Fenetres Coulissantes en Aluminium Wholesaler in China: Baie Vitre Coulissante, Galets, Drainage et Prix FOB

Why a Fentre Coulissante en Aluminium Is a Rolling System, Not a Glazed Frame

A casement sash hangs on friction hinges and compresses its seals. A sliding leaf does neither. Its entire dead load sits on two roller carriages running on a bottom rail, and its seals are brushes or sliding wipers that never compress. That single difference explains why sliding products sit two to three classes below casement on EN 12207 air permeability and one to three classes below on EN 12208 water tightness, even when both are built from the same extrusion and the same glass.

Load path: glass, sash, carriage, rail, slab

The chain is short and every link is quantifiable. Glass dead load goes into the sash rabbets, the sash rails carry it to the two stiles, the stiles deliver it to the two roller carriages under the bottom rail, and each carriage spreads it over its wheels into the rail. The rail delivers it to the frame, the frame to the anchors, the anchors to the slab. There is no redistribution path: if the bottom rail is not level, the load does not find another route, the leaf simply drags.

Load per wheel applies a dynamic factor of 1.5 to the static weight. That factor is not a safety margin; it is the measured impact when a wheel crosses a rail joint, a screw head or a grain of sand. Four wheels are assumed: two carriages of two wheels. A single-wheel carriage doubles the per-wheel load and with it the contact stress.

Why the load number matters more than the mass number

The acoustic build-up 6-16Ar-44.2 turns a standard 1 200 x 2 150 leaf from 63.4 kg into 97.5 kg, a 54 % increase, purely from glass specification. Nothing else in the order changes on paper, but the per-wheel load goes from 233 N to 359 N and the roller specification moves up one or two grades. On the large 1 500 x 2 400 leaf the same glass choice takes the leaf to 135 kg and 496 N per wheel, which is outside the rating of every nylon-bushed roller on the market. This is the single most common specification error on fentres coulissantes en aluminium: the glazing is upgraded for acoustics, the carriage is not, and the rollers fail in year two.

Roller Selection: Contact Stress, Material and L10 Life

Roller selection has two independent limits. The first is Hertzian contact stress between the wheel and the rail, which decides whether the rail dents. The second is bearing fatigue life, which decides nothing at all in practice – the numbers below show why.

Hertz contact stress against a bare aluminium rail

Treat the wheel as a cylinder of radius R and contact width b = 8 mm running on a flat rail. With equivalent modulus E* from the two materials, the half-width of the contact patch is a = sqrt(8FR / (pi b E*)) and the peak pressure is p = 2F / (pi a b). Against a bare 6063-T6 aluminium rail the equivalent modulus is 39 277 MPa for an aluminium wheel and 58 605 MPa for a steel wheel. The rail yields at 170 MPa.

Peak contact pressure, MPa – POM

Peak contact pressure, MPa – PA66 GF25

Peak contact pressure, MPa – Aluminium 6063-T6 rail

Peak contact pressure, MPa – Steel wheel / rail

Read the steel row first. A 28 mm steel wheel at 450 N per wheel produces 194 MPa on the rail, above the 170 MPa yield of 6063-T6. At 650 N it reaches 233 MPa. The wheel does not fail – the wheel is steel – but the rail takes a permanent groove, and after a few thousand cycles every wheel passing over that spot takes an impact. This is why a steel-wheel specification is incomplete without a stainless rail insert, or without going to a 50 mm wheel where 450 N returns 145 MPa. The insert costs 7 – 11 USD/m2 and is the cheapest insurance on the whole system.

Polymer wheels invert the problem. POM at 28 mm and 450 N gives 44 MPa, well under the 90 – 110 MPa compressive strength of the material, so the wheel survives and the rail survives. PA66 GF25 is stiffer (E* 4 814 MPa) and therefore concentrates more: 56 MPa at the same load, still acceptable, but with less margin and a harder, noisier ride. Polymer wheels fail by flat-spotting when a leaf is left parked for a season, and by moisture absorption in a coastal climate, not by exceeding contact stress.

