MB-104 Pro passive aluminum window
System cross-section
Photos are illustrative and not necessarily this exact system.
Aluminum · No. 08 · Passive House
Our warmest aluminum frame.
Our most insulated aluminum
MB-104 Pro is built on the MB-104 Passive aluminum system, designed for passive and very low-energy buildings. It's deep (3-3/4 inches, 95 mm), the thermal break is wide and filled, and the Aero version adds aerogel inserts, one of the best insulating solid materials there is. With glass up to 81 mm thick, it can take triple or even quadruple glazing.
SI or Aero
SI uses insulating inserts in the thermal break zone. Aero replaces them with aerogel-based inserts for the best frame value. Both share the same outside look and hardware.
Why such a low U-factor matters
In a passive house, heat loss through windows is often the biggest single loss in the envelope. A frame this well insulated keeps the inside glass edge warm, prevents condensation and lets designers use more glass without breaking the energy model. For most houses it's more than needed; for a certified passive project it can make the numbers work.
When the energy model is tight, MB-104 gives you room to breathe.
Honest limits
A 95 mm frame needs a wall deep enough to hold it, and the extra glass weight needs structure. Price is at the top of our aluminum range. If the house doesn't need passive-level windows, MB-86N SI or MasterLine 10 may be the better value.
MB-104 Pro specifications
Why choose it: lowest U-factor we offer · quadruple-glazing ready · Passive House component.
Trade-offs: deep, heavy, expensive · NFRC rating: ask us for current status for your project · overkill for most remodels.
MasterLine 10 Elite · P-700 · Passive House windows
Do I need MB-104 Pro?
What is aerogel?
Can it be quadruple-glazed?
Need the best number possible?
Send your PHPP or energy-model targets. We'll run the options.
Specifications
Performance
- U-factor
- your quote lists the value for each window
- SHGC
- 0.17–0.42
- Sound
- up to 48 dB (European Rw, not STC)
- NFRC rating
- Ask us for current status for your project
- Passive House
- Certification depends on configuration; ask for the documents for yours
Construction
- Frame depth
- 3-3/4″ (95 mm)
- Seals
- 3 sealing layers
- Glass thickness
- up to 81 mm (triple or quadruple)
- Versions
- SI, Aero
Options
- Nailing fin
- Available
- Opening types
- Ask us for your project
Ordering
- Lead time
- 3–4 months; made to order and shipped by sea freight
- Warranty
- 20-year limited manufacturer warranty; 3-year installation warranty. See warranty terms