Calha vs. algeroz vs. caleira
While calha, algeroz, and caleira all relate to systems for draining rainwater from roofs, their usage depends heavily on the region. Calha is the standard term in Brazil for the horizontal channel. In Portugal, usage is more complex: calha and caleira are often used for the horizontal section, while algeroz technically refers to the vertical downpipe or spout, though these terms are frequently swapped in casual European Portuguese conversation.
Calha
B2This is the most universal term, understood in all Portuguese-speaking countries. It refers to the U-shaped channel (usually metal or PVC) fixed to the edge of the roof to catch rain. In Brazil, this is practically the only word used for this object. In Portugal, it is also very common.
A calha está entupida com folhas secas e precisa de limpeza.
(The gutter is clogged with dry leaves and needs cleaning.)
Vou contratar alguém para instalar uma calha nova na varanda.
(I am going to hire someone to install a new gutter on the balcony.)
A chuva transbordou da calha durante a tempestade.
(The rain overflowed from the gutter during the storm.)
Ele pintou a calha de branco para combinar com a casa.
(He painted the gutter white to match the house.)
Algeroz
C1This word is exclusively used in Portugal and is of Arabic origin. Technically, algeroz refers to the vertical downpipe that carries water from the roof to the ground or the spout that throws water away from the wall. However, in casual European Portuguese, people often use it to refer to the entire gutter system. It is widely unknown in Brazil.
A água desce pelo algeroz e vai para o esgoto da rua.
(The water goes down the downpipe and into the street sewer.)
O algeroz rebentou e está a molhar a parede toda.
(The downpipe burst and is wetting the entire wall.)
Ouvia-se o barulho da água a cair no algeroz.
(You could hear the sound of the water falling in the downpipe.)
Temos de substituir o algeroz que enferrujou.
(We have to replace the downpipe that has rusted.)
Caleira
C1Primarily used in Portugal, this word is often interchangeable with calha. However, caleira can specifically imply a built-in channel made of masonry or stone, rather than a separate metal attachment, though it is used for both. In Brazil, it is rare in this context and usually refers to agricultural irrigation channels or street gutters.
Os pardais fizeram um ninho na caleira do telhado.
(The sparrows built a nest in the roof gutter.)
Esta casa antiga ainda tem uma caleira de pedra.
(This old house still has a stone gutter.)
Devemos impermeabilizar a caleira para evitar infiltrações.
(We must waterproof the gutter to prevent leaks.)
A caleira precisa de ser reparada antes do inverno.
(The gutter needs to be repaired before winter.)
Summary
In summary, if you are in Brazil, always use calha. If you are in Portugal, calha and caleira usually refer to the horizontal collecting channel, while algeroz refers to the vertical pipe or spout that drains the water down, though Portuguese speakers often use algeroz and caleira interchangeably for the whole system.