There is a sentence we hear constantly in our shops: "I have a fireplace, but the house is still cold." It is not your imagination — it is physics. An open fireplace loses most of its heat up the chimney, and on top of that it pulls already-warmed air out of the room to feed the fire. It is beautiful, it is atmospheric, and it is a terrible way to heat a house. This guide explains what to do about it.
Why Algarve winters catch people out
Anyone arriving in the Algarve expecting a mild climate gets the same surprise in their first winter. The days are gentle and sunny, but the nights turn cold and the humidity rises. And houses here were built with the opposite priority to northern Europe: keeping heat out. Thick walls, tiled floors, minimal insulation, and often a house that stands empty part of the year and chills to the bone.
The result is a damp cold that a portable electric heater does not solve — it warms the air briefly, but does not warm the fabric of the house or bring the humidity down.
Fireplace insert: what changes
An insert is a closed appliance with a glass door, fitted inside the existing fireplace. That apparently simple change alters everything: combustion becomes controlled, the air supply is regulated, and instead of going up the chimney the heat is transferred into the room — by radiation through the glass and by convection through the body of the appliance.
In practice, an open fireplace that barely warmed the living room frequently becomes the main heat source for the house. And it uses considerably less wood to do it, because it extracts far more from each log.
There are two families of solution, depending on what you already have:
- Insert — fits into an existing fireplace. The natural route if you already have an open fire and want to use the structure and the finish.
- Log burner (freestanding stove) — a standalone appliance that needs no existing fireplace, only a flue outlet. The route if you have no fireplace at all.
The choice between the two is covered in detail in our article on a log burner or a fireplace insert.
The chimney matters more than the appliance
If there is one idea to take from this article, it is this one. The overwhelming majority of problems with wood-burning appliances — poor draw, smoke coming into the room, blackened glass, tar — are not appliance problems. They are chimney problems.
And there is a specific reason this is common in the Algarve: many houses have chimneys built for an open fire. An open-fire chimney is wide, often irregular inside, and was designed for a completely different flue gas flow. Connecting a modern closed appliance to it, with nothing else changed, is a recipe for exactly the symptoms above.
The solution is to line it: install a stainless steel flue of the correct section for the appliance, running through the existing chimney. This normalises the draw, heats up faster (which reduces condensation and tar) and is also a safety matter — a badly installed closed appliance is a carbon monoxide risk, not merely a poor performer.
When we assess a property, we always check the chimney before talking about models. And if it is not suitable, we say so before the purchase, not after.
Firewood in the Algarve: availability and consumption
Firewood is relatively cheap and local — eucalyptus, olive and holm oak are all common in the region. The critical point is not the price but the seasoning: green or badly stored wood holds a lot of water, gives little heat, dirties the glass and tars the flue. Well-seasoned wood, kept out of the rain with air circulating, gives more heat and fewer problems.
If you would rather not handle logs, there is the pellet alternative: a pellet appliance feeds itself from a hopper, is thermostatically controlled and can be programmed to start before the house wakes up. It costs a little more per unit of heat, but it is incomparably more convenient — especially for anyone who is not in the house all year.
The finish: where the look is won or lost
A well-installed insert disappears into the wall as though it had always been there. A badly installed one shows forever. The finish — surround, stone or plaster cladding, log niche — is what separates the two, and it is a part of the job we treat with the same care as the technical side.
In short
If you have an open fireplace and a cold house, a fireplace insert is almost always the intervention with the biggest impact and the best value. But choose someone who checks the chimney first, and the model second.
Want your fireplace assessed? Visky looks at the space, checks the chimney and presents a quote within 24 working hours, with no obligation. We have shops in Lagos, Almancil and Aljezur where you can see appliances in person. Get in touch.
