
p(x) = 50 + 25 · [g(x) − g(xmin)] / [g(xmed) − g(xmin)], up to medium
p(x) = 75 + 25 · [g(x) − g(xmed)] / [g(xhigh) − g(xmed)], up to high
p(x) = 100, where x ≥ xhigh
g(x) = ln x on a logarithmic scale, x on a linear one. Where less is better the anchors run the other way, xhigh < xmed < xmin < x0.
A check whose levels are tests a drawing passes or not (a bed with its walkways, a kitchen's aisle) gives 100, 75 or 50 for the highest level whose tests all pass. A room that misses the minimum only by a clearance of 150 mm or less gets 25, and otherwise none.
Part 1 §6.3
3Hold the codes' minimums as gates
Where a code sets a minimum (a room's area, a window's size), the check is a gate. Passing it costs nothing. Failing it costs its part points by how far short the home falls, and a part loses at most 50 to its gates. Every failure is a finding. Where the code allows what a drawing can't show (electric light for a window, a fan for an opening), the report asks for it to be confirmed, and never calls the home unlawful.
P = min(25, 10 + 50 · s)
s is the shortfall as a share of what the code asks; 0.5 where the rule has no quantity.
The points a failed gate costs its part, by how far short the home falls. Part 1 §6.5
4Count each room by the hours spent in it
A check measured room by room is the mean of its rooms' points, each weighted by the hours a day a person spends in it, times the people who use it: a bedroom its own occupants, a shared room the whole household. Daylight and Sun count the hours of daylight or waking, Air and Space all of them, so a bedroom counts its nights. Where the worst habitable room scores under 50, it is named beside the score.
India: hours a day in each room Room All Daylight Bedroom 9.5 1 Living 4 3 Dining 1.5 0.7 Kitchen¹ 2.5 2 Study, office¹ 1.5 1.5 Bath, WC 1 – Utility, laundry¹ 0.5 0.5 Balcony, outdoor¹ 0.5 0.5 Pooja room¹ 0.3 – Each person's hours; ¹ the household's together. A dash: not counted for daylight. The household it is assessed for: 2 people in a studio, 2 with 1 bedroom, 4 with 2 bedrooms, 5 with 3, 6 with 4; with more bedrooms, 2 more than its bedrooms.
United States: hours a day in each room Room All Waking Bedroom 9 1 Living 3.5 3.5 Dining 0.5 0.5 Kitchen 1.1 1.1 Study, office 1 1 Bath, WC 0.5 – Utility, laundry 0.1 0.1 Garage 0.05 – Balcony, outdoor 0.25 0.25 Home gym 0.3 0.3 Each person's hours. A dash: not counted for daylight. The household it is assessed for: 1 person in a studio, 2 with 1 bedroom, 3 with 2 bedrooms, 4 with 3, 5 with 4, 6 with 5; with more bedrooms, one more than its bedrooms.
Part 1 §7.1
5Make each part from its checks
A part is the weighted mean of its checks that were scored, less its gates' penalties, kept within 0 and 100. Each check's weight within its part is with the check, below.
Ppart = clip( Σ wc · pc / Σ wc − Σ penalties, 0, 100 )
Sun weighs the sun a home welcomes in its cool season (SN-1) against the sun it would rather keep out in its hot one (SN-2), by its climate: SN-1 counts for w of the part and SN-2 for 1 − w, where w is the cool sunny hours ÷ (cool sunny hours + hot sunny hours), from the place's typical year. Cool is 20 °C or below, hot 27 °C or above, and sunny is direct sun of 120 W/m² or more. Without the year, India takes its climate zone's: warm-humid 0.05, hot-dry 0.25, composite 0.3, temperate 0.15, cold 0.7; the US, 0.6.
Air, in the US, counts its natural ventilation (AR-1, AR-2, AR-3, AR-6) by how much its climate makes it worth: each weight times m = 0.4 + 0.6 f, f the share of waking hours pleasant with the windows open, from the typical year. India's air counts in full.
Part 1 §7.2
6Make the total from the parts
The six parts make the total by a weighted geometric mean, so a weak part pulls it down more than a strong part pushes it up: a dark home can't buy its score back with space. Each part counts by its weight times its coverage, the share of its checks' weight that could be scored, so one scored check can't speak for a whole part.
