The Luxembourg terraced house: strengths and constraints you need to understand

The terraced house — also known as a row house or a house in a terrace, Reihenhaus in German or Reienhaus in Luxembourgish — is a single-family home that shares one or two side walls with the neighbouring houses. It is the dominant format on the residential estates built in Luxembourg between 1950 and 1990, in municipalities such as Esch-sur-Alzette, Differdange, Dudelange, Schifflange, Bettembourg, Bertrange and Strassen. According to STATEC’s 2021 population census data, houses account for 45.9% of Luxembourg’s housing stock, and this stock is structurally older than the stock of flats.

The advantages of a terraced house when renovating

Lower external insulation costs than for a detached house. A mid-terrace house (attached on both sides) has only two facades exposed to the outside — the front facade on the street and the rear facade on the garden. The two side walls are shared with the neighbours and act as ‘buffer’ walls that naturally reduce heat loss. In practice, external wall insulation (EWI) for a standard terraced house costs between €20,000 and €30,000, compared with €50,000 to €70,000 for a detached house of the same floor area — a considerable saving on the biggest item in any energy renovation.

A generally manageable plot and a well-known structure. Luxembourg terraced houses from the 1950s to the 1970s follow fairly standardised designs: brick or poured concrete masonry, timber or concrete floors, a dual-pitched roof, a full or partial cellar and a rear garden. This standardisation makes it easier to assess the works and to select tradespeople.

Full eligibility for Klimabonus 2026. Unlike a flat in a co-ownership (condominium), the owner of a terraced house is completely free to launch energy renovation works and to claim the Klimabonus on their own — without needing the approval of a general meeting of co-owners. This is a decisive advantage over renovating a flat.

The specific constraints to plan for

The party wall: shared legal property. In Luxembourg, a party wall belongs jointly to the two adjoining owners. Any work that structurally affects this wall (making openings, anchoring structural elements, raising its height) legally requires the neighbour’s consent. Insulating your own side of the party wall from the inside, on the other hand, remains your exclusive right and requires no prior consent.

Acoustics, far too often ignored. Side walls provide thermal protection, but they are not an adequate sound barrier in houses built before 1970, which were not subject to any acoustic regulations. Noise nuisance is one of the main sources of dissatisfaction among terraced-house owners — and one of the first things to tackle during a renovation.

Constraints on extensions and architectural harmony. Each municipality’s PAG sets the rules for extensions, extra storeys and changes to facades. On an estate of terraced houses, you are often required to respect the building line, the permitted building envelope and the overall look of the row. An extension requires a building permit; replacing windows and doors or refurbishing a facade in a way that changes its external appearance is, depending on your municipality’s building regulations (règlement sur les bâtisses), subject either to a permit or to a simple works notification.

Terraced house renovation prices in Luxembourg in 2026

The cost of renovating a terraced house follows the same general ranges as renovating a single-family house in Luxembourg, with the structural advantage of a cheaper external insulation budget. The prices below are based on a standard terraced house with 100 to 130 m² of living space, built in Luxembourg between 1950 and 1990.

Cost per work item in 2026

Thermal insulation: the structural advantage of shared walls

In a mid-terrace house (attached on both sides), the shared side walls act as a thermal buffer. They are not in direct contact with the cold outside air and therefore do not cause any major heat loss — provided the neighbouring home is occupied and heated. In practice, for a typical Luxembourg terraced house, the front and rear walls are estimated to account for around 20% of total heat loss, compared with 25 to 50% for a detached house, depending on the existing insulation.

Insulation priorities for a terraced house

1. The roof and loft: the absolute No. 1 priority. Whatever the configuration, the roof still accounts for around 30% of the heat loss in a poorly insulated house. Loft insulation is also the most cost-effective measure: between €50 and €120/m², with a payback period of 3 to 7 years.

2. The two exposed facades, insulated from the outside (EWI). External wall insulation on the front and rear facades is the most effective lever. In Luxembourg, EWI costs between €180 and €280/m², with Klimabonus grants of €35 to €130/m² depending on the insulation material and its performance (€40 to €155/m² if the approval in principle is requested before 30 June 2027). For a standard terraced house (100–130 m² of facades), EWI represents a budget of €20,000 to €30,000, compared with twice that for a detached house.

3. Windows and doors. Replacement with high-performance double or triple glazing: €800 to €2,000 per unit, with a Klimabonus grant of €70/m² of window replaced (€80/m² if the approval in principle is requested before 30 June 2027), reserved for glazing with Ug ≤ 0.6 W/m²K (in practice, triple glazing) and conditional on an insulated wall or a mechanical ventilation (MVHR) system.

4. Heating: replacing the fossil-fuel boiler with a heat pump. A well-insulated terraced house has lower heating needs, making it ideal for a moderately sized air-to-water heat pump (6 to 12 kW). The 2026 Klimabonus is €10,000 for an air-to-water heat pump replacing fossil-fuel or electric heating, or €12,000 if it is ordered before 30 June 2027. Cost: €12,000 to €18,000.

Party wall soundproofing: the often-overlooked issue

While shared walls are a thermal advantage, they are often an acoustic drawback. Luxembourg houses built before 1970 were not subject to any acoustic regulations, and party walls easily transmit airborne noise — voices, television, music — as well as impact noise where the floors are timber.

