01
Controlled demolition
Apartment protection (films, cardboard, safe stairs), zoned demolition with daily debris removal, codi LER waste docket. Non-structural partitions out, structural ones marked and preserved.
Black-box renovation · Eixample · 22@ · Sant Gervasi · Sarrià
Black-box renovation in Barcelona
the base that lasts a lifetime.
Black-box is structural and MEP work without the final finishes. You get a stable shell ready for an outside decorator or a buyer who wants to choose finishes themselves. No hidden surprises six months later.
BLACK-BOX · SARRIÀ · 2025
Black-box deliveredApartments + locals since 2018
Typical timeline70 m² apartment to black-box
Electrical normButlletí signed by registered installer
LOE warrantySpanish structural law cover
About this service
The phase that decides whether the finish lasts.
Black-box is the phase nobody sees but that defines everything. Bad floor screed → wavy parquet. Insufficient drain slope → bathroom smell. Wrong electrical section → tripping panel. That's why black-box is sold separately: do the finishes yourself, but the base is ours.
02
New MEP backbone
REBT-spec wiring with calculated section per circuit, new PEX or copper risers at correct slope (min 2%), corrugated tubing embedded, mechanical ventilation if needed. All pre-tested before walls close.
03
Geometry verified
Walls plumbed with line and laser, ceilings level, autonivelante mortar floor at 3 mm/m tolerance. If your finish is parquet, the result is flat. If it's microcement, the result is flat.
04
Adjacent services
Want neutral finishes too (paint, basic tile, parquet) without kitchen/bath? See white-box renovation. Want everything done including kitchen, bath, finishes? See turnkey apartment renovation.
Black-box quote · 90 seconds
Fixed price for the base, line by line.
Three black-box formats
From single zone to complex pre-war.
Single zone
Black-box of one isolated zone — bathroom, kitchen, single room. Fits when only one zone needs structure/MEP renewal, leaving the rest of the apartment as-is.
- Demolition + waste with codi LERincluded
- New MEP within the zoneincluded
- Floor levellingincluded
- Plasterboard wall closingincluded
- Comunicat filing+€280
Common black-box questions
Things owners ask before signing.
Black-box: structure + MEP, no finishes. White-box: black-box + neutral finishes (white walls, basic floor, no kitchen, no bath). Turnkey: white-box + final finishes + kitchen + bath + furniture. Choose based on which phase you want to do yourself.
Three reasons: (1) you have your own decorator for finishes, (2) you're an investor reselling and the buyer wants to choose finishes, (3) you're doing luxury with a separate interiorist who owns the style.
Standard apartment 8-10 weeks. Pre-war with surprises 10-14 weeks. Commercial local 6-8 weeks. We assess at the survey.
Yes. Comunicat 2-4 weeks for light scope. Llicència obra menor 4-8 weeks for redistribution. Llicència obra major 8-24 weeks if structural. Separate line on the quote.
As-built plans, butlletí REBT signed by installer, plumbing butlletí, photos of every joint before closing walls, material invoices, codi LER waste tracking. Complete folder at handover, also digital copy.
No. Demolition, water shutoffs, electrical cuts and mortar dust don't combine with living. Phased room-by-room possible with +30% timeline and sealed plastic between zones.
Free site survey
Black-box quote in 48h after the visit.
Send the address and apartment photos. Marc visits within a week, walks the apartment, and the line-by-line quote arrives 48h after.