L10 bearing life, and why it is not the governing limit

L10 = (C / P)^3 x 10^6 revolutions, where C is the dynamic load rating of the bearing and P the per-wheel load. A 1 100 mm travel gives about 25 revolutions per open-and-close cycle for a 28 mm wheel. At eight cycles a day that is 2 920 cycles per year.

For a standard leaf every usable roller returns a fatigue life measured in centuries. That is not a modelling error, it is the correct conclusion: bearing fatigue never governs a window roller. What governs is contamination, corrosion, flat-spotting and rail damage. A sealed bearing buried in track dust and salt fails in five to eight years regardless of a 355-year L10. Two specification consequences follow, and they are cheap:

• Sealed bearings beat open ones. A 2ZZ metal shield keeps the factory grease in and the mortar dust out. The price difference is under 1 USD per carriage.
• Ask for the rail, not just the wheel. A stainless insert on the bottom track costs 7 – 11 USD/m2 and removes the only failure mode that destroys the frame rather than a serviceable part.
• Park position matters. Polymer wheels flat-spot if the same leaf sits in the same position for months. On a showroom or a seasonal residence, specify PU-coated or steel wheels with the rail insert.
• Adjustment access is a design decision. A carriage adjustable through the leaf stile can be re-levelled in five minutes. One that requires lifting the leaf out needs two fitters and an hour.

Rail, Drainage and Water Tightness on a Sliding Track

A sliding bottom rail is a gutter that also happens to carry a wheel. Water that gets past the outer brush must be collected, moved sideways to a weep slot and expelled, without ever reaching the inner track. Getting that wrong is the source of most EN 12208 failures on fentres coulissantes en aluminium.

Slot capacity against a real spray rate

EN 1027 and EN 12208 test at roughly 2 L/min/m2 of spray. On a 2 400 x 2 150 opening – 5.16 m2 – that is 10.3 L/min landing on the frame, and 15.5 L/min at a 3 L/min/m2 driving-rain assumption. Flow through a rectangular slot is Q = Cd A sqrt(2gh), with Cd about 0.62 and h the water head standing in the chamber, typically 25 to 50 mm.

A 5 x 12 mm slot, which is what most factories punch as standard, passes 1.56 L/min at 25 mm head. The test demands 10.3 L/min. Four slots gets you there on paper; in the field, two of them will be blocked by mortar within a year, so the design capacity has to be built with redundancy, not with the minimum. The practical rule is to size for the 3 L/min/m2 case and then double the slot count.

Pressure equalisation and the two-chamber rule

Water tightness classes above about 4A on a slider are not achieved by better brushes. They come from pressure equalisation: an outer chamber open to the outside so that wind pressure acting on the leaf is not pushing water across the inner seal, and an inner chamber drained independently. The two chambers must not share a drain path, because a shared path lets the pressure pulse from the outer chamber blow water into the inner one.

• Outer chamber: drained directly to the outside face, slots at 300 – 400 mm centres, minimum 5 mm clear width.
• Inner chamber: drained through a separate channel, with a baffle or a one-way flap so a wind gust cannot reverse the flow.
• Roller track: drained to the outer chamber only. Water in the wheel track is the number one cause of bearing corrosion.
• Rail joint: sealed with butyl and a mechanical splice. A butt joint with silicone alone opens after one thermal season.
• Level tolerance: 1 mm per metre. Beyond that the leaf will not self-drain and will not run true, and no amount of carriage adjustment fixes it.

The result of getting this right is visible in the class table. Inline sliders land at 3A – 5A. Lift-and-slide, which can compress a full perimeter gasket when closed, reaches 6A – 8A. That is the entire commercial argument for lift-and-slide, and it is worth 40 – 60 USD/m2 on a project with an exposed west elevation.

