Before you buy or build,
ask an engineer.
Air conditioning, pump, pool, heating, structure. You describe the problem, a mechanical engineer calculates it by the standard and returns a technical report — within 48 hours*, no site visit and no salesman pushing product.
*Turnaround depends on current demand and is agreed when the service is contracted.
What you get
It's not a guess. It's a calculation report.
The store salesman calculates BTU by square meter. The standard considers solar orientation, ceiling height, glazing, occupancy and equipment. The difference shows up in your electric bill every month — and in the compressor that dies early.
- Calculation per the applicable standard (ABNT, ASHRAE, ISO)
- Open calculation memory — you see where every number came from
- Equipment suggested by model, not by "more or less this"
- Estimated consumption and what the installer must meet
Calculation by square meter would suggest 9,000 BTU/h in this room. The west orientation and glazing area change the result — and an undersized unit runs at the limit all day.
How it works
From your problem to the right decision, in three steps.
A short form, no jargon
You describe the room or equipment in normal language. If any measurement is missing, I ask — and tell you exactly how to measure it.
Senior engineer, not an automated form
Mechanical engineer with a master's degree and 15+ years in industry applies the standard and runs the sizing. Simple cases come back in 24 to 48 hours.
If it doesn't solve it, you don't pay
You get the report, review it, approve it. Only then payment happens. Two rounds of revision included with any service.
Who runs the calculation
You talk to the engineer. Not a receptionist.
I'm Luiz Paulo Cruz, mechanical engineer with a master's degree and over fifteen years in mining, energy and railway infrastructure — structural calculation, equipment design and standards compliance. The same criteria I use in industrial projects is what I apply when someone asks me which air conditioner to buy.
Luiz Paulo Cruz · M.Sc. Mech. Eng. · Belo Horizonte, Brazil
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Structural calculation, reports and industrial design.
The same engineering that served mining, rail and energy for over fifteen years — now available on demand, without going through an entire firm.
Projects adapted to the standard of the requesting country. ART issued separately when the service requires registered technical responsibility in Brazil.
Services
From the room that won't cool to the warehouse that needs calculation.
Your home
What the store won't calculate and the installer won't guarantee.
- Air conditioning sizing
- Garden pump, cistern and well
- Pool pump and filtration
- Solar heating and heat pump
- Shower pressurization
- Second opinion on received quotes
Report and opinion
When you need someone to sign off.
- Point structural verification
- Report for HOA or insurance
- Independent technical opinion
- Third-party design review
- Equipment failure analysis
- ART issued on demand
Industry and construction
Fixed scope or ongoing support.
- Metal structure and platforms
- FEA / finite element analysis
- Piping and supports
- Special machinery and equipment
- Reverse engineering and detailing
- Hourly or monthly consulting
Each case is quoted individually based on scope, timeline and applicable standard. You receive the price before any charge — and only pay after approving delivery.
Guide
Air conditioner acting up?
A guide to the most common causes of an AC that won't cool, leaks water, or trips the breaker — and when it's a design problem, not maintenance.
Quote
Tell me your problem. I'll respond within 24 hours.
The more detail, the faster the quote. You don't need to know technical terms — describe it like you would to a friend.
Frequently asked questions
Questions from those just getting started.
Do I need a site visit?
In most residential cases, no. You provide the measurements and send photos via WhatsApp — that's usually enough for sizing. When the case requires an on-site inspection (existing structure report, for example), I'll tell you before any charge.
How much does it cost?
Each case is quoted individually based on scope, timeline and applicable standard. You get the price before any commitment and only pay after approving delivery. Simple sizing services cost well below what a site visit usually costs.
Do you issue ART?
Yes, on demand. ART doesn't come built into the standard price because most residential services don't require registration — charging everyone for something only some need would increase costs unnecessarily. When your case requires it, the price is quoted separately.
Do you serve outside Brazil?
Yes. Calculation is adapted to the standard of the requesting country — ASHRAE, ISO, Eurocode, AISC, ASME, among others. Service is available in Portuguese, English or written Spanish.
How long until I get it?
Simple sizing: 24 to 48 hours. Reports and structural verification: 3 to 10 days, depending on survey needs. Full projects have a deadline in the proposal. If you're in a rush, let me know — there's an expedited option.
What if the report doesn't solve my problem?
You don't pay. Payment happens after your approval, not before. Every delivery includes two rounds of revision at no cost — if something was imprecise or missing, it gets corrected.