T0 = exp( Σ Wk · ck · ln(max(Pk, 1)) / Σ Wk · ck )
Wk is part k's weight (Space 20, Daylight 15, Sun 15, Air 20, Layout 20, Safety & access 10); ck its coverage.
Four homes (Part 1 Annex B): their parts, averaged, and as the geometric mean makes them Home Space Daylight Sun Air Layout Safety & access Averaged The score A, roomy but dark and stuffy 90 25 50 35 85 85 61.8 Good 55.3 Good B, compact, bright and airy 55 80 70 80 65 75 70 Very good 69.3 Good C, balanced 68 68 68 68 68 68 68 Good 68 Good D, excellent except its daylight 95 10 60 90 90 90 74.5 Very good 61.6 Good Under an arithmetic mean, home D's space buys back its dark rooms, and it would be Very good.
Under the geometric mean it is Good, below the balanced home C.
For home A, 10 more points of Daylight add 2.9 to the total; 10 more of Space add only 1.2. The improvements that lead the report are, rightly, the ones that fix the weakest part.
Part 1 §7.3
7Cap it where something critical is wrong
A critical issue holds the total down whatever else the home does well: one caps it at 69 (Good at best), two or more at 54 (Fair), and the report shows the score before the cap. And a home with any part under 50 can't be Excellent: its total is held at 84 (Part 1 §7.5). Each market's critical issues:
India
- A bedroom or living room with no window or glass door to the outside
- A bedroom reached only through another bedroom
- A kitchen with no opening to outside air, which is unsafe for gas and smoke
United States
- A bedroom or living room with no window or glass door to the outside
- A bedroom reached only through another bedroom (IPMC 404.4.2)
- A sleeping room whose windows can't meet the escape size (IRC R310)
- An opening from the garage into a sleeping room (IRC R302.5.1)
Part 1 §7.4
8Give a total only on enough
Coverage is the share of the method's weight that could be scored. Under 80% no total is given: the report shows the parts it could score, names the checks it couldn't, and asks the questions that would score them. Otherwise the total says what share it was scored on.
C = Σ Wk · ck / Σ Wk
Part 1 §7.6
9Say which way it faces, and what isn't known
Facing. The sun and the breeze turn with the home. With nothing to tell which way it faces, there is no single score: the report gives the score with the top of the drawing to the north, east, south and west, and asks first which way the home faces. A facing that is told carries its own doubt into the likely range: ±2σ of the reading where the plan's north arrow gives it, ±22.5° where the owner gives one of eight directions.
What isn't known. The score is worked out again 32 times over what the drawing doesn't say, by Latin-hypercube draws that are the same for every home (seed 1): the windows' sills and heads, ±150 mm where they aren't printed, a home's windows together; their type where none is drawn; and the ground round the home where nobody has said. The 3D breeze is too slow to draw again, so its speeds are scaled by its bench error, a factor of 2 either way at one standard deviation.
India's draws
- Windows: sliding 50%, casement 50%
- The ground: a flat, city 50%, suburban 50%; a house, suburban 50%, city 25%, open 25%
The US's draws
- Windows: hung 50%, sliding 25%, casement 25%
- The ground: a flat, city 50%, suburban 50%; a house, suburban 50%, open 25%, city 25%
The likely range is the draws' 17th to 83th percentile: two times in three, the score falls within it. The very likely range, 5th to 95th, is nine times in ten. A report shows the likely range where it is 3 points wide or more, both bands named where it crosses a band's edge. The score itself stays the home at its stated assumptions, which the report lists: its factors add up to it, and every figure shows that home.
Edition 1.0 assumes an open sky (Part 1 §8.4): the sun and the daylight a report shows are the most the home can get, with no shade from the buildings and trees round it.
