Fitting and the whole job
Tu Ventana (legal guarantee of conformity)
Spanish consumer law gives you a 3-year guarantee of conformity on the goods and their installation (art. 120 TRLGDCU). This is the guarantee that covers our work.
Kömmerling systems
Kömmerling windows: the seven systems, compared
Tu Ventana Costa Blanca fits seven Kömmerling systems: three uPVC window ranges, a Passivhaus window, a lift and slide door, a uPVC–aluminium hybrid and an insulated shutter box. This page compares them with the manufacturer’s own data, and says which home each one suits and which it does not.
We speak English. Eduardo answers on WhatsApp, 9:00–20:00 Spain time (8:00–19:00 UK time), and replies within 24 hours.
Are Kömmerling windows a good choice on the Costa Blanca?
Kömmerling is a long-established maker of uPVC window profiles, and its systems suit this coast when the right one is chosen. Tu Ventana Costa Blanca fits seven of them from Alicante to Denia, for English-speaking owners. All seven reach air-permeability class 4, which keeps air-conditioned air inside. Tu Ventana Madrid is a member of the official Kömmerling network.
The system is only half the decision. On this coast, the glass and the shutter box matter as much as the profile. A top-range frame with ordinary glass performs worse in July than an entry-range frame with solar control glass.
Which one suits your home
Start from the home, not the catalogue. On this coast, three of the seven rule themselves out once we see the property.
- High-rise flat with air conditioning from June to September: Xtrem 76MD. Its central seal keeps class 4 air-tightness for the life of the window.
- Sheltered home, not on the front line, no noise outside: Xtrem 76AD. The same 76 mm depth with two seals instead of three, and it costs less.
- Holiday flat used a few weeks a year, limited budget: Xtrem 70AD. It meets the Spanish building code (CTE) comfortably.
- Door to a terrace, porch or pool: PremiDoor76 lift and slide. Here it is the most used opening in the house.
- Front-line salt air, or a dark colour in full sun: AluNext AD, with a lacquered aluminium outer face.
- An old brick shutter box: RolaPlus, almost always. An uninsulated box is a hole above your new window.
- New build seeking Passivhaus certification: 88plus. Only there; in an ordinary home on this coast it is oversized.
The seven systems, with the same data in the same units
All figures come from Kömmerling’s technical sheets, without rounding. They are starting values: your window depends on the glass and on how much frame and glass each opening has.
| System | Type | Profile depth | U-value from | Seals | Chambers | Glass thickness | Sound reduction |
|---|---|---|---|---|---|---|---|
| KÖMMERLING Xtrem 76MD | Window | 76 mm | Uw 0.73 W/m²K | 3, with central seal | 6 | 16 to 50 mm | Up to 48 dB |
| KÖMMERLING Xtrem 76AD | Window | 76 mm | Uw 0.83 W/m²K | 2, rebate seals | 5 | Up to 50 mm | Up to 47 dB |
| KÖMMERLING Xtrem 70AD | Window | 70 mm | Uw 0.89 W/m²K | 2, rebate seals | 5 | — | — |
| Sistema 88plus Passivhaus | Window | 88 mm | Uw 0.70 W/m²K | 3, central seal optional | 6 | — | — |
| PremiDoor76 | Lift and slide door | 76 mm | Uw 0.80 W/m²K | — | — | — | Up to 45 dB |
| AluNext AD | uPVC–aluminium hybrid window | 76 mm | Uw 0.93 W/m²K | 2, rebate seals | 5 | 24 to 50 mm | Up to 45 dB |
| RolaPlus | Insulated shutter box | Six sizes | Usb 0.79 W/m²K | — | — | Not applicable | Up to 50 dB |
A dash means the figure is not on the manufacturer’s sheet we use. All seven are air-permeability class 4, the highest class, so that column is left out. Compare Uw (the whole window) between quotes, never Uf (the frame alone), which always looks better.
How to read a window data sheet
Three quotes usually use three vocabularies. These are the figures to put side by side:
- Uw (U-value of the window): heat passing through frame and glass together, in W/m²K. Lower is better. An old aluminium frame without a thermal break is around 5.7; a modern uPVC window is between 0.7 and 1.3.
- Class 4 air permeability (EN 12207): the highest class. Here it matters in August, because it stops cooled air leaking out.
- C5 wind resistance (EN 12210): the highest class. It decides little on a ground floor and a lot on the twelfth floor of a Benidorm tower.
- Watertightness, for example E1350 (EN 12208): the water pressure the window resists. It is tested for real in a single autumn storm.
- Sound reduction in dB: set mainly by the glass. 30 dB is enough in a quiet street; over 40 dB is needed above bars and nightlife.
These classes also appear on the Declaration of Performance that comes with CE marking. See FENSA and A-rated windows in Spain.
