Replacing roof on old house

[Pintor]

Hi
I'm in the process of getting my roof replaced - old stone cottage in central algarve.
I've had a couple of builders look at it and one has suggested new eucalyptus beams plus canes plus insulation then new tiles.
The other has said new beams then a concrete roof system on top - this worries me a bit as won't we need to factor the extra load on the old stone walls?
Also does anyone have any experience on what price I should be prepared to pay? It's approx 60m2.
Thanks all

[canoeman]

If a wooden roof make sure everything treated, that you'll see, have it close boarded decorations all done then.

Concrete roof reguires a concrete ring beam to disperse weight evenly, you can incorporate insulation and reduce load by using purpose made polystyrene infill rather than clay/cement blocks, rather than just the normal insulation laid between concrete roof and tiles. Beams would be concrete not wood.

If you want a long term solution and can afford it I'd opt for concrete, if your considering solar incorporate tubes to feed pipes through so there in place.
Prices can't help Algarve has a different pricing structure to rest of Portugal

[MrBife]

You need to do a survey before deciding as it is unlikely that an older building has anything much in the way of footings/foundations. If in doubt bring in a proper surveyor to get fully independent advice.

If you suddenly change the load on the existing walls on an older house then you could certainly create some problems.

Ideally the weight of a new concrete roof should be taken by new concrete pillars and as Canoeman suggests a concrete ring beam.

As a guide I am just in the process of doing this job myself and the concrete roof element alone together with columns and ring beam has cost me €60k for a 275 m2 house. That includes 8cm EPS insulation and the most expensive (non porous ) roof tiles.

Algarve construction can be more expensive if you are not careful but there are plenty of good constructors around at the moment that just want to keep themselves in work and are prepared to price close to cost price to do that. In my view its a great time to get any building projects done.

[Verinia]

We are in the South..Algarve and have an old cottage as you describe and had the roof replaced about five years ago. The beams are sweet chestnut, which apparently are much more resistant to termites. Then wooden planks to make the ceiling. I have stayed in a house with canes, but we found that over time they let the dust in from the roof. Between the boards and the tiles there is an insultation layer, then old terracotta tiles which are a mixture of old salvaged ones on the outside to keep the character and new on the inside. There are no foundations in the house...just stones bound together by mud and I am sure it would fall down in an earthquake. There was talk of a concrete roof, when we did this because of the fire risk, but the builder did feel it was better done the traditional way.

Good luck with it. I must say our roof looks wonderful and adds a lot of charm to the house...but it is a bit noisy in a hard rainstorm!

[Pintor]

Thanks for all the feedback, as ever very useful.

I think the concrete idea may be a bit weighty on our old walls. One builder has suggested the traditional route like yours Verinia, which does sit more comfortably with me. Good to hear your advise re canes too as much as I like the look I have been warned about the dust problems. We have canes at the moment and the dust is quite bad.

Thanks again!