Keep Your Apartment Cool: Shutters, Awnings, Solar Film

To keep an apartment cool in summer, stop the sun from reaching the glass during the day with shutters, an outdoor awning or solar film, close everything as soon as the outside air is warmer than inside, then ventilate fully at night. A fan helps you cope with the heat, but it does not lower the room temperature.

Is your flat still unbearable despite all this, in Paris or the inner suburbs? Call +33 1 89 70 15 36 (01 89 70 15 36 from a French phone), 7 days a week, 24 hours a day, or write to us through the contact page or WhatsApp. Many of our plumbers speak English. Our guide to air conditioning installation in Paris helps you decide whether AC is the right answer for your home.

Planning air conditioning? Installation, servicing and repair, building approval included: see our air conditioning service in Paris.

This guide brings together what really works in a Paris apartment: sun protection, the ventilation routine, using a fan properly, the weak points of Haussmann buildings, and what the co-ownership (the building's owners' association, run by a property manager called the syndic) can do.

Why Paris apartments overheat

Several factors add up during a heatwave.

• The urban heat island. Asphalt, stone and zinc roofs absorb sunshine all day and release the heat at night. The city stays warmer than the countryside around it, especially at night, so the outside air no longer cools your flat. Our article on the urban heat island effect in Paris explains the phenomenon in detail.
• Large windows. Great for light in winter, they let in a lot of radiation in summer, especially single glazing, still common in older buildings.
• The top floor under zinc. The roof heats up strongly in the sun and passes that heat to the ceiling below, all the more because the roof space is rarely insulated.
• Cut-stone walls. Their thermal mass helps at the start of a heatwave, but once loaded with heat they give it back for days. That is why you should act from day one.
• Paved inner courtyards. Surrounded by stone, with no plants, they trap hot air.
• Single-aspect flats. In a studio where every window faces the same way, a cross draught is impossible.

Block the sun before it reaches the glass

Outdoor protection always beats indoor protection. An indoor curtain or blind stops the light, but the radiation has already crossed the glass and heated the air between the window and the fabric. An outdoor shutter or awning stops the sun before it reaches the glass.

The technical figure to ask for is the solar factor (in French, facteur solaire, Fs): the share of solar energy that passes through the window and its protection, from 0 (nothing gets through) to 1 (everything does). The lower, the better. For comparable products, outdoor protection reaches a much lower solar factor than indoor protection. Ask the seller for this value to compare.

Shutters, awnings, film: which protection to choose

Roller shutters and louvred shutters

Closed, they block almost all radiation. They also help with noise and security. The downside: no daylight. Best choice for a bedroom where someone sleeps during the day.

Awnings and drop-arm blinds

A horizontal awning suits balconies and south-facing windows: it blocks direct sun while letting in daylight from the sky. A vertical drop blind works better on east and west facades, where the sun comes in low. The right choice for a living room or home office you use during the day.

Brise-soleil (fixed louvres)

Fixed or adjustable slats built into the facade. Very effective on south walls, they block the high summer sun and let in the low winter sun. In a co-ownership building they need a vote at the general meeting, usually as part of a facade renovation.

Solar film on the glass

The film is applied to the inside of existing glass, with no building work. It is often the only option where outdoor protection is refused.

• Reflective film sends radiation back outside. The most effective in summer, with a slight mirror effect and a somewhat darker room.
• Tinted or absorbing film absorbs part of the radiation but releases some of it indoors. Less effective against heat.

Be careful with double glazing: the wrong reflective film can cause thermal stress in the glass and crack it. Check compatibility with your glazing before fitting.

Indoor blinds and thermal curtains

Screen blinds, venetian blinds, curtains with a reflective lining: a moderate gain, but easy to fit and no permission needed. Close them early, before the glass heats up, and choose a light colour facing the window.