Baie Vitre Coulissante: Subdivision, Span and Interlock Deflection

A baie vitre coulissante is where sliding systems stop behaving like windows and start behaving like frames. At 2 400 mm leaf height and above, the controlling member is no longer the bottom rail – it is the interlock, the vertical meeting stile where the sliding leaf closes against the fixed leaf. It spans the full leaf height with nothing supporting it in between, and it carries the wind reaction from the leaf.

What the deflection limit actually is

Standards give L/200 or L/300, which at 2 400 mm is 12 mm or 8 mm. Neither is the real limit. The real limit is the seal engagement tolerance of the interlock: the hook-and-flange geometry plus its brush or bulb seal has about 8 mm of working engagement. Deflect the interlock more than that and the brushes separate, wind-driven rain walks straight through the joint, and the two leaves visibly rack against each other. Eight millimetres is therefore the design number, and it governs before L/200 does on any leaf taller than 1 600 mm.

The consistent finding across every section in the table is the same one we see on garage doors and greenhouses: deflection governs, not strength. At the 8 mm limit the bending stress in the interlock is a small fraction of the 155 MPa allowable for 6063-T6. The member is not close to breaking; it is simply too flexible. Which means the fix is always a stiffness fix, and stiffness is bought with depth, not with wall thickness.

The table gives the maximum leaf height for each interlock at a 600 mm tributary width feeding it. Read the 1.0 kPa column, which is a typical French zone 3 value with a modest height factor: a 30 x 40 x 1.6 mm interlock is exhausted at 1 367 mm, so it is simply not usable on a full-height leaf. A 40 x 70 x 2.0 reaches 2 118 mm, and 45 x 90 x 2.2 reaches 2 573 mm.

Required interlock section by leaf height and wind zone

French wind zones map directly onto these columns: zone 1 at 0.32 kPa sits below the 0.5 kPa column, zone 2 at 0.39 kPa likewise, zone 3 at 0.47 kPa is effectively 0.5, zone 4 at 0.56 kPa is between 0.5 and 1.0, and a coastal or elevated site with a height factor lands at 1.0 – 1.5. So a 2 400 mm leaf in La Rochelle or Sete needs a 45 x 90 x 2.2 interlock, and a 2 700 mm leaf in an exposed Corsican site needs 50 x 110 x 2.5 or better.

French practice adds one more constraint. The standard French baie dimension is a 2 400 x 2 150 rough opening for a two-leaf slider, and the leaf is usually split 1 200 / 1 200. If the architect asks for a wider opening, the correct answer is almost always three leaves rather than two wide ones: three 1 000 mm leaves keep every interlock in the I1 – I2 range and let you pass a 1 000 mm clear opening, which matters for furniture and for PMR circulation.

Coulissant Classique, a Levage, ou a Galandage

Three mechanisms carry the French market for a fenetre coulissante or a baie, and they are not interchangeable. The choice is made at extrusion stage and cannot be changed on site.

Inline, lift-and-slide and pocket: seven-point comparison

The commercial decision is entirely in rows two, three and six. If the project sits on an exposed elevation, or the specification calls for class 6A or better, inline cannot get there and the lift-and-slide premium is not optional. If the project has a PMR (personnes a mobilite reduite) requirement, the flush threshold matters more than the class, and galandage is the only mechanism that genuinely reaches 0 – 5 mm – at the cost of a wall cassette that is permanently inaccessible.

Galandage: what the pocket costs you

A galandage cassette is built into the wall, which means it is decided before the wall is closed and it is never serviced afterwards. Three consequences:

• No thermal break at the pocket. The cassette is a box inside the insulation layer. Unless the pocket is insulated on the outer face, the closed leaf is sitting in a cold box and the Uw calculation for the opening is meaningless as a whole-unit figure.
• Roller access is from above only. The top-hung variant allows leaf removal; the bottom-rolling variant usually does not. Specify top-hung for anything over 120 kg.
• Sealing at the pocket mouth is a single line. There is no second chamber, so water tightness caps out around 5A regardless of how good the leaf is.
• Cost is per leaf, not per m2. 85 – 140 USD/leaf on top of the frame – the single largest option adder on this page.

