One Job, Two Bases, One Delivery Date
Sixty-two square metres across two rooms, one client, one delivery slot. Half of it is a power-floated slab in a garage that became a family room three winters ago, still wearing the curing compound the ground-worker sprayed on in 1998. The other half is a sand-cement screed in the hall, buried under foam-backed carpet since the house was built and lifted this morning. Same vinyl, same adhesive, same fitter — and almost nothing about the preparation is the same across the doorway.
That is the shape of nearly every luxury vinyl job worth the name. The plank is two to five millimetres thick and stuck down rather than floating, so it inherits the base instead of hiding it. A carpet forgave a trowel ridge, a crumb of screed and a three-millimetre dip. A bonded vinyl tile reports all three, in raking light, in the second week, to the person who paid for it.
There are only four things you can buy to fix a subfloor: a measurement, a moisture barrier, a primer, and a layer of compound. They are not a checklist to work through in order — a sound, dry, flat, absorbent screed needs one of them and a garage slab over wet ground may need all four plus a fortnight. The survey decides, and it is a programme document as much as a specification, because each of the four brings a cure time or a dry-down the fitting date has to sit behind.
Name the Base Before You Test It
Testing a base you have not identified produces a number you cannot act on. A calcium sulfate screed and a cementitious one read differently on different instruments, take different primers, tolerate different compounds and fail in different ways, and telling them apart is a two-minute job on site. Scratch it: a flowing anhydrite screed is softer than a good sand-cement bed and gives up a pale, chalky laitance. Drip dilute hydrochloric acid on a cut edge: cementitious material fizzes, calcium sulfate does not. In European supply the designation comes from BS EN 13813 Screed material and floor screeds — Properties and requirements, CT for cementitious and CA for calcium sulfate, and the delivery ticket usually says so outright if anybody kept it.
Timber decks fail differently again. Plywood and OSB move with humidity, so sheet joints open and close under a bonded floor, and any board that flexes underfoot cracks a levelling compound along the joist line. ASTM F1482 Standard Practice for Installation and Preparation of Panel Type Underlayments to Receive Resilient Flooring covers the overboarding route; BS 8201 Code of practice for installation of flooring of wood and wood-based panels covers the deck itself in UK practice. Either way the questions are the same: every sheet screwed at the stated centres rather than nailed, fixings below the surface, the deck metered dry, and the panel material one the vinyl manufacturer will warrant a bond onto.
Then there is the base that is already a floor. Ceramic tile, terrazzo, old sheet vinyl, thermoplastic tiles, a bonded epoxy from a previous life — each can sometimes stay and each carries its own veto. Bitumen and cutback residues are the notorious one: the plasticisers in a modern vinyl and the residues of a bitumen adhesive attack one another, so the residue is encapsulated with a product rated for it rather than skimmed over and hoped about.
Before any of that is scraped, ground or sanded, settle the asbestos question in writing. Pre-2000 UK floor tiles and their bitumen bedding, and the same generation of product in North America, are a recognised source. In Great Britain the duty sits under the Control of Asbestos Regulations 2012; in the United States removal work is governed by the OSHA asbestos standard at 29 CFR 1926.1101, and the Resilient Floor Covering Institute publishes Recommended Work Practices for Removal of Resilient Floor Coverings for this exact material. None of them permit a grinder on an unsurveyed floor of that age.
