Picking a sliding door sounds simple until you see the options: aluminium, PVC, timber, single track, double track, lift-and-slide, double glazing, triple glazing. In Brussels, where homes range from narrow 19th-century townhouses to 1970s apartment blocks and new low-energy builds, the right choice depends on your building, your budget and how you use the door every day.
This guide explains the main choices in plain terms so you can compare quotes with confidence.
Start with how you will use the door
Before looking at materials, answer three questions:
- Which room does it serve? A living room terrace door is used daily and shapes the look of the room. A basement or garage door matters less for appearance and more for durability.
- Which way does it face? A south-facing door gets strong sun and heat in summer. A north-facing one loses heat in winter and stays damp longer.
- How wide is the opening? Wide openings need stronger frames and better rollers, and they cost more.
The four main frame materials
Aluminium
Aluminium is the most popular choice for modern sliding doors because it is strong enough to hold large glass panels in slim frames. That means more light and a cleaner look.
- Good: slim profiles, long life, low maintenance, wide colour range
- Watch for: cheaper frames without a thermal break lose heat quickly. Always ask for a thermally broken profile.
- Typical lifespan: 30 years or more with basic care
PVC (uPVC)
PVC offers good insulation at a lower price. Frames are thicker than aluminium, so you get slightly less glass.
- Good: affordable, good thermal performance, easy to clean
- Watch for: large panels may need steel reinforcement, and some colours can fade or yellow over time in strong sun
- Typical lifespan: 25 to 30 years
Timber
Timber suits older Brussels houses, particularly in protected areas where the original look must be kept. It insulates well and has a warm appearance.
- Good: natural look, good insulation, repairable
- Watch for: needs repainting or re-staining every few years, and it is vulnerable to damp if neglected
- Typical lifespan: 30 years or more with regular upkeep
Timber-aluminium composite
These combine a timber interior with an aluminium exterior. They cost more, but they pair a warm look inside with weather protection outside.
- Good: durable outside, attractive inside, strong insulation
- Watch for: the highest price of the four options
Opening styles
Standard sliding. One panel slides in front of a fixed panel. It is the simplest and cheapest option.
Lift-and-slide. The handle raises the panel slightly off its seals before it slides. It handles very large, heavy panels smoothly and seals tightly when closed. It costs more but suits wide openings.
Tilt-and-slide. The panel can tilt open for ventilation or slide fully. It is useful where you want a small opening for fresh air.
Multi-panel or corner systems. These open a whole wall. They look impressive, but they need good installation and a precise opening.
Glazing: where most of the performance sits
Glass makes up most of a sliding door, so glazing choice affects comfort and bills more than almost anything else.
- Double glazing is the standard for new doors in Belgium and works well for most homes.
- Triple glazing reduces heat loss further and cuts noise, which helps on busy streets. It is heavier and costs more, so check that the frame and rollers are rated for the extra weight.
- Low-emissivity coatings reflect heat back into the room.
- Solar control glass limits overheating on south and west faces.
- Laminated glass holds together when broken and improves security and sound reduction.
Ask for the Uw value, which measures heat loss for the whole door. A lower number is better. Do not accept a quote that only quotes the glass value, because the frame matters as well.
Security features worth asking about
Sliding doors are a common entry point for burglars if they are poorly specified. Look for:
- Multipoint locking
- Anti-lift blocks that stop the panel being lifted out of its track
- Laminated glass on the ground floor
- A reinforced strike area in the frame
Some insurers offer lower premiums for certified security products, so ask yours what they require.
Installation matters as much as the product
A good door badly fitted will still leak, stick and wear out early. Look for a fitter who:
- Measures the opening on site rather than from photos
- Checks that the threshold is level
- Seals the frame to the wall properly on both sides
- Gives you a written guarantee covering both product and labour
Ask to see photos of recent Brussels installations, and if possible speak to a past customer.
Budget: what to expect
Prices depend on size, glazing and brand, so use these as rough guides and get written quotes.
- Basic PVC sliding door: from around €1,500 to €3,000
- Mid-range aluminium: around €3,000 to €6,000
- Large lift-and-slide or multi-panel systems: €6,000 and well above
- Timber and composite: usually at the upper end of these ranges
Fitting is often priced separately, so confirm what is included. Ask about removal of the old door and finishing work around the opening.
Rules to check in Brussels
Changing the size, material or colour of a door that faces the street may need a permit. Protected zones and listed buildings are stricter. In apartment buildings, you may need approval from the co-ownership for any change visible from outside. Check with your commune and read your building’s rules before ordering.
For current renovation advice and any available financial support, contact Homegrade, the regional service. Conditions change, so confirm before signing a contract.
Maintenance after installation
Even a new door needs some care. Clean the track twice a year, keep drainage slots clear and lubricate the rollers with a dry silicone product. If a fault appears later, early Click here for best Réparation Portes Coulissantes is cheaper than waiting until the problem spreads to the frame or glass.
Final thoughts
There is no single best sliding door. Aluminium suits modern homes and large openings, PVC suits tighter budgets, and timber suits older properties and protected areas. Whatever you choose, put the glazing performance, the quality of installation and the guarantee ahead of price alone. Compare at least two written quotes, check your permit and co-ownership rules, and ask plenty of questions before you commit.