Thermal and Acoustic Performance of a Sliding System

Because a baie is one big panel rather than a grid of small ones, the glass share is high. On the 2 400 x 2 150 reference opening used here, glass is 4.019 m2 of 5.16 m2 – 77.9 %. That single fact decides the whole thermal strategy: on a casement you can win with the frame; on a slider you cannot.

Uw matrix: polyamide strip width x glazing x spacer

Uw from EN ISO 10077-1 for the reference opening, with glass perimeter lg = 11.96 m and one vertical interlock of 2.15 m at Psi = 0.18 W/mK. Frame Uf from the fitted curve Uf = 4.949 exp(-w/18.0) + 0.951, which tracks published system data from 0 to 34 mm.

Two things fall out of the matrix. First, across the whole strip range 0 to 34 mm, Uw moves by 0.93 to 1.09 depending on glazing. Second, across the glazing range at a fixed 34 mm strip it moves by 1.46 (2.55 float to 1.09 triple). Glazing is worth roughly 1.5 times the frame on a sliding unit. And the cost runs the same way: Low-E coating is 12 – 18 USD/m2, while taking the frame from a 14 mm to a 34 mm strip is 24 – 58 USD/m2 and it makes the profiles deeper, the leaf heavier, and the rollers bigger.

Warm edge, and the air permeability ceiling

Warm edge buys 0.10 to 0.13 W/m2K for 6 – 9 USD/m2, which is roughly 60 – 90 USD per unit of U. For the same money Low-E coating buys about ten times that improvement. Warm edge is therefore not a U-value purchase – it is a marginal-edge condensation purchase. On a slider it is worth having anyway, because the glass edge on a 2 m tall leaf is exactly where a French winter produces a visible condensation band at 40 % RH.

On air permeability there is no way around the mechanism. A sliding leaf cannot compress a gasket; it can only wipe against a brush or a sliding fin. EN 12207 class 4 needs a leakage figure that a perimeter brush simply does not deliver. Class 2 – 3 is the honest expectation for inline and class 3 – 4 for lift-and-slide. Any supplier claiming class 4 on an inline slider should be asked for the test report page, and then for the size of the tested specimen.

Acoustics follow the same logic as the seal: the leaf is fine, the gap is not. A 1 mm continuous gap at the interlock is 0.30 % of the opening area and it drops a Rw 40 dB assembly to about 25 dB. On a slider the interlock is a 2.15 m long seam, so the specification has to name the interlock seal system – double brush with a central fin, or a compressible bulb on a lift-and-slide – not just the glazing build-up. Our soundproof window notes cover the gap arithmetic in more detail.

Double Vitrage et Moustiquaire sur un Coulissant

The most searched French configuration is the fenetre en alluminium double vitrage avec moustiquaire – a sliding aluminium window with an insect screen. It is also the one that is most often quoted wrong, because the screen and the glazing each change a different subsystem and neither appears on the glazing line of the quote.

Glazing weight is a roller specification, not a comfort option

The table below is the same leaf at three sizes with five glazing build-ups. Nothing but the glass changes, and the per-wheel load moves by more than a factor of two across the range.

At 1 800 x 2 500 the acoustic build-up produces 135 kg and 496 N per wheel. That requires R5, a 34 mm PU-coated twin wheel. The quote for that leaf usually still shows the standard R2 carriage, because the roller line is a default in the ERP system and the glass line is what the salesperson edited. Ask explicitly: “what is the carriage rating on the acoustic leaves?” and get it in writing.

Two glazing details matter specifically on sliders. First, argon retention: EN 1279-3 limits leakage to 1 % per year, so a unit is at about 78 % fill after 25 years and Ug has moved from 1.08 to roughly 1.13. The U-value is fine; the failure mode is desiccant saturation and fogging, which arrives long before the thermal figure degrades. Second, altitude: a unit sealed at 5 m in Foshan and installed at 1 200 m or above sees a pressure differential of about 14 kPa and will pillow outward. Over 1 200 m of elevation change specify a capillary breather tube at 2 – 4 USD/m2.

