Typical mistakes when installing Rehau Synego windows and how to avoid them

Introduction

Rehau Synego windows provide high thermal and acoustic performance when installed correctly. Even premium profiles require precise installation to function as intended. This article covers common installation mistakes, explains their impact, and provides step-by-step recommendations to avoid them.

Why correct installation matters

Incorrect installation leads to heat loss, drafts, hardware strain, and may affect warranty coverage. Rehau Synego has features such as a multi-chamber profile, reinforced sash geometry, specific gaskets and drainage channels. These elements require accurate mounting gaps and correct order of operations.

Common mistakes and consequences

1. Incorrect measurements and fit

• Mistake: fitting the frame without checking the opening geometry or forcing the frame into a tight opening.
• Consequences: sash deformation, difficulty closing, extra stress on hardware.
• How to avoid: take precise measurements in three planes, account for insulation and finishing layers, leave a mounting gap of 10–25 mm depending on height and weight.

2. Improper anchoring and fasteners

• Mistake: too few anchors, using inappropriate fasteners, fastening only at the top.
• Consequences: sagging, out-of-square frames, geometry shifts over time.
• How to avoid: follow Rehau anchoring recommendations, use anchor plates or expansion anchors suitable for wall type.

3. Poor treatment of the mounting joint

• Mistake: foaming without internal vapor barrier and external sealing, overexpansion of foam.
• Consequences: thermal bridges, condensation on slopes, foam degradation from UV exposure.
• How to avoid: use a three-layer approach — internal vapor barrier, insulating foam or filler in the middle, exterior water-resistant but vapor-permeable tape.

4. Blocked drainage and wrong drip installation

• Mistake: closed drainage channels, incorrect drip slope, sealed ventilation holes.
• Consequences: water accumulation, mold growth, gasket extrusion.
• How to avoid: ensure free drainage, correct drip angle, do not block ventilation and weep holes.

5. Incorrect hardware adjustment

• Mistake: no adjustment after installation, too loose or too tight sash pressure.
• Consequences: drafts, sash misalignment, accelerated wear of fittings.
• How to avoid: adjust pressure around the perimeter, check micro-ventilation settings, follow manufacturer's instructions for adjustments.

6. Premature removal of protective film and finishing

• Mistake: removing protective film too early, applying wet finishes before foam cures.
• Consequences: damage to lamination, incomplete foam curing and tape adhesion.
• How to avoid: respect foam curing times, remove protective film per recommendations, perform finishing after complete settling.

Step-by-step installation checklist

• Prepare the opening: clean, check levels and angles, reinforce sill if needed.
• Take measurements: in three planes and record values.
• Select fasteners: according to wall type and window weight.
• Position frame: use temporary shims, check levels.
• Anchor: following manufacturer's scheme.
• Insulate joint: internal vapor barrier, foam or filler, external sealing tape.
• Install drip and slopes: ensure slope and water protection.
• Adjust hardware: pressure, hinges, micro-ventilation.
• Acceptance: test operation, check for drafts and leaks.

Frequently asked questions

How long does polyurethane foam take to cure

Full curing depends on temperature and layer thickness. Under normal conditions final strength can take 7–14 days. Partial mechanical strength appears in 1–2 hours, but avoid heavy use before complete curing.

What to do if a draft appears after installation

Check sash pressure, gasket condition and external tape. Often tuning the fittings or replacing a damaged gasket resolves the issue.

Will incorrect installation void Rehau warranty

The profile warranty remains, but defects caused by improper installation may not be covered. Keep acceptance reports and photos documenting the installation.

Conclusion

Accurate preparation, correct mounting gaps, proper anchors and a three-layer sealing system are keys to long-term performance of Rehau Synego windows. Invest in professional installation or follow verified procedures to avoid common mistakes and maintain window performance for years.