Part 1 §8
10Round it, and show every point lost
The total and the parts are whole numbers, halves rounded up. Every point the home loses is a line beside its score, its factor: shared among the parts as below (exactly, under the geometric mean, and nothing for a part at 100); within a part among its checks by wc(100 − pc), its gates' penalties counted as their own; within a check among its rooms by their weight times what each falls short. The caps and the balance rule are factors of their own, and the factors are rounded so that they add up to the points lost as shown.
losti = (100 − T0) · Wi · ci · ln(100 / Pi) / Σ Wj · cj · ln(100 / Pj)
Part 1 §7.7
The checks
Each market's Part 2 sets its checks: what each measures, the levels it is held to, and where each level comes from. Here they are as the score runs them, each curve drawn from the method itself; the words of each are in its Part.
TIS-IN 1.0 · India's checks, as Part 2-IN: India sets them
Space20 of the score's 100
- Model codeNBC 2016 Part 3 §12 (room sizes), or the city's rules
- ConventionIndian mattress sizes, 75″ long
- RecommendationUK Approved Document M4(2) §2.25: 750 mm around the main bed
- Convention600 mm walkway, engine practice
- RecommendationSeats for the design household; NKBA's 32/36/44″ seating clearances
- ConventionPlatform run of 2.4 / 3.0 / 3.6 m, 600 mm deep at 850–900 mm
- ConventionWardrobe runs of 1.2 / 1.8 / 2.4 m (main bedroom); the UK space standard's storage
- Our measureA sit-out 1.2 / 1.5 / 1.8 m deep; the London Plan's size
- Our measureShare of floor only for passing; anchors provisional: the reference set can't fix them
Provisional: the reference set can't fix it yet SP-8Ceiling heightGraded · 5 of Space's 100
Its gate, a code's minimum:
SP-8gCeiling height: the code's least- Model codeNBC 2016 Part 3 §12: 2.75 m in habitable rooms
- StandardNBC Part 8: a fan hangs at its best height and clears 2.4 m at 2.95 m
- Our measureA double-door fridge, a three-seat sofa and a washing machine carried in
- ConventionA washing machine's place; a utility balcony off the kitchen
Daylight15 of the score's 100
- Model codeNBC 2016 Part 3 §20.1.2: openings by climate zone, kitchens 25% more
- StandardUK National Annex to EN 17037 (dwellings): the minimum
- StandardEN 17037: 300 lux (medium) and 500 lux (high) over half the room
Bedroom Living, dining Kitchen Study, home office DL-3Depth and evennessGraded · 30 of Daylight's 100
Its gate, a code's minimum:
DL-3gDepth from a window- StandardEN 17037: 100 lux and 300 lux over 95% of the room
Sun15 of the score's 100
- StandardEN 17037 sunlight exposure: 1.5 / 3 / 4 hours
- Model codeNBC Part 8 §3.4: winter sun in, summer sun out
- Our measureSun through the glass per m² of floor on hot days; fixed on the reference set, its shape from Eco-Niwas Samhita's orientation factors
Fixed on the reference set, 7 October 2026
Air20 of the score's 100
- RecommendationIGBC Green Homes v3: living 10%, kitchen 8% openable (minimum)
- CodeEco-Niwas Samhita: openable ratio for the climate zone (medium)
- Model codeNBC Part 8 §5.4.3.1: 20–30% of the floor (high)
Warm-humid Composite Temperate Hot-dry Cold - StandardUK Approved Document F: purge at 4 air changes an hour
- Model codeNBC Part 8 §5.2.2.1: bedroom 2–4, living 3–6 an hour
Usual wind, windows open by their share Still air: bedrooms at night, doors shut Still air: living - CodeEco-Niwas Samhita 2024: 50 / 75 / 90% of lived-in floor cross-ventilated
AR-4Wet roomsGraded · 10 of Air's 100
Its gate, a code's minimum:
AR-4gWet rooms: openings- Model codeNBC 2016 Part 3 §12.4.3: a window of 0.3 m² to open air or a shaft
- StandardIS 3362; NBC Part 8: 6–10 air changes an hour in wet rooms
- Our measureKitchen smells reaching bedrooms and living, and clearing; fixed on the reference set