| Base | How it announces itself | What it changes downstream |
|---|---|---|
| Power-floated concrete slab | Dense, closed, often glossy; water beads instead of soaking in | Mechanical preparation before anything bonds to it; a non-absorbent primer dilution |
| Sand-cement screed | Fizzes on dilute acid; open texture; sounds solid under a hammer tap | Slow drying from one face; hollow bays and curled edges to map before pricing |
| Calcium sulfate (anhydrite) screed | No reaction to dilute acid; soft surface laitance; usually poured, not floated | Laitance sanded and vacuumed off; a primer system that keeps cementitious compound off it |
| Plywood or OSB over joists | Sheet joints visible; movement or a creak underfoot at a board edge | Refixing, joint treatment and a compound rated for timber — not a slab specification |
| Existing tile, vinyl or resin | A finish, not a base; hollow tiles ring, old vinyl lifts at a cut edge | An asbestos decision first, then a bond test, then encapsulation or removal |
Moisture: the Method Belongs to a Standard, the Pass Mark Belongs to Somebody Else
Most disputes trace back to one misunderstanding here: the standards define how to take the reading, not what reading is acceptable. In-situ relative humidity probes follow ASTM F2170 Standard Test Method for Determining Relative Humidity in Concrete Floor Slabs Using in situ Probes, drilled to a fraction of the slab depth that is deeper for a slab drying from one face than from two, then sealed and left to equilibrate before anybody reads them. Surface emission follows ASTM F1869 Standard Test Method for Measuring Moisture Vapor Emission Rate of Concrete Subfloor Using Anhydrous Calcium Chloride. UK practice more often uses an insulated surface hygrometer box, described in BS 8203 Code of practice for installation of resilient floor coverings, and calcium sulfate screeds across Europe are commonly read with a carbide meter on a drilled sample instead. What constitutes a pass, in every one of those cases, comes from the adhesive and flooring manufacturers, and it is a warranty condition rather than a code requirement.
So the record needs three things and not one: which method, what it read, and whose limit it was measured against. A slab at a given humidity is fine under one adhesive and a claim under another. Note the instrument, the date, the room temperature and the position of every test, and take enough positions to describe the floor rather than to satisfy the form — the practice sets a minimum count scaled to area, and the extra ones you add go where the risk is: against external walls, in the bay that stood open to the weather, either side of a construction joint.
Alkalinity is the reading everyone forgets. A wet slab is an alkaline slab, and a pH high enough to saponify an adhesive destroys the bond long after the humidity has come down to something respectable. ASTM F710 Standard Practice for Preparing Concrete Floors to Receive Resilient Flooring describes the wetted-surface pH method; the acceptable band is printed on the adhesive tin. The taped polythene square everyone learns first, described in ASTM D4263 Standard Test Method for Indicating Moisture in Concrete by the Plastic Sheet Method, is a screening test at best — it can tell you a floor is obviously wet and it cannot tell you one is dry.
When the number fails there are three honest answers and one dishonest one. Wait, and re-test on a date rather than on a feeling. Accelerate the drying with heat, air movement and dehumidification, allowing time between passes for the lower zone to migrate up, because drying a slab from above moves the problem down the page. Or change the specification to a moisture-suppressing system and price it. The dishonest answer is to lay onto a failing reading with a normal primer, and it is dishonest precisely because it works for about eighteen months. ACI 302.2R Guide for Concrete Slabs that Receive Moisture-Sensitive Flooring Materials exists because that decision generates more claims than any other detail in the building.
What a Suppressant Actually Suppresses
A surface-applied moisture mitigation system is a two-component resin film bonded to a prepared slab, holding back vapour driving upward so the adhesive above never sees the drive. ASTM F3010 Standard Practice for Two-Component Resin Based Membrane-Forming Moisture Mitigation Systems for Use Under Resilient Floor Coverings describes the class, and every product in it publishes its own qualifying humidity band. Using a system on a slab reading above its band is not a conservative call; it is outside the product.
It is a vapour system, not a tanking system. Liquid water, a head of groundwater under a slab with no membrane beneath it, a failed damp-proof course feeding the base of a wall — none of those is the same problem, and a resin film a fraction of a millimetre thick asked to hold back liquid under pressure is being asked the wrong question. Where the survey finds standing water or a wet perimeter rather than a high vapour reading, the answer belongs to the waterproofing trade and a different product family.
The detail that gets skipped is continuity, and it is skipped at the edges. A membrane stopping a hand's width short of the skirting line has left an open perimeter for the vapour to find, and it will. The film goes tight into the wall junction, around every penetration, across thresholds, and over the field at the stated wet film thickness in the stated number of coats, the second laid at right angles to the first so a thin pass one way is covered by the other. Coverage rate here is a thickness requirement wearing a spreading-rate disguise: stretching a kit over more area than its rate allows produces a continuous-looking film with no continuous barrier in it.
Then the membrane has to hand a bond on. A cured resin surface is closed, so the system's own broadcast sand or named primer is what gives the compound something to key into; skip it and the compound lifts off in sheets while the membrane stays perfectly stuck to the slab. Mechanical preparation comes first in the sequence, not last — grinding or shot-blasting off laitance, curing compound and old adhesive residue — because a resin bonded to a curing compound has bonded to the thing that will let go.
