How to Choose the Right AC Size for Your Home in Saudi Arabia & MENA

Every summer, the same mistake plays out across thousands of apartments in Dubai, Riyadh, Cairo, and Casablanca: a brand-new AC unit is installed, the homeowner turns it on, and the room still feels warm at 2pm. Or the opposite — the unit is oversized, it short-cycles, and the humidity never drops even though the temperature does.

The fix is simple, but surprisingly few people know it before they buy: AC size is a calculation, not a guess.

Why AC sizing matters more in MENA than anywhere else

Western sizing guidelines — the ones that come with most AC spec sheets — are calibrated for temperate European or North American climates. They assume moderate outdoor temperatures, low solar radiation, and walls that don't absorb heat all day.

None of that applies here. In Dubai in July, outdoor temperatures regularly exceed 42°C. A south-facing apartment on the top floor of a building absorbs solar radiation from three surfaces simultaneously. The ASHRAE standard used globally needs at least a +10% adjustment for MENA conditions — and more for top-floor, south-facing rooms in Gulf cities.

If you use the generic "12,000 BTU per 15 m²" rule of thumb without adjustments, you'll consistently undersize.

The three numbers you need to understand

BTU/hr (British Thermal Units per hour) — the most commonly cited unit. A standard 1-ton split unit is 12,000 BTU/hr. A 1.5-ton is 18,000 BTU/hr. A 2-ton is 24,000 BTU/hr.

Tons — a legacy unit still widely used in the Gulf and Egypt. 1 ton = 12,000 BTU/hr.

HP (Horsepower) — common in Egypt and parts of the Maghreb. 1 HP ≈ 9,000 BTU/hr, though brands sometimes round differently.

If you're comparing quotes from multiple technicians, always confirm which unit they're quoting in. A "2 HP" unit and a "2 ton" unit are not the same capacity.

What actually affects the BTU calculation

Room dimensions — length × width × ceiling height gives you the volume to cool. Ceiling height matters more than people expect: a 3.2m ceiling (common in older Levant apartments) increases the required capacity by roughly 15% vs. a 2.6m ceiling.

Sun exposure — a shaded north-facing room needs significantly less cooling than a south-facing room with afternoon sun hitting it directly. This is often the single biggest variable.

Floor level — top floor apartments receive radiant heat through the roof in addition to the walls. Ground floor apartments are usually cooler. The difference can be 10–15% of required capacity.

Number of occupants — each person adds roughly 500 BTU/hr of heat load.

City — ambient temperature baselines vary significantly across MENA. Riyadh summer peaks are different from Casablanca summer peaks. Any accurate calculator should account for this.

Use our free BTU calculator

We built a calculator that accounts for all of the above — calibrated specifically for MENA conditions, with per-city adjustments for the 8 countries on the platform.

It takes about 30 seconds to use and gives you the result in BTU, Tons, and HP simultaneously. It also recommends the unit range you should be shopping for, so you can walk into a conversation with a technician already knowing what you need.

Try the free AC BTU Calculator →

What to do once you have your number

Once you know the right BTU range, the next step is finding a verified HVAC technician who will quote you correctly — not upsell you to a larger (and more expensive) unit, or undersell you to keep the invoice low.

On SouqHouse, you can search for verified AC technicians in your city, review their profiles and past work, and contact them directly.

Find a verified AC technician near you →

Quick reference: typical BTU ranges by room type

These are starting points for a well-insulated room on a middle floor with moderate sun exposure. Adjust upward for top floors, south-facing rooms, and Gulf cities with extreme summer peaks.

Room type	Typical size	Starting BTU	Typical unit
Small bedroom	10–14 m²	9,000–12,000	0.75–1 ton
Standard bedroom	15–20 m²	12,000–18,000	1–1.5 ton
Large bedroom / study	20–28 m²	18,000–24,000	1.5–2 ton
Living room	25–40 m²	24,000–36,000	2–3 ton
Open plan living/kitchen	40–60 m²	36,000–48,000	3–4 ton

For top-floor rooms or south-facing spaces in Dubai, Abu Dhabi, Riyadh, or Doha, add 15–20% to these estimates.

One last thing

The calculator gives you a target capacity. It doesn't account for the quality of your existing ductwork (for ducted systems), the condition of your wall insulation, or the efficiency rating of the unit you choose. For a room that's never properly cooled despite having an appropriately sized unit, the problem is usually one of those three — not the BTU number.

If you've already installed what the calculator recommends and the room still isn't cooling correctly, post a job on SouqHouse and describe the symptoms — a good HVAC tech can diagnose the real cause in one visit.