Kitchen → bedrooms and living: peak share · fixed on the reference set, 7 October 2026 Time for the living space to clear, after the cooking stops · fixed on the reference set, 7 October 2026 WC → kitchen and dining: peak share · fixed on the reference set, 7 October 2026 - StandardNBC Part 8 Table 9's desirable air speeds; ASHRAE 55's elevated air speed
- Model codeNBC 2016 Part 3 §12.4.4: a WC room must not open directly into a kitchen
Layout20 of the score's 100
- Our measureWhat a visitor sees from the main door; Indian conventions of the foyer
LY-2Daily routesGraded · 30 of Layout's 100 · levels met or not
Its gate, a code's minimum:
LY-2gA toilet without crossing another bedroom- Our measureThe engine's walking widths: easy at 900 mm, tight at 600 mm
- ConventionThe Indian common toilet; a bedroom only through another is critical
- Our measureDoor leaves that hit each other, a fixture or furniture
- RecommendationNKBA's work triangle; UK M4(2)'s 1,200 mm aisle
- StandardNBC 2016 Part 8 Sec 4 §5.2: rooms laid out by the noise they make and mind
Safety & access10 of the score's 100
SF-1Widths and doorsGraded · 35 of Safety & access's 100 · levels met or not
Its gate, a code's minimum:
SF-1gWay-out door and halls- StandardCity rules' door sizes; NBC Annex B and the Harmonised Guidelines 2021
- StandardNBC Annex B and the Harmonised Guidelines 2021: thresholds of 12 mm at most
SF-3StairsGraded · 20 of Safety & access's 100 · levels met or not
Its gate, a code's minimum:
SF-3gStairs: the code's sizes- Model codeNBC 2016 Part 3 §12.18; MBBL §4.17: 1.0 m wide, 250 mm treads, 190 mm risers, 12 a flight
- StandardNBC Annex B: 300 mm treads, 150 mm risers, handrails
- StandardNBC 2016 Part 6 Sec 8 Table 35: a sill or its guard 800 / 1,100 / 1,200 mm up, by the floor
- StandardIS 4912: a guard where a sill under 900 mm has a drop over 1.2 m
TIS-US 1.0 · the US's checks, as Part 2-US: United States sets them
Space20 of the score's 100
- CodeIRC 2021 R304: 70 ft² and 7 ft in any direction
- ConventionMattress sizes (ISPA)
- RecommendationUK Approved Document M4(2) §2.25: 30″ around the main bed
- RecommendationSeats for the household; NKBA's 32/36/44″ seating clearances
- RecommendationNKBA counter frontage and landing areas
- ConventionCloset rod of 4 / 6 ft per person; a primary walk-in
- Our measureA house's patio, deck or porch of 54 / 100 / 200 ft²; an apartment's balcony 4 ft deep, then 5 m² and 1 m² a person past two; the London Plan's size
- Our measureShare of floor only for passing; anchors provisional: the reference set can't fix them
Provisional: the reference set can't fix it yet SP-8Ceiling heightGraded · 5 of Space's 100
Its gate, a code's minimum:
SP-8gCeiling height: the code's least- CodeIRC R305: 7′0″
- Convention8′0″ and 9′0″ ceilings
- Our measureA 36″ fridge, an 84″ sofa and 27″ machines carried in
- RecommendationA laundry room near the bedrooms (NAHB's most-wanted feature)
Daylight15 of the score's 100
- CodeIRC R303.1: glazing at least 8% of the floor (or 6 fc of electric light)
- StandardUK National Annex to EN 17037 (dwellings): the minimum
- StandardEN 17037 and LEED v5: 300 and 500 lux over half the room
Bedroom Living, dining Kitchen Office, den - StandardEN 17037: 100 lux and 300 lux over 95% of the room
Sun15 of the score's 100
- StandardEN 17037 sunlight exposure: 1.5 / 3 / 4 hours
- StandardNGBS 703.7.1 glazing budgets: west 2%, east 4%; IRC's 8% glazing all west
Air20 of the score's 100
- CodeIRC R303.1 and ASHRAE 62.2 §6.5: openable 4%
- CodeNYC: 5%
- StandardUK Approved Document F: purge at 4 an hour; NIST's ventilative cooling at 15
Usual wind, windows open by their share - StandardNGBS 902.1.5: operable openings on two walls
AR-4Wet roomsGraded · 15 of Air's 100 · levels met or not
Its gate, a code's minimum:
AR-4gWet rooms: openings- CodeIRC R303.3, M1505; ASHRAE 62.2-2025 toilet-room fans
- Our measureKitchen smells reaching the bedrooms with the hood on; fixed on the reference set