Moustiquaire on a slider: four forms, one trap

Mesh geometry matters more than mesh count. Open area is (aperture / pitch) squared. An 18 x 18 mesh at 0.23 mm wire gives 70.1 % open area; the same 18 count at 0.28 mm wire drops to 64.3 %, which is a 6 % loss of daylight and ventilation for no gain in insect exclusion. A 20 x 20 at 0.18 mm gives 73.7 % and is the best optical trade available, but the wire is fragile. In a C4 or C5 coastal atmosphere, aluminium mesh is anodic against the frame – use 316 stainless.

Porte Coulissante en Aluminium: Seuil, PMR et Condamnation

A porte coulissante en aluminium is the same mechanism as a fenetre coulissante with three extra constraints: a person walks through it, it is usually the accessible entrance, and it is the door an intruder tries first.

Threshold height, and what PMR actually requires

French accessibility rules work on a ressaut of 20 mm maximum, or 40 mm if it is chamfered at 1:2 or less. A standard inline slider needs a 25 – 45 mm threshold to reach class 7A – 8A, which puts it in direct conflict with PMR. The resolution used on most French projects is a lift-and-slide at 20 mm with a linear drain set into the terrace immediately outside – the drain is doing the water work the threshold would otherwise do. Budget 30 – 55 USD per linear metre of drain and specify it with the door, not with the landscaping.

Locking and security on a sliding leaf

• Multi-point hook lock. A single espagnolette is the minimum; three to five locking points on a 2 150 mm leaf keeps the interlock engaged under wind reversals as well as under attack.
• Anti-lift device. A sliding leaf can be lifted out of its track from outside. A simple anti-lift block at the head costs a few dollars and removes the most common forced-entry method on French sliding doors.
• Cylinder to EN 1303. Grade 4 minimum for a ground-floor residential door; grade 5 or 6 with a key-retaining function for a commercial opening.
• EN 1627 RC classification. RC2 is the practical residential target. Note the N suffix: RC2N means the glazing was not attack-tested, which on a 78 % glass sliding door makes the N variant almost meaningless. Ask for RC2, not RC2N.
• Interlock engagement depth. Minimum 12 mm of hook overlap. Below that, negative wind pressure can pull the two leaves apart at the meeting stile.

Normes et Certification France: What to Ask For

French specification language is precise and the documents are not interchangeable. A French CCTP for fentres coulissantes en aluminium will reference four things, and they do different jobs.

AEV classification, and the A/B series trap

CE marking, NF CSTB, CEKAL, Acotherm

• CE / DoP under EN 14351-1. Mandatory. AVCP System 3 for a standard window. The DoP lists the tested values – check the tested specimen size, because a sliding door DoP based on a 1 200 x 1 500 specimen does not cover a 2 400 x 2 400 baie.
• NF CSTB (NF Fenetres, NF Menuiseries). Voluntary, widely required on French public and social housing work. It audits the factory, not just the product. Budget 1 400 – 3 600 USD per project for the dossier.
• CEKAL. Certification of the glazing unit itself, not the frame – argon retention, dew point, and the acoustic or security classification of the IGU. It is the document to ask for when the complaint is fogged units.
• Acotherm AC1 – AC4. The French thermal-acoustic label: it gives a single Uw-based thermal class and an acoustic class, which is what a MaPrimeRenov or a CEE dossier expects to see. Registration runs 900 – 2 400 USD per project.
• DTU 36.5 and NF DTU 36.5 P1-2. The installation rules, including the three pose types – applique, tunnel and feuillure – and the joint treatment. This is the document the installer works to, not the supplier.