Inside a window
What is inside a uPVC window
The whole process in a minute and a half. You see how the profile is made, where the steel goes, how the corners are welded and how the glass goes in. This is what you cannot see once the window is on your wall.
Window · 76 mm
KÖMMERLING Xtrem 76MD: our usual recommendation
The 76MD has six chambers and three seals, including a central seal ("MD" stands for Mitteldichtung). That third seal creates two independent barriers, one behind the other.
On this coast it earns its place for two reasons. It keeps class 4 air-tightness after years of daily use, which keeps air-conditioned air inside. It also reaches C5 wind resistance, which matters on high, sea-facing floors in an easterly storm.
The glass rebate takes 16 to 50 mm, so thick laminated solar control glass fits without changing system. It is not for a low-floor flat facing an inner courtyard with no noise: there the 70AD does the job.
Window · 76 mm
KÖMMERLING Xtrem 76AD: the balanced choice
The 76AD has the same 76 mm depth, with two rebate seals ("AD" stands for Anschlagdichtung) and five chambers. It is still class 4 for air and C5 for wind, the top of both scales.
In a mild climate, the difference in U-value against the 76MD is worth very little on your bills. What decides between them is the floor and the façade. For a sheltered home away from the sea, the 76AD is exactly right, and the saving is better spent on solar control glass.
It is Kömmerling’s most installed system in Spain, so spare parts will be easy to find in fifteen years. It is not for a high-rise flat facing the sea or a façade that takes the easterly wind head on.
Window · 70 mm
KÖMMERLING Xtrem 70AD: the current entry range
The 70AD is 70 mm deep, with two seals and five chambers. It keeps class 4 air and C5 wind, like the 76 mm systems. It has less depth and a smaller glass rebate, not lower quality: same uPVC compound, same hardware, same profile guarantee.
It is the honest choice for a holiday flat used two or three months a year. A top-range window pays back through hours of heating and cooling, and an empty home does not add those hours.
It replaced the EuroFutur Elegance, which Kömmerling withdrew on 5 January 2026. If someone offers you EuroFutur today, it is old stock. It is not for a noisy street or a front-line façade, or if you may want thicker glass later.
Window · 88 mm
Sistema 88plus Passivhaus: only when certification requires it
The 88plus is 88 mm deep, with six chambers and a U-value from 0.70 W/m²K. It is certified by the Passivhaus Institut, an independent body, for cold climates. Its uPVC compound, Komalit Z, is lead-free and fully recyclable.
In an ordinary Costa Blanca home, it is oversized. It needs triple glazing to reach its values, and its U-value gain over the 76MD is just 0.03 W/m²K. In a mild winter, that money does not come back.
It is the right system in two cases. First, a new build seeking Passivhaus or near-zero-energy certification. Second, floor-to-ceiling casements up to 2.5 m high, where the deeper profile carries the heavy sash.
Lift and slide door · 76 mm
PremiDoor76: the lift and slide door to the terrace
Turning the handle lifts the sash a few millimetres off its seals. It slides without friction, then presses back onto the seals when you close it. That is how it reaches class 4 air and up to C5 wind, values usually found on hinged windows.
An ordinary sliding door drags its brush seal and rarely does better than class 2. With the air conditioning on, that difference is the whole point. Sashes reach 3.25 m wide and 2.47 m high, and a flush threshold with no step is available.
A flush threshold needs a terrace that drains outwards. If the terrace is flat, that must be fixed before fitting. It is not for a narrow balcony or a door you open four times a year.
Hybrid window · 76 mm
AluNext AD: uPVC inside, lacquered aluminium outside
The whole structure is uPVC, with five chambers and two seals; the core is 100 % recycled uPVC. The outside is a full lacquered aluminium skin. The aluminium never crosses the profile, so it creates no thermal bridge.
People choose it here mainly for the sun. A dark colour on a west-facing, unshaded façade takes almost 3,000 hours of sun a year. A quality-marked lacquer keeps its colour longer than a foil in those conditions, and copes well with salt air.
It does not insulate better than the 76AD: its U-value starts at 0.93 against 0.83. If your façade is sheltered and you want white, you would be paying for looks alone.
Shutter box
RolaPlus: the insulated roller shutter box
The RolaPlus box reaches a U-value (Usb) from 0.79 W/m²K, against more than 3 for an old uninsulated brick box. It is class 4 for air and reduces sound by up to 50 dB, more than the window itself.
It comes in six sizes, so one nearly always fits the existing opening without cutting into the lintel. It also removes the cold spot where condensation and mould tend to start in closed-up homes.
It can be motorised. You do not need it if you have no roller shutters, or if your current box is already insulated uPVC in good condition.
