Most renovation problems are predictable — they are made by nearly everyone, on nearly every project. The good news is that knowing about them in advance is enough to avoid most of them. Here are the eight that cost the most.
1. No budget buffer
The number-one mistake: planning a renovation with no reserve. Unexpected costs appear on almost every project — a hidden moisture problem, an installation that needs replacing, tiles that crack during laying. Without a buffer, every surprise becomes a crisis.
The rule: always set aside 15–20% of the total budget as a reserve. If you don't need it — great. If you do — you'll be grateful it's there.
2. Wrong order of works
Laying parquet before the electrician runs cables under the floor. Painting before the screed is dry. Fitting the bathroom door before the tiles are laid. Each of these mistakes means redoing finished work — at full cost, twice.
The correct sequence is: demolition → rough construction → installations → screed → tiles → plastering → parquet → joinery and sanitary ware → painting → final details. Read more in Flat renovation — the correct order of works.
3. Rushing the drying process
Screed, waterproofing and skim coat all need time to cure properly. Rushing this is one of the most common causes of cracks, peeling tiles and floor problems that appear months after the renovation.
Warning: screed at 4 cm thickness needs a minimum of 28 days to dry before anything is laid on top. Waterproofing must cure for 24–48 hours before tiling begins. These waits cannot be shortened.
4. Choosing the cheapest tradesperson without checking references
A significantly lower price than everyone else's is not always a bargain — it often means inexperience, poor materials or hidden extras that surface near the end. The cheapest offer frequently turns into the most expensive renovation.
Before hiring anyone, ask to see previous work and speak to at least one past client. A good tradesperson will have no problem connecting you.
5. Buying materials without seeing a sample first
Tiles that look one colour on a screen look different in the flat. Paint that seems right in the tin looks different on the wall. Parquet that looks warm in the showroom can look cold under your lighting conditions.
The rule: always get a physical sample — a tile, a strip of parquet, a painted patch — before ordering the full quantity. This is free, or costs very little, and can save you from a decision you'll regret for years.
6. Buying too little — or too much — material
Underbuying means mid-project scramble, possible delays, and the risk of a different batch shade. Overbuying wastes money on material you'll never use.
- For tiles and parquet: order 10% more than the calculated surface area (for cuts and breakages)
- For paint: 10% extra is sufficient if applying the same colour throughout
- For wallpaper: 15% extra, because pattern matching wastes more
7. Ignoring moisture before finishing works
A damp wall that gets skim-coated and painted will show mould within a year. A wet subfloor that gets parquet laid on it will cause the parquet to buckle within months. Moisture problems do not go away on their own — covering them only postpones and worsens the outcome.
Tip: before any finishing work, check that walls and floors are genuinely dry. A basic moisture meter costs 2,000–4,000 RSD and can save you tens of thousands in repairs.
8. No documentation
After the renovation, nobody can remember where the pipes run, where the cables are hidden or what's behind the tiled wall. When a pipe leaks or a cable needs tracing three years later, the lack of photos costs real money.
The fix: before covering installations (pipes, cables, underfloor heating), take photos. Keep them. They take a minute to shoot and can save hours of demolition work later.
Looking for a reliable tradesperson for your renovation? On Brzix you can find tradespeople with real client reviews — electricians, plumbers, tilers, painters and more.
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