One trap worth naming explicitly: the CCTP must state which dimension is being measured. French practice recognises the trou nu de maconnerie (structural opening), the precadre (pre-frame built into the masonry), the dimensions finies (finished frame) and the cote d encombrement (overall envelope). Measuring the structural opening and cutting to finished frame size produces a 40 – 60 mm error that cannot be corrected on site. Our fentre aluminium specification notes and fenetre coulissante sizing page both carry the dimension tables in full.

Manufacturing Sequence and Inspection Points

Ten operations, and one of them is not ours. The sequence below is a Foshan factory running 6063-T6 profiles with a polyamide strip; the buyer-controlled step is called out because it is the only one with real schedule leverage.

Process steps and where the time goes

Total shop time is 25 days. Add 7 days for drawing approval and the order cycle is 32 days. Drawing sign-off is 21.9 % of the elapsed time and it is the only step a buyer controls. Everything else is either machine time or a queue. If the schedule slips, it almost always slips there.

Inspection points that catch real defects

1. Shear test on the crimped strip, per die batch. The polyamide knurl groove is held to about +/- 0.05 mm. A groove worn 0.1 mm over stops gripping, and the failure is delayed: the leaf passes every pre-shipment check and drops or binds after one heating season. Ask for the report per die batch, not per profile series.
2. Dry-build one unit per specification, photograph it. This single step catches more errors than all the others combined. The most common is a glazing unit ordered at 32 mm into a 28 mm rebate – invisible until assembly.
3. Rail flatness, 1 mm per metre. Measured on the assembled frame, not on the extrusion. A frame racked in the crate will not run true no matter how the carriages are adjusted.
4. Operating force to EN 12046-1. Recorded per leaf. On a lift-and-slide, above 80 N on the handle means the carriage height is set wrong or the rail is out of level.
5. Drain path test. Water poured into the outer chamber must exit at the slots within a few seconds and must not appear in the inner chamber. This is a ten-second test and it is the one that predicts the year-two call-back.
6. Coating thickness and adhesion. 60 – 80 um for Qualicoat Class 1, cross-cut adhesion to ISO 2409 class 0. Pre-treatment is what actually controls corrosion, not the powder thickness – a zirconium-titanium conversion coating outperforms iron phosphate by a wide margin in salt spray.
7. EN 14179 heat soak. 4 – 7 USD/m2. Nickel sulphide inclusions break about 0.1 – 0.2 % of toughened panes. On a 200 m2 project that is roughly one unexplained breakage per year if it is skipped.
8. Glass edge clearance and setting blocks. Without blocks the unit slides down in the rebate and the bottom edge chips a season later.

FOB Pricing, Options and Commercial Terms

FOB Foshan or Shenzhen, per m2 of finished opening, for fentres coulissantes en aluminium. Prices are for a two-leaf baie at 2 400 x 2 150 with standard R2 – R3 carriages, Qualicoat Class 1 powder in a stock RAL, and standard export crating.

FOB matrix by configuration and volume

The C1 to C2 step is 22 USD/m2 and buys a 24 mm strip and Low-E. The C2 to C3 step is 40 USD/m2 and buys the lift-and-slide mechanism – sealed perimeter gaskets, 200 – 400 kg leaf capacity, and two to three water-tightness classes. That is the steepest but also the most defensible jump on the sheet, because it is the only one that changes the failure mode rather than the magnitude.

Option adders

Standard commercial terms:

Container Loading and Landed Cost to France

Sliding units are bulky and light. That combination determines the whole logistics strategy and it is the opposite of what applies to glass doors or stone.

40HQ loading arithmetic

The container fills on volume at 99.2 % and reaches only 49.1 % of the payload. Two consequences. First, knock-down does nothing: glass cannot be nested, so a KD slider is the same volume as an assembled one. The real lever is crate engineering – better stacking takes a container from 220 to 260 m2 of product and cuts freight per m2 by about 15 %. Second, because there is unused payload, sliding units are the ideal partner cargo for a heavier product from the same factory; a consolidated container typically runs 8 – 12 % cheaper per line item than two separate shipments.

Landed cost, Le Havre

Delivered and installed at 244.9 USD/m2 against a local benchmark of 340.0 is a saving of 28.0 %.

