Shop & Office Renovation: Steps & Permits

Before work begins: survey and design

Every successful shop renovation starts long before any trade arrives on site. The first step is a thorough survey of the existing space: dimensions, current MEP runs, structural layout, and condition of floors, walls, and ceiling. Without this data, no design or estimate will be accurate.

Once surveyed, your architect or engineer (or contractor, if you go with full project management) creates a space plan. This shows furniture placement, equipment zones, customer and staff areas, and traffic flow. Simultaneously, the MEP engineer designs new electrical, water, heating and cooling systems from scratch: where cables run, where outlets and switches go, how water and drainage flow, and where HVAC air is distributed.

Other key design studies at this stage include lighting (critical for retail to show products clearly), acoustics (if you have many customers or staff), and thermal comfort. Good design at this stage costs time and money upfront, but saves significantly during construction by preventing surprises and changes.

What permits are required for shop renovation?

Greece uses two main permitting paths for renovations. Most small to medium interior renovations fall under "small-scale works approval" (έγκριση εργασιών μικρής κλίμακας), which is a streamlined process for work that doesn't affect the building's load-bearing structure or significantly alter the floor plan.

If your renovation involves demolishing load-bearing walls, major structural changes, or extensive MEP upgrades that could affect building stability, you need a full building permit (οικοδομική άδεια). A qualified contractor or engineer will classify your scope correctly.

Beyond structural permits, some uses require additional approvals. A food business, for example, may need environmental or health permits. Small-scale works approval and building permits are handled as part of a professional project management service, so your contractor manages the administrative process.

Work phases: step by step

Once permits are in place, trades don't start randomly. There's a logical sequence that maximises efficiency and quality.

1. Preparation and demolition

The first trades remove existing equipment and strip non-structural elements. This includes removing old finishes (paint, wallpaper), pulling out fixtures, and disconnecting old electrical and plumbing systems that will be replaced. All waste is properly removed from site.

2. MEP systems (electrical, plumbing, HVAC)

Once the space is cleared, new systems are installed. Electricians run new cable conduit and cabling, install panels, switches, outlets and lighting. Plumbers install new water supply lines, waste and vent pipes. HVAC contractors (if applicable) set ducts and equipment for heating, cooling or ventilation. This phase requires careful coordination between trades to avoid conflicts and ensure systems are properly tested before walls close.

3. Flooring and ceilings

With MEP rough-ins complete, flooring is laid (concrete, tile, polished concrete, vinyl or wood, depending on your choice). Ceiling work happens in parallel: suspended ceilings, insulation, or exposed finishes, along with integration of lighting and any return-air openings.

4. Walls and finishes

Walls are plastered or repaired as needed, then painted or finished. Trim, kickboards, shelving brackets, and any cladding systems are installed. This is when the space starts to look recognisable.

5. Equipment and handover

Final stages include installation of built-in furniture, specialised equipment (retail shelving, office fit-outs, kitchen or service counter installations), door hardware, and decorative elements. The space is then inspected, cleaned, and handed over ready for trading.

Keeping the shop open during renovation

Many retailers can't afford to close for months. In these cases, we schedule work during off-hours (typically evenings and nights) or divide the shop into zones so part stays open to customers while another is under work.

This approach is more complex and costly (night shifts, temporary barriers, higher labour costs) but it's feasible. The key is planning this from the start so trades know their constraints and can schedule accordingly. A coordinated contractor is essential for this to work smoothly.

Office renovations: what's different

Office renovations share many steps with retail, but have distinct requirements. Acoustics matter far more in offices: open-plan layouts need sound-absorbing materials and strategic zoning to avoid constant noise. Partitions must be designed not just for privacy but for sound control.

Data infrastructure is critical. Office networks need structured cabling runs, equipment rooms, and thoughtful outlet placement for computers and phones. Even if you rely on WiFi, your building must accommodate servers, security systems, and telephony equipment. Lighting is also crucial: poor lighting causes fatigue and reduces productivity. Consider task lighting, glare control, and sufficient lumens for screen and paper work.

How long does renovation take? A realistic view

There's no single answer. A small shop (50 sq m) with straightforward updates can be done in 4 to 6 weeks. A large retail or office space (300 sq m) with complex MEP systems and extensive finishes may take 12 to 16 weeks or more.

Factors affecting duration include:

• Size and complexity of the space
• Extent of MEP demolition and replacement
• Weather (humidity affects paint and concrete cure time)
• Availability of materials and skilled labour
• Unforeseen issues discovered during work (hidden damage, structural decay, asbestos)
• Whether the shop must stay partially open

Unforeseen issues are common in older buildings and can extend timelines by weeks. This is one reason a contingency period is wise; aggressive deadlines often lead to poor quality or costly overruns.

What drives renovation cost?

Cost is shaped by many variables. There's no formula saying each square metre costs X. A small shop can be expensive if it has complex systems; a large shop can be affordable if work is straightforward.

Key cost drivers include:

• Space size: Larger spaces cost more overall, though unit cost may not scale linearly.
• Finish quality: Premium flooring, paint, and lighting cost more but last longer. Basic options are cheaper but may need replacement sooner.
• MEP scope: If systems are old or inadequate, replacing all electrical, plumbing and HVAC is expensive. Retaining serviceable systems reduces cost.
• Building condition: Old buildings often hide damage. Once opened up, water damage, structural decay, or asbestos may be found, adding cost and time.
• Special requirements: Hazardous material removal, structural reinforcement, or specialised systems (kitchen extraction, data centre cooling) add cost.

The best approach is to get a detailed breakdown from your contractor showing quantities, labour, and materials for your specific scope. Ask for references on similar projects.

Common mistakes to avoid

We've seen several patterns that lead to trouble. Most are avoidable:

• Starting without a proper survey and design: Rushing into work without detailed plans causes confusion, rework, and cost overruns. Invest in the upfront design phase.
• Hiring multiple uncoordinated trades: When each trade acts independently with no central coordination, delays and conflicts multiply. A single point of accountability is essential.
• Skipping or delaying permits: Time "saved" by ignoring permits is usually lost later to fines or rework. Get permits approved from the start.
• Choosing suppliers by price alone: The cheapest isn't always the best. Check references, site visits, and track records.
• Unrealistic timelines: Promising a 4-week job in 2 weeks leads to chaotic management and poor results. Build in a realistic buffer.
• Ignoring MEP maintenance: Once systems are installed, they need regular testing and inspection. Poor commissioning leads to failures months later.

Why one contractor beats multiple trades

Some business owners try to save by hiring their own electrician, plumber, painter and so on. They think they avoid paying a project manager. Often, this strategy backfires.

A full-service contractor or project manager has standing relationships with the same teams, understands their work style, and can sequence trades efficiently. If something goes wrong, there's one person accountable. When you hire separate trades, you're responsible for coordination. Delays in one trade ripple to others. Quality issues fall between trades (is it the electrician's fault or the drywaller's?). What you save in management fees, you often lose to delays and rework.

Professional project management is especially valuable for renovations, where hidden issues are common and coordination is tight.

Sources: National Registry of Procedures (mitos.gov.gr) · gov.gr

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