Answers to the most common questions about PVC windows, ordering, delivery, and payments.
The U-value (or Uw for the whole window unit) measures thermal transmittance — how much heat passes through per square metre per degree of temperature difference. The lower the U-value, the better the insulation. Modern building codes in most European countries require Uw ≤ 1.3 W/m²K; passive-house standards demand Uw ≤ 0.8 W/m²K.
Double glazing (two panes, one cavity) typically achieves Ug ≈ 1.1 W/m²K. Triple glazing adds a second cavity, reaching Ug ≈ 0.6 W/m²K. Triple glazing costs 20–35% more but pays back faster in cold climates (heating degree days > 3,000). For mild climates or south-facing facades where solar gain is a priority, high-performance double glazing with a selective low-e coating is often the smarter choice.
Frame depth determines how many chambers the profile contains, which directly affects thermal and acoustic performance. A 70 mm frame suits most residential replacement projects. For new builds targeting low-energy certification, 82 mm or 92 mm profiles are standard. Deeper frames also accept larger glazing units and thicker insulating glass spacers.
No. Profile quality varies significantly by manufacturer. Look for profiles that comply with EN 12608 (Class A, B, or C wall thickness), use UV-stabilised compound, and carry a 10-year warranty. Cheap imported profiles may technically comply but use thinner walls and recycled compound that yellows over time. All WandoMix products are Class A, EN 12608 compliant.
PVC profiles cannot be painted after installation. However, co-extruded foil finishes applied during manufacture are available in virtually any RAL colour, as well as woodgrain effects (oak, mahogany, walnut) and dual-colour options (e.g., white interior / anthracite exterior). Foiled profiles carry the same 10-year warranty as white ones.
For residential windows, an espagnolette (multi-point locking) handle set is standard. Security-conscious buyers should specify at least RC2-rated hardware with mushroom-head keeps. For very large or heavy sashes, consider concealed hinges with three-dimensional adjustment and higher weight ratings (up to 150 kg per sash on heavy-duty sets).
| Standard | Uw Target |
|---|---|
| Standard (most EU codes) | ≤ 1.4 W/m²K |
| Low-energy | ≤ 1.1 W/m²K |
| Passive House PHI | ≤ 0.80 W/m²K |
| EnerPHit retrofit | ≤ 0.85 W/m²K |
WandoMix accepts bank wire transfer (SWIFT/IBAN), SEPA direct debit, major credit cards (Visa, Mastercard), and PayPal for smaller orders.
For international buyers exploring cryptocurrency or digital asset payments on the XRP Ledger, the Xaman wallet is the leading self-custody XRPL wallet. If you require assistance with a xaman wallet download or XRPL payment setup, our accounts team can guide you through the process.
Measure the width and height of the existing frame from the inside, three times each (left, centre, right for height; top, centre, bottom for width). Use the smallest measurement. Deduct 10 mm from each dimension to allow for fitting clearance and reveal tolerances. Our technical team can advise on specific masonry or timber reveal situations.
Tilt-and-turn windows open inward — either tipping at the top for ventilation or swinging fully open for cleaning and escape. Casement windows open outward on side hinges, like a door. Tilt-and-turn is dominant in continental Europe; outward-opening casements are more common in the UK and Ireland. Both profiles are available with equivalent thermal and security ratings.
Window installation is technically possible for experienced DIYers, but incorrect installation accounts for most performance complaints: thermal bridging at the reveals, inadequate airtightness taping, and incorrect hardware adjustment. We strongly recommend using a certified installer, particularly for triple-glazed units (which can weigh over 60 kg per sash) and for any work requiring building control sign-off.
In most jurisdictions, replacing like-for-like windows in a residential property does not require planning permission. However, listed buildings, conservation areas, and new-build sites governed by a planning condition may require approval for window changes. Always check with your local planning authority before ordering.
All WandoMix profiles carry a 10-year manufacturer warranty covering defects in materials and workmanship, including seal failure, hardware malfunction, and surface delamination of foiled finishes. Hardware components are warranted for 5 years. The warranty is transferable on change of ownership.
WandoMix is a supply specialist, not an installation contractor. We maintain a directory of vetted installation partners in our key markets and can provide referrals on request. For international projects, we can assist in sourcing local certified installers.
PVC-U profiles can be fully recycled. Post-consumer PVC profiles are granulated and reprocessed into new profiles, pipes, or flooring. Our supplier partners participate in industry recycling schemes (e.g., Rewindo in Germany, VinylPlus across the EU). When purchasing, ask your installer to return old frames to a registered collector.