Duty and anti-dumping sensitivity

Installation Sequence and Failure Modes

Sliding units fail in year two, and they fail for reasons decided in year zero. Four of the six failure modes below are specification decisions, not workmanship.

Eight-step installation

1. Check the structural opening. Confirm which French dimension base the frame was cut to. Diagonal tolerance 3 mm over 2 400 mm; a racked opening cannot be corrected with packing shims beyond about 5 mm.
2. Set the pre-frame or the sub-sill with a fall to the outside. Minimum 1 %. A level sub-sill guarantees standing water in the outer chamber.
3. Apply the air and vapour seal. For a French installation, a vapour-open external tape with a sill membrane turned up at the ends. Silicone alone on the external perimeter is the most common cause of year-one leaks.
4. Anchor the frame. Anchor through the frame into the structure, never through the polyamide strip – a screw crossing the strip is a thermal bridge and a corrosion path. Anchor spacing 400 – 600 mm, within 150 mm of each corner.
5. Verify rail level at 1 mm per metre before the leaves go in. Use a spirit level on the rail itself, not on the frame head.
6. Hang the leaves, then set carriage height. Adjust so the leaf is plumb and the interlock overlap is at least 12 mm top to bottom.
7. Test the drain path. Pour water into the outer chamber; confirm discharge at the slots and no water in the inner chamber. Repeat on every unit – one blocked slot in ten is normal straight out of the crate.
8. Commission the mechanism. Record the operating force to EN 12046-1, cycle the leaf ten times, retorque the handle and the lock keeps.

Six failure modes

Project Data: Two French Deliveries

Lyon, 68 units – residential renovation, zone 2

A 1970s block, 68 two-leaf baies at 2 400 x 2 150, replacing single-glazed aluminium sliders. Wind zone 2 at 0.39 kPa, leaf height 2 150 mm, so the interlock requirement falls between the I1 and I2 columns at 0.5 kPa: I2 at 35 x 55 x 1.8 was specified with margin. Glazing 4-16Ar-4 Low-E on a 24 mm strip with an aluminium spacer, Uw 1.57 as delivered.

The one decision worth flagging: the project used inline rather than lift-and-slide to save about 40 USD/m2, and accepted 4A instead of 7A. That was correct here – the elevation is sheltered and the block is inland. On the same budget, a coastal site would have needed the lift-and-slide regardless.

La Rochelle, 24 units – coastal, zone 4

A seafront development 300 m from the water, wind zone 4 at 0.56 kPa with a height factor pushing the design case to roughly 1.0 kPa. Leaf height 2 400 mm, which puts the interlock at I4 (45 x 90 x 2.2). Lift-and-slide specified for the water class, with a 20 mm PMR threshold and a linear drain set into the terrace.

Two things were added late and both paid for themselves. The stainless rail insert was 9 USD/m2 and removes the only failure mode that would have destroyed frames. The A4 fasteners were a few hundred dollars and are the difference between a five-year and a twenty-year coastal installation; aluminium at -0.85 V is anodic to every bare steel fastener in the assembly.

Comparatif: Sliding Against the Alternatives

Every comparison table on this site ends up answering the same question, which is not “which is better”. It is “which constraint decides”. The table below is the honest version for a fentre coulissante.

Ten-point comparison

What the comparison actually decides

Read the table by constraint, not by row. Four questions settle it, and they come in this order:

• Is the elevation exposed? If the CCTP calls for class 6A or better, inline is out and the lift-and-slide premium is mandatory, not optional.
• Is it the accessible entrance? If PMR applies, a 20 mm or 5 mm threshold is required, which points to lift-and-slide or galandage. A 45 mm inline threshold with a bolted ramp is a non-compliant answer that gets rejected at reception.
• Does the leaf exceed about 1 800 x 2 400? Above that, inline carriage ratings run out and lift-and-slide is the only mechanism with the capacity.
• Is the wall available? If you cannot build a pocket, galandage is not on the table no matter how attractive the 100 % clear opening looks.

