Perfect in summer, uncomfortable in winter?

In winter the sun sits lower on the horizon and its path is shorter. A room flooded with light in August may get only a few rays in January — or none at all if something stands in the way.

Real orientation should be checked room by room, not just from the main façade.

The sun's path changes with the seasons. A pool in full sun in summer can spend much of the day in shade in winter: shadows cast by the house, walls, vegetation or neighbouring buildings.

This matters especially for a second home used off-season, or a property intended for low-season rental: a sunny terrace and pool are part of the experience you offer.

Humidity does not have a single cause. Identifying its origin is the first step to understanding how significant it is.

They are not the same problem. Condensation usually comes from indoor air (water vapour, ventilation, cold surfaces). Water ingress comes from outside (roof, façade, joinery, ground).

Solutions, timelines and costs can therefore be very different. If in doubt, the opinion of a qualified professional is recommended.

Thick walls do not automatically mean good insulation. They provide thermal mass, but comfort depends on the whole building envelope.

The roof deserves particular attention: heat often escapes through the top of the house in winter and enters through it in summer. Ask whether it is insulated, how, and since when.

"Double glazing" appears in many listings. It is not enough to judge the quality of the windows: old or poorly fitted double glazing can still let air and cold through.

In Portugal, the Certificado Energético is issued by a qualified expert within the system managed by ADENE. It gives the property an energy class and may include improvement recommendations.

It is a useful document, but not an absolute measure of comfort. The same class can mean very different experiences depending on orientation, exposure, actual use of the property, equipment and surroundings. These should be studied as well.

Winters are mild outdoors, but a poorly insulated or shaded house can feel cool inside. The question is not whether there is heating, but whether it suits the house and the way you will use it.

Cooking, showers, drying laundry: daily life produces water vapour. Without adequate ventilation, it settles on cold surfaces as condensation.

Many homes in the Algarve are second homes. A house closed for months, without heating or airing, does not behave like a lived-in home.

Being close to the ocean is one of the Algarve's great assets. The marine environment can simply increase maintenance for some materials exposed to salty air. It is better to know and plan for it.

A spectacular terrace can be less pleasant than it looks if it faces the prevailing winds. The air may be calm on viewing day; that is not always the case.

Place your hand on some walls facing outside, especially to the north. A cool wall is not proof of a problem in itself. It is the combination of several signs that deserves a closer look: cold wall, condensation, smell, recent paint, traces of mould.

As the dampest rooms in the house, bathrooms often reveal the quality of the ventilation.

Especially those against outside walls. Air hardly circulates there, which is often where signs of damp appear first.

On the ground floor, the relationship between the house and the land is essential: rainwater must be able to drain away from the walls.

That is when a house shows what a sunny day does not reveal.

A house viewed on a Tuesday morning does not feel like it does on a Saturday evening. Coming back at another time shows you what changes.

A satellite map and a few mapping tools let you check a lot from home.

Some areas that are lively in summer become much quieter in winter. That can be an advantage or a drawback depending on your plans.

In an apartment, your comfort also depends on the building and your neighbours.

Asking for electricity and gas bills from the last winter months is useful. But read them with caution: they depend on how much the property was actually occupied.

A winter viewing shows the house in its most demanding conditions: low sun, rain, cool temperatures. It is the best complement to a first summer viewing.

If it is not possible, there are other ways to reduce uncertainty.