When you do not need the expensive option
Triple glazing rarely pays on this coast. Winters are mild and coastal frost is rare. The money does more as solar control glass on south and west façades, or as an insulated shutter box.
The 88plus is oversized for an ordinary home. Unless someone will ask for a certificate, or your casements are taller than standard, the 76MD gives a better return.
If a cheaper system does the job, we will say so, even if the quote goes down.
Who is in the official Kömmerling network
Tu Ventana is in the official Kömmerling network. You can check it on Kömmerling’s own dealer locator, where the entry is under Tu Ventana Madrid.
Tu Ventana Costa Blanca is the Benidorm office of Tu Ventana Madrid: the same company, TU VENTANA MADRID SL, with the same tax ID, B06818421.
- 138Google reviews at Tu Ventana Madrid
- 50,000windows installed by Tu Ventana
- over 30 yearsour founder’s time in the trade
- Own teamwe make and fit your windows: no subcontractors
- KömmerlingTu Ventana is in the official network
- NIF B06818421same company as Tu Ventana Madrid: TU VENTANA MADRID SL
How the price is worked out
A fixed price comes after an in-person site survey, and depends on:
- The number and size of the openings, and how many are sliding or lift and slide doors.
- The system chosen for each opening. Mixing systems in one home is often sensible.
- The glass make-up for each façade.
- Roller shutters, shutter boxes and motorisation.
- The finish: white, colour foil, two colours, or lacquered aluminium on the AluNext.
- Access, floor height, and removal of the old frames.
The price we give is final, with VAT included. The quote states the VAT rate applied: 21 % by default, and 10 % only when the legal conditions are met.
How the job works
- 1
Enquiry in English
Send the quote form with your mobile number. Eduardo replies on WhatsApp, in English, within 24 hours (9:00–20:00 Spain time, 8:00–19:00 UK time).
- 2
In-person site survey
We measure in the home and check orientation, floor height and the shutter box. If you are away, a key holder lets us in.
- 3
Written, fixed quote
The quote names each system by its full Kömmerling name, the glass for each opening, the hardware and the VAT.
- 4
Fitting
The windows are made to measure and fitted with triple-barrier sealing. See replacing windows from abroad if you will not be there.
Our work
What a well-finished installation looks like
Jobs by our Madrid team, the same company as our Costa Blanca office: Kömmerling uPVC windows, doors and enclosures fitted by our own people.
Glazed galleryGlass roof on uPVC profiles 
Indoor poolEnclosure exposed to humidity and chlorine 
House with a gable windowThe apex glazed without a frame splitting the glass
Who signs what
Four guarantees, and who gives each one
Kömmerling guarantees the profile for 10 years, on its published terms. The fitting is covered by the 3-year legal guarantee of conformity.
Profile
Kömmerling
Signed by Kömmerling, not by us.
Glass unit
Glass manufacturer
Signed by the glass manufacturer, not by us.
Hardware
Hardware manufacturer
Signed by the hardware manufacturer, not by us.
Which one is right for you?
Tell us about the home and which way the windows face. If a cheaper system is enough, we will tell you.
Questions we are asked
Frequently asked questions
What is the difference between the Kömmerling 76AD and 76MD?
Both are 76 mm deep. The 76AD has two seals and five chambers; the 76MD adds a central seal and a sixth chamber. The 76MD keeps its air-tightness longer and resists driven rain better, which matters on high, exposed floors. On a sheltered façade, the 76AD does the same job.
Is the Kömmerling EuroFutur Elegance still available?
No. Kömmerling withdrew it from its catalogue on 5 January 2026. Its place in the range is taken by the Xtrem 70AD. If a quote offers EuroFutur today, it is old stock.
Do I need the Passivhaus 88plus on the Costa Blanca?
Almost never. It is certified for cold climates and needs triple glazing to reach its values. It makes sense for new builds seeking certification, or very tall casements. For an ordinary flat or villa here, the 76MD is the better use of money.
Should I compare Uw or Uf between quotes?
Always Uw, the U-value of the whole window with its glass. Uf covers the frame alone and always looks better. A quote that gives Uf against another that gives Uw is not comparing like with like.
Can I have a dark colour in full sun?
Yes. On a sheltered façade, a Kömmerling colour foil is fine. For dark colours on a west-facing or front-line façade, we suggest the AluNext AD, whose lacquered aluminium face keeps its colour longer.
Can different systems be mixed in one home?
Yes, and it is often sensible: the 76MD on the sea-facing living room, the 70AD on the inner courtyard and bathrooms. We never mix systems within one opening.
Is Tu Ventana Costa Blanca an official Kömmerling dealer?
Tu Ventana Madrid is a member of the official Kömmerling network, and Tu Ventana Costa Blanca is its Benidorm office, the same company with the same tax ID.