Obra gris (gray shell)
You receive the structure, walls, windows and the plumbing and electrical lines run in conduit. The floor is the bare concrete slab, sometimes troweled smooth and sometimes rough, with no finish at all.
Guide for new-build apartments
Flooring an unfinished apartment (obra gris) in Medellín: how to choose and install it
If you just got the keys, Pisos Pro Medellín can take you from a bare concrete slab to a finished floor. We are flooring specialists with more than 15 years of experience, and much of our work is in new developments in Medellín, Envigado, Sabaneta and Rionegro.
In Colombia, many new apartments are handed over as obra gris: the shell is built, but floors and most finishes are left to the buyer. That gives you freedom to choose, yet it also hands you technical decisions the developer no longer makes, so this guide puts them in order: what to check on the slab, which floor suits each room and the sequence for the work.
- Slab moisture testing
- Recommended floor per room
- Order of work
Obra gris, obra blanca or fully finished: what you received
Each developer (constructora) defines the scope in its own way, so always compare against the sales specifications and the handover report (acta de entrega).
Obra blanca (white shell)
On top of the gray shell you get skim coat (estuco), paint, ceilings and often the bathroom tiling. Floors in the living areas and bedrooms are almost always still your responsibility.
Fully finished handover
The apartment arrives with floors, kitchen, bathrooms and carpentry complete. Here the question is no longer what to install but whether the floor you got works for you or you would rather replace it.
How long the slab must dry before flooring goes down
Concrete reaches its design strength at around 28 days, but drying is a different matter: excess water can take months to leave. In Medellín, with high ambient humidity, slabs dry more slowly than in drier climates.
That is why we go by a moisture meter rather than the calendar. As a reference, many hardwood and laminate manufacturers require less than 2% using the calcium carbide (CM) method, and glue-down vinyl must meet the limit on its own data sheet.
Porcelain tile tolerates a damper slab because it is set in mortar. Hardwood, laminate and microcement are unforgiving: if the slab is not ready, the advice is to wait or install a moisture barrier.
Leveling before installation
Slabs in gray-shell apartments are seldom flat. We run a 2-meter aluminum straightedge in several directions, since many laminate and SPC manufacturers call for deviations under roughly 3 mm over that length.
Large differences are corrected with leveling mortar; small ones with self-leveling compound at COP $35,000 to $75,000 per m². Both jobs are part of our subfloor repair and leveling service.
Before leveling, set the finished floor height for the whole apartment. That figure fixes the height of the doors, the bathroom thresholds and the base of the kitchen cabinets.
Which floor to install in each room
A common combination in new apartments is porcelain tile in the kitchen, bathrooms and laundry area, and SPC flooring everywhere else, with a transition strip at each change.
| Room | Recommended | Avoid | Reason |
|---|---|---|---|
| Living and dining room | SPC, porcelain tile, engineered hardwood | AC3 laminate | Heavy traffic and visual continuity |
| Bedrooms | AC4 laminate, SPC, hardwood, cork | Very cold porcelain if you prefer warmth | Comfort and less noise |
| Kitchen | Porcelain tile, SPC | Laminate and solid hardwood | Spills and frequent cleaning |
| Bathrooms | Slip-resistant porcelain tile | Any floating floor | Direct water and drains |
| Laundry area | Porcelain or ceramic tile | Hardwood and laminate | Washing machine leaks |
| Balcony | Outdoor-rated porcelain, WPC decking | Indoor flooring | Sun and rain |
| Study or home office | SPC, AC4/AC5 laminate | Carpet if you use a rolling chair | Wear from chair casters |
Order of work: floors, carpentry and paint
- 1
Utility lines and testing
Before covering the slab, finish any electrical, water and gas points that run through the floor. A pressure test now saves you from lifting a brand-new floor later.
- 2
Skim coat and first coat of paint
These are wet, dusty trades. Doing them first keeps paint drips and sanding dust off your new floor.
- 3
Moisture check and leveling
We test the slab, level wherever needed and let the self-leveling compound cure.
- 4
Bonded floors
Porcelain tile in the bathrooms, kitchen and laundry goes in before the cabinetry. That way the kitchen sits on the final floor.
- 5
Kitchen cabinets and closets
These are installed before any floating floor. A heavy cabinet sitting on laminate or SPC locks up its expansion.
- 6
Floating floors or hardwood
Laminate, SPC or engineered hardwood goes in once there is no wet work left anywhere in the apartment.
- 7
Doors, baseboards and final paint
Doors are trimmed to the finished floor height, baseboards (zócalos) are fitted and the last coat of paint goes on.
Typical flooring budget for a new apartment
Assumption: a 60 m² obra gris apartment with 45 m² of living areas and bedrooms, plus 15 m² of kitchen, bathrooms and laundry. Pick one option for the 45 m² and add the shared rows.
| Item | Quantity | Estimated range |
|---|---|---|
| Option A: AC4/AC5 laminate | 45 m² | COP $2,925,000 to $5,400,000 |
| Option B: SPC | 45 m² | COP $3,825,000 to $7,650,000 |
| Option C: engineered hardwood | 45 m² | COP $8,100,000 to $17,100,000 |
| Porcelain or ceramic tile in wet areas | 15 m² | COP $1,200,000 to $3,900,000 |
| Baseboards | 40 linear meters | COP $480,000 to $1,200,000 |
| Self-leveling compound, if the slab needs it | 60 m² | COP $2,100,000 to $4,500,000 |
Does not include bathroom wall tiling or a moisture barrier. See every price by material in our 2026 flooring price guide.
Let us plan the floors for your new apartment
We visit your apartment, measure the slab's moisture and level, and give you a written quote broken down room by room. If you have not bought materials yet, we help you choose them before the other contractors arrive.
Before you pick the floor for your new apartment, take a look at our other flooring guides.
Pisos Pro Medellín
Tv. 6 #45-115, El Poblado, Medellín, Antioquia, Colombia
Monday to Saturday: 7:00 a.m. to 9:00 p.m.
Sunday: 9:00 a.m. to 9:00 p.m.