Quick comparison

• Outdoor roller shutter. Summer effectiveness: very high. Fitting: building work. Co-ownership approval: yes (colour, model).
• Outdoor awning. Summer effectiveness: high. Fitting: building work. Co-ownership approval: yes (colour, permission).
• Reflective solar film. Summer effectiveness: medium to good. Fitting: very easy. Co-ownership approval: no (indoors).
• Indoor screen blind. Summer effectiveness: medium. Fitting: very easy. Co-ownership approval: no.
• Thermal curtain. Summer effectiveness: low. Fitting: very easy. Co-ownership approval: no.

The best strategy in a Paris flat: outdoor protection wherever it is allowed, and solar film on the windows that have none.

The routine that changes everything: close by day, ventilate by night

This is the most effective habit, and many Parisians do the opposite by opening windows during the day "to get some air". The idea is simple: cool the walls and floors at night, then seal the flat in the morning to keep that coolness as long as possible.

Morning: close everything early

Put a simple thermometer near a window. As soon as the outside temperature rises above the inside temperature, close:

• the windows, fully, not left ajar;
• the shutters and blinds on every sun-facing window;
• heavy curtains on windows without shutters (courtyard side, roof windows).

During the day, leave everything shut and keep inside doors open so the cool air circulates. One exception: close the door of a room in full sun so it does not heat the rest of the flat.

Evening and night: ventilate as much as possible

As soon as the outside air drops below the inside temperature, open wide:

• open several windows on opposite facades (street and courtyard, east and west) to create a cross draught;
• put a fan in front of an open window, facing out, to push hot air out;
• leave windows open all night if it is safe: the air is coolest towards the end of the night.

Adjust to the orientation

• East: the sun arrives early. Close at sunrise.
• South: the sun is high in the middle of the day. Protect this facade most carefully.
• West: late-afternoon sun hits when the air is already hot. An unprotected west window is the worst case: awning or film first.
• North: little or no direct sun. Your refuge room for working or resting during the day.

Single-aspect flats

Without a cross draught, place a fan facing the open window and blowing outwards: it pulls air through the flat. If the building's hallway is cooler, leave the front door ajar in the evening (with your neighbours' agreement if the landing is shared).

Common mistakes

• Opening windows during the day when it is hotter outside.
• Closing the windows but not the shutters: the sun goes through the glass.
• Ventilating too late in the evening, or closing up too early while the morning air is still cool.
• Running a fan with the windows shut and thinking it renews the air.

Cut the heat produced indoors

• Move the oven, tumble dryer, dishwasher and ironing to the evening.
• Leave space around the fridge, which releases heat at the back.
• Switch to LED bulbs, which give off far less heat than filament bulbs.
• Unplug devices on standby (internet box, chargers, TV).

Fan or air conditioner: what each really does

A fan does not cool the air. It creates a flow that speeds up the evaporation of sweat, which feels cooler. It uses little power, needs no installation or permission and does not bother the neighbours. Its limits: once the air it moves is warmer than your skin, it stops helping, and it can do nothing against walls loaded with heat after several days of heatwave. It remains very useful at night to push hot air out.

A ceiling fan is the best fan for a Haussmann flat: quiet, suited to large rooms, and the high ceilings (often 2.80 to 3.20 m) leave room to fit one.

An evaporative air cooler blows air over a wet pad. It only works well in dry air, which is rare in Paris in summer. It is not an air conditioner.

A portable air conditioner is noisy and inefficient, and its exhaust hose means leaving a window ajar. It is a stopgap.

A split air conditioner is the only device that actually lowers a room's temperature. It needs professional installation and, in a co-ownership building, approval for the outdoor unit. Our article on co-ownership rules for air conditioning explains the steps.

A good habit if you have AC: set a moderate temperature and combine it with a ceiling fan. It feels better and uses less power. Our article on air conditioning consumption and impact covers the right settings.

When air conditioning becomes necessary

• Older people, babies, people with heart or breathing conditions, or on certain medications.
• Several nights in a row without any cooling.
• A flat with no cross draught, facing south or west, on the top floor.
• Long days working from home in an overheated room.

Insulating a Haussmann apartment against heat

1. Roof and roof space

The biggest gain for the top floor. Depending on access: insulation under the roof slopes (rock wool, cellulose wadding), external insulation when the roof is redone, or a reflective screen under the covering. If the co-ownership redoes the roof, a high-reflectance coating on the zinc (a "cool roof") reduces heating.