Cold Slabs and Barriers on the Wrong Side
Not every moisture problem under a vinyl floor comes up out of the concrete. Some of it condenses onto the concrete out of the room. A ground floor over an integral garage, an undercroft or an unheated basement is a cold surface with warm air above it, and during a fit-out with wet trades still running and the heating uncommissioned, the slab can sit below the dew point of the room air for days. Adhesive will not grab, compound blooms, and the hygrometer box is measuring something that was not in the slab yesterday.
Where the build-up carries insulation, the same physics decides where the vapour control layer belongs. The rule is the familiar one — the barrier goes on the warm side of the insulation — and the way it gets broken on floors is specific: a resin barrier is bonded to the slab because that is where resin bonds, insulation boards go over it, and the barrier now sits on the cold side of the insulation. Over a heated space below, that is nothing. Over a garage or an open void in January, it is a condensation plane installed deliberately.
The check below is a steady-state gradient calculation: it places a barrier at a stated fraction of the assembly's thermal resistance and compares the temperature there with the dew point of the room air. It was written for a wall, and using it on a floor takes one honest adjustment — the cold-side temperature is whatever is under the floor, which for a ventilated void or an open garage is close to outdoor design temperature, and for a ground-bearing slab is nothing like it, because ground temperature lags the air by months and never reaches the winter extreme. Use it where that assumption holds; on a ground-bearing floor treat it as a screening exercise and take the answer from a hygrometric assessment instead. BS 5250 Management of moisture in buildings and the psychrometrics in the ASHRAE Handbook — Fundamentals are where the underlying method lives.
Enter the void or garage temperature as the cold side and the room's dew point as the target, and the position of the barrier within the build-up stops being a habit and starts being a number you can put in an email.
The assumed indoor air temperature.
The outdoor winter design temperature for the site's climate zone.
The full wall assembly's total thermal resistance, interior surface to exterior surface.
The portion of the total R-value between the interior face and where the vapor barrier sits.
The dew point temperature of the interior air, based on its temperature and relative humidity.
Temperature at vapor barrier location
55.9 °F
The temperature at this location stays above the interior dew point shown below, so condensation is not predicted under the design conditions entered. No risk predicted under these conditions is not the same as none. The conditions are the ones you entered, and one surface is not the assembly.
- Interior air dew point
- 50 °F
They open the calculator with your figures already in it
Vapor Barrier Dew-Point Condensation Risk Calculator: 55.85 °F — shown in imperial, US market. The link sets both, so the result they see is the one on your screen.
What this calculation does not cover
- Air leakage, not diffusion, is what usually wets a wall, and there is nothing about it here. The gradient gives the temperature at the plane; it cannot say how much moisture arrives there. A wall that passes this check and leaks warm interior air through a top plate, a service penetration or an unsealed electrical box deposits far more water at that plane than vapor diffusion through an intact assembly ever could.
- The R-values entered describe the clear field of the wall, between the framing. The path through every stud, plate and header is colder than this straight line says, and at a steel stud or an uninsulated slab edge much colder — so an assembly that passes in the middle of a bay can be sitting below dew point on the back of the sheathing at every framing member, which is exactly where mold turns up.
- It is one snapshot at one pair of temperatures, and it totals nothing. What damages an assembly is how many hours a year it spends below dew point and whether it dries out in between. A wall that dips below on a few cold nights and recovers is not the same wall as one that stays below for a month, and this returns the identical verdict for both.
- The obvious fix for a failing result can produce a wall that cannot dry. Moving the barrier inboard is right only if the outboard side is open to vapor. Where a low-perm layer already sits outside — exterior foam, a self-adhered membrane, an impermeable sheathing — a second one inside traps whatever gets past either of them, and the assembly then passes this temperature check with no drying path in either direction.
Primer Is Not a Formality
Primer does three unrelated jobs and gets treated as one product because it comes in one bottle. On an absorbent base it stops the compound flash-drying into a weak, dusty crust and stops air rising out of the pores as pinholes. On a closed base it provides adhesion where there is no suction to provide it. And on a calcium sulfate screed it does something chemical: it keeps a cementitious compound from meeting calcium sulfate in the presence of water, which forms expansive ettringite at exactly the interface you need to hold. That reaction is why the primer over an anhydrite screed is a named system from the compound manufacturer rather than whatever is on the van, and why the laitance is sanded off and vacuumed first.
