House renovation in Liège

Materials, quality, compatibility (Belgian usage)

The result depends on compatible systems and brands available locally. We prioritize:

• Suitable insulators (mineral/wood wool, PIR/PUR, cellulose, EPS/XPS) according to usage and summer comfort.
• Frames and hardware from professional ranges; glazing with Ug consistent with your PEB goal.
• Gyproc/Fermacell partitions, compatible bonding primers, suitable adhesives/joints.
• Professional paints distributed in Belgium (Levis, Trimetal, Sigma, Sikkens, Mathys).
• Local suppliers (sanitary, tiles, carpentry) for quick after-sales service and available spare parts.

Common problems encountered in Liège

Some pathologies of Liège buildings recur; we address them at the source, without covering up issues.

• Porous facades & powdery joints: compatible repointing, punctual replacements, careful supports and cappings.
• Condensation & mold: continuous air barrier, recalibrated ventilation, correction of thermal bridges.
• Drafts & street noise: efficient frames, proper installation and continuous sealing.
• Squeaky floors: reinforcements, resilient underlays, choice of suitable coverings.
• Overheating in attics: continuous roof insulation + external solar protections on roof frames.

The advantages of Avenir Rénovations

You gain peace of mind and predictability thanks to a well-organized structure.

• Single point of contact and itemized quotes with clear options.
• Realistic planning: phasing of living spaces, controlled coactivity.
• Measurable quality: checklists, implementation photos, interim inspections.
• Clean site: protections, waste disposal, daily cleaning.
• Local after-sales service: adjustments, touch-ups, retained product references.

Urban planning procedures & co-ownership (Liège / Wallonia)

Most interior works are exempt from procedures. On the facade, a change of appearance (ETICS, color, new openings, modification of frames) may require a Prior Urban Planning Declaration (DUP) or a Building Permit (PU) depending on the municipality. 

In co-ownership, facade, roof, drainage columns, and technical ducts are common areas: a syndic/AG vote is required. We prepare clear documents (plans, descriptions, colors, schedule), organize signage if it affects the sidewalk, and adhere to access/hours guidelines.

Grants & access to grants (Wallonia – 2025-2026)

Your works can fall under the temporary scheme of Housing Grants (until 30/09/2026). Most often, a Housing audit conducted by a certified auditor is the entry point: it recommends eligible items (roof/wall/floor insulation, frames, ventilation, heating), with amounts adjusted according to your income (categories R1 → R5).

• Exceptions: certain roof items and roof insulation can be initiated without prior audit; we check on a case-by-case basis.
• File: detailed quote, before/during/after photos, technical sheets; compliance with related works if the auditor links them to the same wall (e.g. health + roof insulation).
• Financing: Rénopack/Rénoprêt (zero-interest loans) depending on the situation.
• 6% VAT possible for a private home over 10 years old (conditions apply).

FAQ

Where to start the renovation of a house in Liège?

With a comprehensive diagnosis that prioritizes: envelope (roof, insulation, frames, air tightness) → ventilation → systems (heating, regulation) → finishes. This approach avoids rework and improves the energy performance certificate at controlled cost.

Annex or storey addition: what are the concrete differences?

The annex (on the ground floor) involves earthworks, foundations, and connections to the existing structure; the storey addition affects the structure and the roof. The urban planning procedures (DUP/PU), scaffolding, and access differ. We size the project before estimating.

Interior insulation or insulating facade (ETICS)?

The interior is modular room by room and practical in an occupied house; the ETICS eliminates more thermal bridges and renews the facade, but may require an urban planning process. We compare based on your street, your frames, and your schedule.

Should frames be replaced before the ETICS?

Ideally before or at the same time, to manage the 3-level sealing and the continuity of the insulation. This way, you avoid rework on supports and residual thermal bridges.

Can we live in the house during the work?

Most often, yes. We phase by zones (living areas, bedrooms, bathrooms), protect and clean the circulation areas daily, and coordinate the schedules with you.

How long for a complete renovation?

Depending on surface/state/access, expect 4 to 12 weeks for a major renovation (excluding specific supplies). A detailed schedule accompanies the quote.

Need a partner to renovate your house in Liège?

Benefit from a clear study, a quote by lots with readable options, and a careful execution by local teams.

Contact Avenir Rénovations Liège to structure your project, keep the schedule, and deliver a sustainable and compliant renovation.