Renting shouldn't mean sweating through every heatwave. German tenancy rules limit what you can permanently change about a flat, but they leave the door wide open for portable, removable cooling — which is exactly what you want anyway, because it moves with you. This guide covers what's allowed, what actually works in a rental, and how to cool without risking your deposit.
What can a landlord actually forbid?
In general, a landlord can restrict permanent alterations — drilling through walls or window frames, installing a fixed split air conditioner, or anything that changes the building's structure or facade. What they typically can't stop is your use of portable, freestanding appliances: a fan, an evaporative air cooler, or a mobile air conditioner vented through a removable window kit. The line is roughly "does it leave a mark or alter the building?" If the answer is no, you're usually fine — but always check your specific lease, and when in doubt, ask.
No-drill cooling that leaves no trace
The whole renter toolkit is removable:
- Fans (tower, pedestal, table) — zero installation, just plug in. See the fans page.
- Evaporative air coolers — plug-in, no hose, no fixings. See air coolers.
- Mobile air conditioners — the only portable option that truly refrigerates, vented through a no-drill window sealing kit. See mobile ACs.
None of these require permission in normal circumstances, and all of them come with you when you move.
Window sealing kits: venting an AC without drilling
A mobile air conditioner needs to send hot air outside, and renters do this with a window sealing kit — a fabric or panel insert that fits the window opening, lets the hose pass through, and seals the rest so the heat you're removing doesn't leak back in. It installs in minutes, needs no tools, and removes cleanly. This is what makes a mobile AC genuinely renter-friendly: full cooling, no holes, deposit intact.
Cooling a small studio
In a compact studio, you often don't need much. A single tower or pedestal fan, or an air cooler for dry heat, can keep the space comfortable and tucks away when not in use. If the room bakes — top floor or lots of glass — a compact mobile AC with a window kit gives you real temperature control without permanent changes, and it stores in a cupboard over winter.
North-facing vs south-facing flats
Your flat's orientation changes the strategy. A north-facing flat stays cooler and may need only a fan and good night ventilation. A south- or west-facing flat takes direct sun for hours and heats up fast, so shading the windows from outside and adding active cooling (air cooler or mobile AC) makes a bigger difference. Either way, shade before the sun hits and ventilate only when it's cooler outside.
Choose cooling you can take with you
The smartest renter buy is gear that earns its keep across multiple flats. Fans, air coolers, and mobile air conditioners are all portable, so the money you spend follows you to your next home instead of being left behind in a wall. That makes the decision less about a single summer and more about a piece of kit you'll use for years.
Find renter-friendly cooling in stock
All the renter-safe options — fans, air coolers, and mobile ACs with no-drill kits — are exactly what this site tracks. Check the live availability map to see what's in stock near you right now, reserve for pickup, and set an alert if your nearby stores are sold out.