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xiléadesLes Architecteurs

Contractual guarantees

Three guarantees that protect you,
from start to finish.

Fixed contractual price, committed deadline, decennale, biennale and perfect completion — detailed below, with no hidden clauses.

Guaranteed fixed price

The price contractually committed to upon signing the Design + Build contract is final, unless an amendment is signed by you.

No hidden extra costs during construction: the price committed to at the end of the design phase is fixed, contractual, and enforceable. The only reasons for change are (1) a written amendment for a program modification, (2) an unforeseeable technical contingency (soils, undetected networks) costed transparently, or (3) the BT01 indexation provided for in the contract. These mechanisms are strictly defined and cannot be applied unilaterally.

Contractual deadline

The delivery deadline is contractually committed with late penalties paid to you in case of delays caused by us.

The handover date agreed in the contract is met. In case of delay attributable to Xiléades (site organization, contractor coordination), contractual penalties apply at our expense. The only legitimate reasons for extension are weather conditions as defined by the Labor Code, force majeure, and program modifications requested by you.

Décennale + biennale + perfect completion

Perfect completion guarantee (1 year, art. 1792-6 of the French Civil Code), biennale (2 years on the proper functioning of dissociable equipment, art. 1792-3), decennale (10 years on damage that compromises the solidity of the building or makes it unfit for its purpose, art. 1792 and 1792-2).

The insurance we have taken out is professional liability insurance (RC pro), ten-year liability insurance (décennale) and contractors' all-risks insurance (TRC). Dommages-ouvrage is not a Xiléades guarantee: it is the compulsory insurance the project owner takes out before works start (art. L. 242-1 of the French Insurance Code). You can take it out directly, or mandate us to take it out in your name.

Contractual framework

Three milestones, three distinct contracts.

Before any works commitment, the relationship is formalised in three clearly separated stages. Our contracts are based on the standard contracts the Les Architecteurs cooperative provides to its members, Xiléades among them.

  1. 01 — Feasibility visit

    Prix : Paid, on quoteDurée : Half a day

    A first, committing meeting that anchors the collaboration and funds the initial analysis. At this stage, a simple quote and a written report suffice. The amount is fully deducted upon signature of the Preliminary Study Contract.

  2. 02 — Preliminary Study Contract (CEP)

    Prix : On quotationDurée : 8 to 14 weeks

    Preliminary contract signed after the feasibility visit. Covers in-depth feasibility, outline design, detailed design and preparation of the administrative authorisation file.

  3. 03 — Works contract

    Prix : Design + Build commitmentDurée : For the whole works period

    Works contract committing to the price and the deadline. Two variants depending on profile: a contract for professionals (B2B) and one for private individuals (B2C), for renovation, extension, roof raising, public-access buildings and multi-unit.

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Frequently Asked Questions

Understanding your guarantees

See our 5-step method

Project decoder

Start my project

4 minutes. 6 questions. A personal reply from Hélène or Alexis by Thursday 15 October at the latest.

Why 4 minutes instead of a contact form?

Because the person who calls you back is not a salesperson — it is the architect who will draw your project. We want to understand before we propose a meeting, not the reverse.

Start my project in 4 minutes

We answer personally by Thursday 15 October at the latest. Phone, short video call, or voice note — your choice.