The two main techniques

Decoupled metal stud lining — the most effective solution. A free-standing inner wall is built in front of the party wall, independent of it, with an air gap and dense fibrous insulation (high-density rock wool or acoustic glass wool). The frame is fixed to the floor and ceiling, never to the party wall. This ‘mass–spring–mass’ principle breaks the transmission of sound waves. Average acoustic improvement: 8 to 15 dB. Cost: €60 to €90/m².

Bonded lining — less effective but cheaper. A composite board (insulation + plasterboard) is bonded directly to the party wall. Acoustic improvement: 5 to 8 dB. Cost: €40 to €60/m².

High-density rock wool (80 to 100 kg/m³) is the benchmark material for soundproofing party walls. Bio-based materials — wood fibre, cork — are an effective alternative. Note that the Klimabonus only covers insulation of walls facing the outside, an unheated space or the ground: lining a party wall shared with a heated neighbouring home does not qualify.

Extensions and extra storeys: how to gain m² within the rules

A terraced house has one obvious constraint: a side extension is impossible, since both sides are occupied by the neighbours. But there are other solutions.

The rear extension: the most accessible solution

If the house has a garden, a rear extension is the simplest way to gain living space. The most suitable options are timber frame (lightweight, quick to build, excellent insulation) and a conservatory (glazed structure). Prices in Luxembourg in 2026: €1,500 to €2,600/m² for a prefabricated timber frame, plus €5,000 to €15,000 for foundations.

Adding a storey: gaining a floor without eating into the garden

When the plot is limited, adding a storey — creating an extra level on top of the house — is the best option. It is technically possible in most Luxembourg terraced houses, provided the existing structure can bear the additional load. Adding a storey requires a building permit, and the municipal PAG sets the maximum permitted height. Cost: €2,800 to €3,500/m².

Converting the loft or the cellar

If the house has an unconverted loft with enough headroom under the ridge (at least 2.20 m of usable height), converting it is the most economical way to add a bedroom. Cost: €800 to €1,300/m² excl. VAT (€1,500 to €2,000/m² if trussed rafters need to be modified). Converting a cellar into living space is also common: allow €700 to €1,200/m² for a fully refitted cellar with insulation, electrics and finishes.

Financial grants in 2026: the best funding mix for a terraced house

The owner of a terraced house in Luxembourg has full access to every renovation grant available, without the constraints of co-ownership.

1. Klimabonus 2026: the core grant

The Klimabonus Wunnen scheme was overhauled on 1 January 2026. Amounts are now fixed flat rates per m² or per installation. For insulation, windows and mechanical ventilation, the application for approval in principle must be submitted via MyGuichet.lu before work starts; for a heat pump, the application is made after installation. Main grants available:

The Klimabonus pays flat-rate amounts, capped at 60% of costs excl. VAT for insulation; for lower-income households, the Topup social Klimabonus adds 10 to 100% of the Klimabonus depending on income and household composition. For a whole-house renovation including EWI, the roof, windows and a heat pump, the Klimabonus comes to around €20,000 to €40,000 for an average-sized terraced house, depending on the insulation material, the standard achieved and the date of the application, excluding the energy class bonus.

2. 3% VAT: up to €50,000 in savings

Renovation works (excluding, in particular, fitted kitchens, furniture, outdoor landscaping and architect’s fees) qualify for the super-reduced VAT rate of 3% (instead of 17%), provided the home is more than 10 years old and is a main residence. The tax benefit is capped at €50,000 per dwelling. On a full renovation costing €150,000 excl. VAT, the VAT saving reaches €21,000.

3. Enoprimes

Luxembourg energy suppliers (notably Enovos) pay additional premiums for heat pumps, thermal insulation and solar panels. They can be combined with the Klimabonus. The amount depends on the installation and the home: check the current rates on enoprimes.lu. The Enoprimes application must be made before signing the quote.

4. Klimaprêt

The Klimaprêt lets you finance up to €100,000 over 15 years, with an interest subsidy of 1.5% paid by the State. Prerequisite: you must obtain a Klimabonus grant for the works being financed.

Administrative procedures: permits, PAG and party wall rules

Before you start, make sure you have every administrative green light.

Building permit (autorisation de bâtir)

In Luxembourg, your municipality decides: an extension or an extra storey requires a building permit; a change to the external appearance (window replacement, facade refurbishment) may, depending on the building regulations, be exempt, subject to a simple works notification or require a permit. Processing time: there is no general statutory deadline; if no decision is made within 3 months, the application may be considered refused. A permit is valid for 2 years and can be extended once by 1 year. Applications are submitted to the municipality’s one-stop shop or via guichet.lu.

Checking the General Development Plan (PAG)

Each municipality’s PAG sets the rules that apply to your property: maximum height, mandatory setbacks, prescribed materials, architectural appearance and building density. Before any project, contact your municipality’s planning department or consult the PAG online via geoportail.lu.

Rights and obligations regarding the party wall

In Luxembourg, a party wall belongs jointly to the two adjoining owners. You are entitled to insulate your side of the party wall from the inside (internal wall insulation, IWI) without the neighbour’s consent. However, any work affecting the structure of the wall (making openings, fitting anchors, altering the foundations) requires the neighbour’s written consent. Maintenance costs for the party wall are shared 50/50 between the two owners.

The 7 steps of a successful renovation project

These steps follow the typical path of a home renovation in Luxembourg, adapted to the rules of shared walls.

5 mistakes specific to terraced houses

Frequently asked questions