The dilution is decided by the base rather than by the label's default, and the test takes thirty seconds. Drop water on the swept surface in half a dozen places. If it darkens the surface and is gone in a couple of minutes, the base is absorbent and takes the diluted coat, sometimes two on a thirsty screed. If it beads, the base is closed and takes the neat non-absorbent grade — and the porous dilution on a dense slab leaves a glossy film the compound slides across rather than keys into. Beading also flags the other possibility, that the surface is contaminated or still carries a sealer, and that is a grinding decision rather than a priming one.
Primer will not rescue a friable surface. If a coin drawn across the base scores a channel, or a strip of tape lifts a layer of fines, the weak layer is the bond line no matter what is painted over it, and it comes off mechanically. Dust is not housekeeping at this stage either; it is a bond breaker with a coverage rate of its own. Vacuum, vacuum the route the vacuum took, and keep compressed air off the floor entirely — it moves dust sideways into the area you are about to prime.
Levelling: Depth, Strength, and the Second Moisture Clock
Levelling compound is where the money goes and where the estimate is most often wrong, because the eye reads a floor as flat until a straightedge disagrees. Set a datum with a laser and run a grid of readings, recording the depth at each rather than at the worst point. A floor needing three millimetres over most of its area and eleven in one corner is not an eleven-millimetre pour; a floor that dishes gently across every bay can cost more than the corner does, and nobody sees that from the doorway.
Depth is bounded at both ends. Every compound states a minimum and a maximum in a single pass, and the minimum over a non-absorbent surface — a resin barrier, a sealed slab, an existing tile — is thicker than the feather edge people default to, because a thin layer over something offering no suction cures without ever gripping. Beyond the maximum the pour splits into passes at the stated interval, or it cracks and curls at its own free edges. Where the depth needed exceeds what a levelling compound is for, the answer is a screed: different material, different programme.
Strength matters more under vinyl than under anything else, for a reason people find counterintuitive. The plank is thin and transmits point load straight through: a chair castor, a table leg, a fridge corner. What indents is not the vinyl but the compound underneath, and the dent is permanent. The compressive strength class on the bag, the C designation of BS EN 13813, is the number to check against the loading the room will see, and a domestic-grade compound under a commercial castor chair is a callback with a date on it.
The compound is also the job's second moisture clock, and this is the one that eats programmes. Walkable in a few hours is a foot-traffic statement, not a dryness statement — the water in a bulk pour has to leave before a bonded vinyl seals the surface over it, and a thick pour over a resin membrane can only dry upward. Test it the way the slab was tested, against the same manufacturer's limit, and mix to the water ratio on the bag and no more; the extra half-litre that makes it flow nicely is the same half-litre that lowers its strength, raises its shrinkage and lengthens the dry-down.
What a bonded vinyl floor is standing on
- Vinyl plank or tile — two to five millimetres of it, bought by area plus a waste allowance set by the laying pattern rather than by the room LVP, Laminate & Engineered Floor Calculator
- Adhesive bed — trowel notch, open time and slab temperature between them decide whether the bond is wet, tacky or already skinned when the plank lands
- Levelling compound — the layer that takes the base from a tolerance argument to a flat plane; priced on average depth over measured area, not on the deepest reading Self-Leveling Underlayment (SLU) Volume Calculator
- Primer coat — dilution chosen by how the base takes a drop of water; over a membrane it is the named system product or a sand broadcast instead Floor Primer Dilution and Coverage Calculator
- Resin moisture barrier — only present when the moisture reading says so; a wet film thickness in two crossed coats, carried tight into every perimeter Epoxy Flooring Coating Coverage Calculator
- Slab or screed — the only layer nobody buys and the one that decides all the others; identified, tested and mechanically prepared before anything is ordered
Take the grid of depth readings, settle on an honest average rather than the worst corner, and the pour becomes a litre figure that converts to a bag count and a single delivery instead of a mid-pour trip to the merchant.
The total subfloor area to be leveled.
The average thickness of the self-leveling compound pour across the floor.
SLU volume needed
42.1 gal
Actual SLU consumption depends on subfloor roughness/low spots — an uneven subfloor will consume more material than this average-depth estimate suggests. Order 10-15% extra for irregular subfloors.
