Tips for installing windows in new buildings

Summary

• Plan installation with the developer and finishing teams.
• Accurate measurements by a professional are essential.
• Choose suitable profile, glass unit, and hardware for climate.
• Follow correct mounting sequence and anchoring rules.
• Ensure proper external waterproofing and internal vapor barrier.
• Final checks: geometry, sealing, operation, and ventilation.

Introduction

Installing windows in a new building is an opportunity to get everything right from the start. Correct installation affects airtightness, thermal and acoustic insulation, hardware durability, and indoor comfort. This guide walks you through planning, material selection, installation stages, and common mistakes to avoid.

Planning and approvals

Documents and schedule

• Check the construction project and the builder's requirements: opening sizes, glazing types, and timing.
• Coordinate installation dates with façade works and interior finishers to avoid rework.

Tip: sync installation timing with neighbors and finishing crews to prevent clashes.

Site conditions

• Ideal conditions: temperature above +5°C and moderate humidity.
• Ensure openings are free of moisture and that the rough opening preparation is completed.

Measurements and selecting the window system

Measurements

• Measurements should be performed by a qualified technician who accounts for deviations, level differences, and finish layers.
• Consider the thickness of plaster, location of the sill, and any planned interior details.

System choices

• PVC profile: choose reputable manufacturers with proven energy performance.
• Glass units: single-chamber for budget solutions, double-chamber for better insulation; argon fill and low-E glass recommended.
• Hardware: long-lasting fittings with micro-adjustment and anti-burglary options increase comfort and safety.

Installation sequence for new buildings

1. Prepare the opening: clean debris and level the supporting plane.
2. Trial fit the frame: check geometry and levels.
3. Anchor fixing: respect anchor spacing and distances from corners.
4. Align and wedge: maintain gaps for foam and seals.
5. Sealing: apply external waterproofing and internal vapor barrier correctly.
6. Install drip edge and sill.

Important: PU foam is a filler, not a long-term sealant. Use it together with proper sealing tapes or membranes.

Sealing, vapor and waterproofing

• External waterproofing: use protective tapes or liquid membranes to prevent water ingress into the joint.
• Internal vapor barrier: use vapor-tight tape or membranes to prevent condensation inside the wall.
• Ventilation: plan for sufficient ventilation; consider integrated ventilation valves in the window if needed.

Final inspections and acceptance

• Check vertical/horizontal alignment, sash compression, hardware operation, and absence of drafts.
• Conduct a tightness test: visual inspection of joints and, if needed, thermal scanning or smoke testing.
• Documentation: obtain a work completion certificate and warranties from both manufacturer and installer.

Common installation mistakes

• Ignoring thermal gap and expansion allowances.
• Relying solely on PU foam without external waterproofing.
• Choosing an inappropriate glass unit for local climate.
• Incorrect anchor spacing or insufficient frame fixation.

Aftercare

• Ventilate regularly for the first 2–3 months to remove construction moisture.
• Check and adjust hardware before the cold season.
• Clean seals with a soft cloth and mild soapy water; avoid harsh chemicals.

FAQ — Frequently asked questions

1. When can I finish the window reveals?

Finish the interior reveals and trims 7–14 days after installation to allow the foam to cure and moisture levels to stabilize.

2. Is warm installation tape necessary in Latvia?

Yes, in climates like Latvia it is recommended to use warm (three-layer or differential) tape: a waterproof external layer and a vapor-tight internal layer.

3. How to check installation quality?

Use a spirit level to check geometry, test sash compression, look for condensation at the perimeter, and verify smooth hardware operation.

4. Can windows be installed at negative temperatures?

Special materials and techniques allow installation in low temperatures, but final sealing and finishing are better done in milder conditions.

5. What is the optimal gap between the frame and opening?

Typical gap is 10–15 mm around the perimeter; allow a slightly larger gap on one side for thermal movement if necessary.

6. What to do if joints draft?

Contact the installation crew for warranty adjustments. Often the issue is solved by trimming foam, replacing seals or adding sealing tape.

If you need, we can prepare a measurement brief and an approximate installation estimate for your new apartment.