2. Windows

• Replacement with high-performance double glazing: the most effective, but street-side windows need permission in protected areas.
• Secondary glazing: a second pane on the inside, leaving the original frame untouched.
• Reflective solar film: reversible, no building work.

3. Walls

External insulation is usually ruled out on a protected Haussmann facade. Internal insulation costs floor space, which matters in a small flat. Thin insulating plasters are a compromise.

Solutions that respect an old building

Indoor shutters or louvres, discreet blinds, film, a ceiling fan, and vents in interior doors so air moves at night even with doors closed. Indoor solutions avoid facade rules.

Grants

Grants exist under conditions for insulation (MaPrimeRénov', energy saving certificates known as CEE, the zero-interest eco-loan), with a contractor holding the RGE label for the work concerned. Our article on plumber certifications in France explains how to check it. Insulation improves comfort in both summer and winter.

Greening your balcony and courtyard

Plants cool the air in two ways: the shade of their leaves, and evapotranspiration, the water they release through their leaves using the sun's energy. The effect is real close by, especially in an enclosed space like a courtyard, but it does not replace sun protection in a heatwave.

South-facing balcony: climbers on a trellis in front of the window (star jasmine, passion flower, Virginia creeper) to act as a screen, and Mediterranean plants that handle heat (lavender, rosemary, sage, potted olive tree).

North-facing or shaded balcony: ferns, hostas, heucheras or ivy, with dense foliage.

Tips: plant densely, prefer large leaves, use deep planters, check the balcony's load limit and water in the evening or early morning. Mulch and drip irrigation save water.

The building's courtyard is the biggest lever. Trees if the structure allows, planters along the walls, a green pergola, permeable surfaces instead of asphalt. It is a collective project: take it to the syndic with a plan, a landscaper's quote and a maintenance plan, check whether the courtyard sits on a slab or on open ground, plan the watering, then ask for it to be put on the general meeting agenda. On the street side, the City of Paris issues a permis de végétaliser (greening permit) for planting at the foot of the facade.

What to know in a co-ownership building

• The facade is a common part. Anything visible from the street (shutter, awning, louvres) must follow the co-ownership rules, which often set the colour and model.
• An outdoor awning usually needs approval from the general meeting. Ask your syndic before buying, and the town hall if the building is in a protected area, where the opinion of the Architecte des Bâtiments de France (the state heritage architect) may be required.
• A tenant can usually fit indoor protection alone. Outdoor protection needs the landlord's and the co-ownership's agreement.

FAQ

Should I open or close the windows during the day when it is hot?

Close them, shutters included, as soon as the outside air is warmer than inside. Opening them lets hot air in and heats the walls. Open wide again in the evening, once it is cooler outside.

Does solar window film really work?

Yes, if it is reflective. It clearly reduces heat gain, with no building work, and comes off easily. Check compatibility with double glazing before fitting.

Can I put up an outdoor awning in a co-ownership building without permission?

In the vast majority of Paris co-ownership buildings, no. The facade is a common part: you need the general meeting's approval and must follow the rules. In protected areas, a town hall procedure is often added.

Roller shutter or awning for a south-facing window?

A roller shutter for a bedroom, because it blacks out everything. An awning for a living room or office, because it blocks direct sun while keeping daylight.

Is a fan enough during a heatwave?

For a healthy adult and moderate heat, often yes. With repeated nights without cooling, in a flat with no cross draught, or for a vulnerable person, it is no longer enough and air conditioning becomes a real solution.

When these steps are not enough

Réseau Tubulure works in Paris and the inner suburbs (92, 93, 94), 7 days a week, 24 hours a day, and gives you honest advice: protection and habits first, air conditioning if your home needs it. Many of our plumbers speak English.

• Phone: +33 1 89 70 15 36 (01 89 70 15 36 from a French phone)
• Form: contact us
• WhatsApp: from the button on the site

To go further, read our guide to air conditioning installation in Paris.