They open the calculator with your figures already in it
Self-Leveling Underlayment (SLU) Volume Calculator: 42.08 gal — shown in imperial, US market. The link sets both, so the result they see is the one on your screen.
Estimated cost — your price
This site holds no price list for this material — local prices vary too much to publish honestly. Enter your supplier's price and the result is costed with it.
What this calculation does not cover
- Litres do not buy anything. SLU is sold by the bag, and turning this volume into a bag count needs the product's own yield — the litres one bag makes at its specified water ratio — which runs roughly 12 to 16 litres (3.2 to 4.2 gal) from a 25 kg (55 lb) bag and varies enough between products to shift the bag count by 10% or more on the same floor. Take the yield off the data sheet rather than assuming a density.
- The high spot sets the datum for the whole floor, and this takes an average instead. Every SLU has a minimum thickness it will flow and cure at, and you cannot pour thinner than that over the highest point — so nothing on the floor ends up thinner than that minimum and the low corner takes the minimum plus the whole deviation. There is also a maximum lift, above which the pour must be split or extended with aggregate, and adding aggregate changes the yield again.
- Primer is a separate material with its own coverage rate, and skipping it is how a pour fails rather than how it saves money. A porous slab pulls water out of the compound and pinholes; a sealed or non-porous substrate gives it nothing to grip. Porous slabs often take two coats, and the primer rate per square metre has no relationship to the pour depth calculated above.
Where a Roll Still Goes Down, and Where It Must Not
Glue-down vinyl takes no underlay. The point of a bonded floor is that it has nowhere to go, and a resilient layer beneath gives every plank a spring to work against — joints roll open under a rocking load and the adhesive fails in shear. Where a specification calls for both a bonded vinyl and an acoustic mat, the mat is a bonded acoustic layer designed for that build-up, not a foam roll from the laminate aisle.
Click and rigid-core vinyl is where a roll is genuinely part of the build-up, and even then the product is narrow: a thin, dense, low-compressibility mat, because an over-soft foam lets the panel deflect at the joint until the locking profile breaks. The maker's maximum thickness and compressibility limit are the specification. Separately, in flats an impact-sound layer may be a condition of the lease or of the building regulations — Approved Document E, Resistance to the passage of sound, in England, with laboratory performance measured to BS EN ISO 10140 and site performance to BS EN ISO 16283. A laboratory figure on packaging is not a site result, and where pre-completion testing applies it is the site result that counts.
Whichever product it is, it is counted in rolls rather than square metres and the two numbers rarely agree. Rolls come in fixed widths and lengths, laps and turn-ups eat coverage, an offcut is useful only if it still spans a full run, and the running direction the flooring manufacturer requires can change the count on a narrow corridor. One thing an underlay never is, in any of these cases, is a moisture remedy: a film-backed underlay is a vapour retarder inside a floating build-up, and it has nothing to say to a slab that failed a humidity test.
Work the count from the room and the roll size on the actual product rather than dividing the floor area by a remembered figure, because the roll that goes down last is the one that turns out to be two metres short.
The total floor area to be covered with underlayment.
The area a single roll of underlayment covers, per the product's packaging.
Underlayment rolls needed
5 rolls
They open the calculator with your figures already in it
Laminate/Vinyl Plank Floor Underlayment Roll Calculator: 5 rolls — shown in imperial, US market. The link sets both, so the result they see is the one on your screen.
Estimated cost — your price
This site holds no price list for this material — local prices vary too much to publish honestly. Enter your supplier's price and the result is costed with it.
What this calculation does not cover
- The area does not tell you whether you need any rolls. A great many laminate and click-LVP boards ship with a pad already bonded to the back, and adding a separate underlayment beneath one of those stacks two cushions under a click joint — the joint over-flexes, the tongue works loose and the seams gap. Most makers void the warranty for it outright, so check the back of the board before ordering the roll.
- Coverage area says nothing about the moisture side of the job. Over a concrete slab on or below grade, what governs is the underlayment's vapor rating — a 6-mil polyethylene film or a combination product with an integral barrier, lapped and taped and turned up the wall — and a plain foam roll of identical square footage provides none of it. The slab wicks, the planks cup, and it reads afterwards as a flooring fault.
