Thermal Insulation in the Algarve
People often assume insulation is unnecessary in the Algarve because it does not get cold. In practice insulation mostly solves summer, and that is where the difference shows every day.
In the Algarve the problem is heat, not cold
An uninsulated wall heats up in the sun during the day and releases that heat inwards at night. It is why so many older Algarve houses are still warm at two in the morning, even with the windows open.
Insulation delays and reduces that transfer. In practice it means a house that needs less air conditioning to reach the same temperature, and that holds it for more hours.
ETICS: insulating from the outside
The ETICS system fixes insulation boards over the existing wall, covered with mesh, reinforced render and a finish coat. It is the method we use on most refurbishments.
Insulating externally has two advantages over internal insulation: it does not eat into floor area, and it eliminates thermal bridges at slabs and columns, which is where heat gets in even when the walls themselves are treated. The trade-off is that it changes the facade, which needs care in areas with their own planning rules.
When it is worth doing
The economically obvious moment is when the facade is being worked on anyway. If the house needs failed render hacked off and repainting, the extra cost of insulating is a fraction of the total, because scaffolding, preparation and labour are already in the budget.
Insulating on its own, with a facade in good condition, takes longer to pay back. It still makes sense in houses where air conditioning runs many hours a day.
Does insulation really cut the electricity bill?
It cuts cooling consumption, which is the largest share in a house with air conditioning. The actual saving depends on the starting condition, solar orientation and how the house is used, so be wary of anyone guaranteeing an exact percentage before seeing it.
Can I insulate only the most exposed facade?
You can, and it is sometimes the right call on a limited budget: the west-facing facade usually takes the worst of it in the Algarve. The result is partial but measurable, and it concentrates the spend where the gain is largest.
Does insulation fix damp problems?
It helps with interior condensation, because it keeps walls warmer. It does not fix rising damp from the ground or leaks through the roof, which have different causes and must be dealt with before insulating, or they end up sealed underneath the system.