Kitchen → bedrooms: peak share · fixed on the reference set, October 7, 2026 - StandardASHRAE 55: elevated air speed in the adaptive model
AR-7The garageGraded · 5 of Air's 100 · levels met or not
Its gate, a code's minimum:
AR-7gA way out not through the garage- CodeIRC R302.5–R302.6 and R311.1: the garage's openings, and a way out not through it
- Our measureA buffer room between the garage and the house, and no room over it
Layout20 of the score's 100
- Our measureWhat a visitor sees from the front door
LY-2Daily routesGraded · 30 of Layout's 100 · levels met or not
Its gate, a code's minimum:
LY-2gA toilet without crossing another bedroom- CodeIPMC 404.4.3: a toilet without passing through another bedroom
- RecommendationVisitability; NGBS 612.3
- Our measureDoor leaves that hit each other, a fixture or furniture
- RecommendationNKBA kitchen planning guidelines
- Our measureBedrooms beside the kitchen, the living space, a toilet, the garage or a laundry
Safety & access10 of the score's 100
SF-1Widths and doorsGraded · 40 of Safety & access's 100 · levels met or not
Its gate, a code's minimum:
SF-1gWay-out door and halls- CodeIRC R311: 32″ clear egress door, 36″ halls
- StandardICC A117.1 Type C (visitable)
- StandardICC A117.1 Type C (visitable): a step-free entrance, a WC on its level, 32″ doors
- RecommendationNCIL, AARP and NAHB on visitability
SF-3StairsGraded · 20 of Safety & access's 100 · levels met or not
Its gate, a code's minimum:
SF-3gStairs: the code's sizes- CodeIRC R311.7: 36″ wide, 10″ treads, 7¾″ risers, 12′7″ a flight
- Recommendation7″ risers and 11″ treads (AARP, NAHB)
- CodeIRC R310: 5.7 ft² net, 24″ high, 20″ wide, sill ≤ 44″
- CodeIRC R312.2: an operable sill 24″ up where the drop is over 72″; IBC 1015.8: 36″
The standard
It is a private standard published by Trueinch. It is not an Indian Standard, and not an American National Standard. It is published as these documents, each a page here.
- Part 1: MethodShared by every market: levels and curves, how rooms, checks and parts combine (a weighted geometric mean across the six parts), caps, coverage, uncertainty and the likely range, bands, standing, what a report contains, conformityEdition 1.0, trial use
- Part 2-IN: IndiaIndia's checks and thresholds: NBC 2016 and the city rules; Eco-Niwas Samhita; RERA carpet area; Indian climate zones, room hours and furnitureEdition 1.0, trial use
- Part 2-US: United StatesThe US checks and thresholds: the IRC, IBC and IPMC; the IECC climate zones; ANSI Z765; Fair Housing Act design; US room hours and furnitureEdition 1.0, trial use
- ProceduresHow the standard is kept: comment rounds, the advisory board, editions, interpretations, disputes, quality checks, namesEdition 1.0
Trial use
Edition 1.0 is published for trial use until October 2028. During trial use:
architects' panels in each market validate the score (Part 1 Annex C);
the anchors first fixed on the reference sets (each Part 2's Annex A, 7 October 2026) are fixed again on larger ones, and SP-7's, which the sets can't fix, on a measure of circulation they can;
every value marked to be confirmed is checked against its primary text.
Changes
- October 2026 Edition 1.0 published, for trial use.
- 7 October 2026 The anchors of India's SN-2 and AR-5; the US's AR-5 fixed on the reference sets (each Part 2's Annex A).
- Still provisional The anchors of India's SP-7; the US's SP-7: the reference sets can't fix them yet.
Not here yet
The Procedures have this page name the standard's owner (§1.2) and carry the engines' bench results, the architects' panels and what they find, the interpretations, the advisory board and its advice, and the synopses of comments (§10). None of these is published yet.
Comment, and propose a change
Anyone may comment on the standard or propose a change, at any time, by writing to ceo@trueinch.com. Each is answered as the Procedures set out (§4), and a dispute about a report has its own tracks (§7).