- A thicker roll is not a leveling compound. Underlayment bridges a hollow rather than filling it, and the flatness most board makers actually require is on the order of 3 mm (0.12 in) under a 2 m (6.5 ft) straightedge. Foam laid over a dip lets the plank rock on every step and the click joint is the part that breaks — grind the high spots and fill the low ones before any of this goes down.
Flatness, and What Vinyl Reports That Carpet Hid
Surface regularity has named classes, and quoting them turns an argument into a specification. UK practice uses the SR classes of BS 8204-1 Screeds, bases and in situ floorings — Concrete bases and cementitious levelling screeds to receive floorings, expressed as a maximum deviation under a two-metre straightedge, the tightest class reserved for thin, unforgiving finishes. North American practice uses the F-numbers of ASTM E1155 Standard Test Method for Determining FF Floor Flatness and FL Floor Levelness Numbers. Survey against whichever applies, record the deviations, and issue them before taking possession of the area — a fitter who lays onto an out-of-tolerance base has, in practice, adopted the tolerance.
What makes vinyl unforgiving is thickness. A two-millimetre trowel ridge under a two-and-a-half-millimetre tile is a visible line. So is a screed crumb, a proud fixing head, a grout joint in the tiles left underneath, a plywood sheet edge, and a repair patch finished flush with a filling knife but not with the floor. Low-angle daylight finds every one of them, which is why the walk-through that matters happens at the end of the day with the lights off rather than under a work lamp.
Cracks want a decision rather than a covering. A static shrinkage crack is routed out, filled with resin or rapid mortar and levelled over. A crack still moving, or a designed movement joint, has to be carried up through the finish — compound taken across a moving joint cracks in a straight line and takes a strip of vinyl with it, and no thickness prevents that. Where a base is cracked but sound and the movement small, a crack isolation layer is a specific product with a specific extent, not a reason to pour more compound.
The Order the Site Actually Runs In
Every intervention above carries a hold point, and the failures on this work are almost never technical ignorance — they are two operations swapped in the programme. Grinding after priming. Levelling before the moisture result. A suppressant applied to a slab that still has curing compound on it. The sequence below is the one the hold points impose, and the only place it flexes is at the front, where a base identified early buys the option of a re-test date that still lands before the delivery.
Keep the record as you go, because a resilient floor claim is argued from paper long after the site is handed back: photographs of the prepared base before the membrane, moisture readings with instrument and date, primer and compound batch numbers, the compound's own dry-down test, and the manufacturer's instruction sheet as printed for that batch.
- Identify the base and settle the asbestos question before any mechanical work is planned.
- Survey flatness against the class the specification names, and issue the deviations before taking the area over.
- Test moisture and pH by the method the specification calls for, against the adhesive manufacturer's limits, and record instrument, position and date.
- Prepare mechanically — grinding or blasting off laitance, curing compound, old adhesive residue and any friable layer.
- Apply the moisture mitigation system only where the reading requires it, at its stated film thickness and crossed coats, and give it its own cure.
- Prime to the dilution the water-drop test indicates, or broadcast sand into the membrane where the system specifies that instead.
- Pour levelling compound to the average depth measured, mixed to the printed water ratio, split into passes where the depth exceeds one lift.
- Let the compound dry to the flooring manufacturer's limit and prove it with a test, not with a calendar.
- Condition the room and the stock to service temperature, then lay.
What the survey has to come back with
The six findings that decide whether this floor is a two-day fit or a three-week preparation contract, in the order the survey collects them.
- Base type and age — Cementitious or calcium sulfate, timber or existing finish — with the asbestos position settled in writing for anything pre-2000.
- Moisture reading and its owner — Method, instrument, positions, date, and the adhesive manufacturer's limit it is being measured against; alkalinity alongside it.
- Deviation grid — Depth readings on a grid against a laser datum, giving an average pour depth and a worst point, not one number from the doorway.
- Mitigation area — The area needing a resin barrier, priced at its wet film thickness in crossed coats, with perimeters and penetrations counted in.
- Compound strength class — The BS EN 13813 C designation matched to the point loads the room will carry, not the cheapest bag that levels.
- Underlay decision — None at all for glue-down; for a click product, the thickness and compressibility the maker allows, counted in rolls and not in square metres.
Opens the calculators above on one screen with the dimensions from this article already filled in. Quantities only — this site publishes no price list, because local prices vary too much to publish honestly.