Where none of those bind, an inline slider is the correct choice and the cheapest. Where one binds, the comparison collapses to a single row and the decision takes thirty seconds. If acoustics and thermal performance are the priority and the opening is small, a casement is still better on every performance line and our casement window data is the right place to compare. For a wide opening where stacking is acceptable, folding door systems give a larger clear opening than any slider.

RFQ Checklist

An enquiry that contains the eight technical and eight commercial items below gets a priced answer in one pass. An enquiry that omits them generates two weeks of questions, and the missing item is almost always the one that changes the price.

Technical – what to specify

1. Opening dimensions and the dimension base. State trou nu de maconnerie, precadre, or dimensions finies. A 40 – 60 mm ambiguity here is the most expensive omission in the list.
2. Number of leaves, and which one slides. Two-leaf, three-leaf, and the direction of slide relative to the interior.
3. Wind load, not wind zone. Give the pressure in Pa or kPa with the height factor applied. “Zone 3” leaves the supplier guessing at the building height.
4. Required AEV class, and the series. “Class 7A” and “class 6B” are different products. State which one the CCTP demands.
5. Glazing build-up and required Ug. Include laminate, acoustic, and whether heat soak is required.
6. Polyamide strip width and target Uw. State the Uw, not just the strip; the supplier may reach it a cheaper way.
7. Threshold height and PMR requirement. Determines the mechanism.
8. Screen, coating class and colour. Moustiquaire type, Qualicoat class, RAL reference, and the ISO 9223 corrosivity category of the site.

Commercial – what to confirm in writing

1. Quantity in m2 and in units, per configuration. Volume pricing is per configuration, not per order.
2. Whether certification is included. NF CSTB, CEKAL, Acotherm. Say explicitly “included” or “excluded” and the comparison becomes honest.
3. Roller rating in newtons per wheel for each leaf size and glazing option in the order. This is the line that decides the year-two call-back.
4. Rail specification. Bare aluminium or stainless insert.
5. HS classification and the exporter anti-dumping rate. Written, before shipment. It is worth more than every product option on the sheet combined.
6. Incoterm, port and lead time. FOB Foshan vs FOB Shenzhen is a real difference in inland cost.
7. Payment terms and whether LC is required.
8. Spare parts percentage and warranty period per component. Profiles, coating, hardware and IGU have different periods; a blanket “10 years” is not a warranty.

Related Systems

Sliding systems

• Fenetre coulissante from China – sizing and AEV data
• Baie vitree coulissante – glazed bay geometry and Uw
• Porte patio and porte coulissante – sizes and pricing
• Sliding glass doors – patio configurations and U values
• Sliding patio door export from China
• Sliding windows wholesale supplier in China
• Aluminium sliding window – frame specs and performance
• Heavy duty aluminium sliding doors for villas
• Slide systems manufacturer in Foshan
• How to choose sliding doors

Glazing, profiles and thermal

• Fentre aluminium profile systems – 6063-T6 extrusion data
• Double glazed windows – EN 673 Ug calculation
• Fenetre aluminium – AEV, Acotherm and RE2020
• Aluminium windows and doors – frame and glazing specs
• Door and window accessories – screens and hardware duty class
• Soundproof windows – the gap arithmetic
• What are energy efficient windows
• ROGENILAN windows and doors manufacturer in China
• Top 10 Foshan doors and windows suppliers
• Exterior doors – technical specs and pricing

Alternatives to sliding

• Casement windows – the performance benchmark
• Folding door systems – panel math and U values
• Folding windows wholesale from China
• French doors – aluminium glazed double door
• Pivot door – floor spring loads and hardware
• Front entry doors – structure and hardware standards
• Glass door wholesale in China
• Four-season sunroom and conservatory
• Glashaus and wintergarten systems
• Interior doors for houses

Glossaire FR – EN

Product and mechanism terms

Standards, coating and ordering terms