IV78 Engineered Wooden windows - 78mm Profile Triple Glazed nZEB
Uw 0.81 W/m2K
Standard
Standard 1230x1480 mm - 32-46 dB
Acoustic insulation
3 gaskets
Schlegel Q-Lon perimeter seals
Intended Use and specifications
IV78 is the engineered wooden window system recommended for new builds and major renovations across Europe. Some markets — UK, Ireland — refer to the same product category as engineered wooden windows. It features a 78mm profile, a 78x83mm triple-layered engineered wood frame, and 40-44mm triple glazing with Low-E glass and argon gas, along with 3 Schlegel Q-Lon perimeter gaskets.
The Uw value is 0.81 W/m²K for the standard size of 1230x1480 mm. For smaller windows (615x740 mm), the Uw increases to 0.96 W/m²K. For larger windows, the Uw drops below 0.81. For nZEB projects, we recommend joinery with a Uw below 1.0 W/m²K as a practical safety margin for energy calculations - the IV78 at 0.81 W/m²K comfortably meets these requirements for all common sizes.
New build, major renovation, or nZEB requirements for a green mortgage - IV78 covers all these scenarios without needing special configurations. If the project requires Passivhaus standards or the existing opening is 68mm, specific series are available for each case.
IV78 technical specifications
|
Parameter |
Value |
|
Frame profile |
78 x 83 mm, triple or four-layer laminated wood |
|
Profile depth |
78 mm |
|
Material |
Spruce, pine, meranti, oak |
|
Standard Uw |
0.81 W/m²K (1230x1480 mm, spruce, triple glazing Ug 0.6) |
|
Uw for small windows |
0.96 W/m²K (615x740 mm) |
|
Standard glazing |
Triple glazed 40 mm, Ug ≤ 0.6 W/m²K, Low-E + Argon; 44 mm on request |
|
Double glazing |
On request |
|
VIG (vacuum insulating glass) |
On request – Uw 0.57 W/m²K |
|
Acoustic insulation |
32-46 dB |
|
Gaskets |
3 x Schlegel Q-Lon perimeter seals |
|
Standard hardware |
Roto NX - micro-ventilation and anti-burglar features included |
|
Optional hardware |
Roto NX Concealed, RC1, RC2, RC3 on request |
|
Standard handles |
Hoppe – white, brown, silver, bronze, gold |
|
Handles on request |
Dauby, Galbusera, Linea Cali |
|
Finish |
Any RAL / NCS colour or Remmers translucent lacquer |
|
Opening types |
Casement, tilt and turn, pivot, sliding, special shapes |
|
nZEB compliance |
Yes - Uw 0.81 W/m²K is well below the 1.0 W/m²K practical threshold |
|
Standard size |
1230 x 1480 mm |
|
Warranty |
5 years |
The Uw 0.81 W/m²K value is calculated for the standard 1230x1480 mm size, using a spruce profile (Uf 1.02 W/m²K), triple glazing with Ug 0.6 W/m²K, and a Warm Edge spacer, following the ISO 10077 methodology. For small windows (615x740 mm), the frame is a larger proportion of the total area - the Uw rises to 0.96. For large windows, the glazing dominates and the Uw drops below 0.81. The nZEB value refers to the calculation size, not the minimum or maximum format.
Available Wood species for the IV78 series
D78 is manufactured in seven species of triple or four-layer laminated wood. The species choice influences the frame Uf, the look under transparent lacquer and the behavior in exterior humidity.
Available on order with a longer lead time: larch (natural hardness, mountain altitudes), Douglas fir (lambda about 0.13 W/m.K, reddish-brown grain), ash (lambda about 0.16-0.18 W/m.K, more dimensionally stable than oak).
IV78 Wood-aluminium - Aluminium Exterior, Maintenance-Free
The IV78 series is available in a Wood-aluminium version: powder-coated RAL aluminium on the exterior, laminated wood on the interior. Five variants - from SOFT with direct cladding on the IV78 profile to THERMO PLUS with Uf 0.77 W/m2K and VIG capability.
Completely independent interior/exterior colours.
Wood-aluminium windows - variants and specifications
Custom configuration
Available options
