Describe the room and the retained installations
State whether the layout stays in place, how the shower is heated and which pipes, circuits and shared connections remain. Keeping the WC position does not prove that the existing drain can be reused. Have competent installers inspect accessible parts and identify questions that need opening-up before a fixed proposal can be reliable.
Choose the WC, basin, taps, shower, screen and furniture or establish explicit allowances. Give installers the actual shower model, voltage and power specifications for assessment; do not assume that a new electric shower can use any existing circuit. The reform-plan approach in council guidance helps allocate the responsible professionals and building interfaces.
Measure surfaces and the purchase quantity
For an invented rectangular room of 2 × 2.5 m, perimeter is 9 m. Wall tiling to 2.4 m gives 21.6 m². Deduct a 0.8 × 2 m door and a 1 × 0.6 m window: walls are 19.4 m². Add the 5 m² floor to obtain 24.4 m². Agree whether openings and returns are deducted in the actual quote; the calculation is not a universal measurement convention.
A chosen 10% cutting allowance gives 26.84 m² to buy. With 1.6 m² packs, round up to 17 packs, or 27.2 m². At an invented final supply price of R$80/m², tiles cost R$2,176. Confirm batch, shade, size, return conditions and delivery. The paid supply quantity can differ from the measured area used to price laying.
Ask for the complete layers, not just a tile finish
The IBI recommends a waterproofing project; its technical guide distinguishes preparation, coordination, protection and checks. Ask the designer to identify the appropriate system, drains, junctions and treatment of penetrations. A product name or a line reading “waterproof bathroom” does not specify those interfaces.
- Identify removal and repairs to the existing substrate.
- Describe the waterproofed areas and their junctions under the project.
- Allocate mortar, grout, trims and installation consumables.
- Agree inspection and appropriate testing before covering, with the responsible professional.
- Record curing and first-use conditions for the chosen system.
Do not conduct an improvised flood test or prescribe a universal coating from this example. The installer and designer must define a suitable method, duration, loading and corrective action for the actual construction.
Read a complete funding example
| Item | Amount |
|---|---|
| Protection, demolition and agreed waste route | 1 100 |
| Local water and drainage work | 2 200 |
| Defined electrical work | 1 000 |
| Substrate repair and preparation | 1 200 |
| Specified waterproofing supply and application | 1 500 |
| Tile laying labour | 1 800 |
| Tile supply: 27.2 m² at 80 | 2 176 |
| Mortar, grout and profiles | 650 |
| Sanitaryware and tap supply | 2 200 |
| Glass screen supplied and installed | 1 300 |
| Other fixture fitting and final checks | 700 |
| Final cleaning | 300 |
| Defined work and supplies | 16 126 |
| Outside professional allowance | 800 |
| Chosen reserve: 10% of defined work and supplies | 1 612.60 |
| Total funding | 18 538.60 |
The glass screen line includes its fitting; the R$700 line excludes that work. Waterproofing includes its specified materials, while tile mortar and grout sit in the R$650 line. Confirm such boundaries in real proposals. R$800 is an outside provisional professional amount, not a fixed public fee or proof that all required services have been priced.
Compare exclusions and control product changes
The CDC estimate rules and Procon’s itemisation guidance make a useful basis for questions about labour, materials, payment and dates. Obtain corrected written offers for the same scope. An offer excluding tile supply cannot be compared directly with the R$16,126 package above. Do not invent the price of an omitted repair to make a contractor’s total look complete.
If the same 27.2 m² of tiles changes from R$80 to R$95/m², the extra is R$408. Using reserve leaves R$1,204.60; preserving it increases funding to R$18,946.60. This assumes no changed cutting, laying or delivery work. Price those effects separately if the product choice changes them.
Plan loss of the bathroom and the handover
- Confirm shutdowns, permitted access and how long the only bathroom will be unusable.
- Inspect the agreed hidden work before covering.
- Demonstrate drainage, taps, screen and relevant installation checks.
- Collect invoices, product instructions, applicable technical records and the final specification.
- Record unfinished tasks and defects with location, responsible party and correction date.
Allow for temporary living arrangements if safe use cannot be maintained. Keep the accepted scope, choices and payments in Reno Pro, with technical reports held by their authors. The quote should purchase a usable room with defined checks, not merely an attractive visible finish.
Sources, date and scope
- Presidência da República — Código de Defesa do Consumidor — arts. 39 VI e 40
- Procon SC — Orçamento para serviços — custos discriminados
- Instituto Brasileiro de Impermeabilização — Selo de Qualidade IBI — Projetista
- Instituto Brasileiro de Impermeabilização — Guia de aplicação da norma de desempenho para impermeabilização
- Crea-RJ — Síndicos — orientações para reformas e manutenções
Sources checked on 19 October 2026. Unless stated otherwise, the local example is São Paulo city; check municipal and condominium rules for the actual address and work. Teaching figures are invented final amounts in Brazilian reais, not surveyed prices, offers or official fees. Projects in different articles are independent. Technical assessment, professional records and authorisations remain with the competent people.