MochaFiona

My husband and I have been looking to buy a house in Portugal. We have noticed signs of mould / mildew on the external walls of buildings. Is that a sign of poor construction or just cosmetic? Attached are a couple of photos to illustrate:


Many thanks in advance !

scrubbedexpat142

Salts leaching from the blocks / mortar? Maybe?

How old is the house?

MochaFiona

The red one was built in year 2000. Don't about the beige one (it was an old listing that's no longer there).

macliam

It depends where these houses are.... but there are several possible answers. Firstly, however, note that the pattern of the discolouration follows the lines of the reinforced concrete structure and the block infill - different materials, different qualities. It does suggest that there isn't any great depth to the render used, but again this can be better than too much..... Then -

a) It can be simply a case of false economy in painting with poor quality paint or insufficient coats..... paint is expensive and new paint appears to cover well, but issues will soon show after a year or two. If the house has been on the market a while, it's doubtful that the vendors will feel like spending out to repaint.....

b) It can be "salitre", literally saltpeter, but the common Portuguese term for any efflorescence caused by minerals leaching out of the building materials. This isn't necessarily a sign of bad quality - all cenment and mortar needs water and much water contains minerals. In my area the water is very ferrous - so ceramics become stained even after filtration. Look for telltale signs of bubbling or white crystalline efflorescence on the surface.

c) It can be the effects of high humidity - I've noticed this a lot on the Alentejo litoral, where the air gets very damp over the winter months. This appears to be an issue with coastal areas...... so beware buying on the evidence of a summer viewing.

Have a word with locals...... they'll tell you whether anything you see is exceptional - and always consider that what you are seeing could easily have been disguised by a coat of fresh paint had the vendors wanted to trick you.....

liveaboard

All the houses around me look that way at certain points of weather change.
The hollow bricks heat up and cool down faster than the solid concrete parts. So when condensation forms on the building, one part looks different to the other.
When it's dry, the patterns disappear.

If you DON'T see the pillars and ring beams (clear in the top picture), then there's something to worry about.

wellinever

looks like simple dampness to me, due to simple damp air in the shade.
Probably down to needing a proper paint job, blasting first, then using good quality (and expensive) paints.
Built in 2000 will probably not have much (if any) in the way of insulation or water membrane.
But should be a cavity wall (maybe some old expanded polystyrene board).
All depends on the original owner and builder, always quality vs cost.
One of the issues of the way building is done in PT, buy plot, design house, find builder, so each house is individual.

Alan PT

I definitely wouldn't dismiss a place based on the outside, it says more about the local microclimate and how recently it was painted than anything else.

But train your eyes (and nose) to spot the signs on the inside. You'll probably find some (unless it's a very new place) but the extent can give you a clue whether there's a bigger problem than just the usual "it's a Portuguese house"

MochaFiona

Many thanks to everyone for your replies. They are all very helpful! Additional comments and opinions are welcome :-)

coleio

Shirly you'd just get a "building" survey before any serious intention which would give you any relevant info to base your decision on rather then asking on some interwebs forum where "everyone" is a charted building surveyor offering free professional advice based on not seeing the property.

MochaFiona

I agree that a"building" survey is a good idea before buying any property. However, we are doing our search on the internet first and we have become "very good" at vetting properties from the info and photos provided, including finding the actual houses using Street View (even if the ads do not disclose the exact location). Asking this question here allow us to know if we should eliminate houses that have this kind of pattern.

Alan PT

In the UK, less than 15% of people get a "Building Survey", which is the only thing really worth being called a survey

Portugal appears to be different, but it's not really, it just doesn't have the same industry of money-making semi-trained people