About a roof: to pitch or not to pitch

I'm seeking some general ideas here about pitched roofs versus flat roofs.

I have a (single storey) house with a flat roof, and am considering re-roofing it with a pitched roof. Not immediately, but as a long term objective (money and construction permits permitting) maybe for next time major repairs are due, which hopefully is still many years away.

Besides being easier on maintenance, and looking neater, what are the big arguments in favour or against pitched rooves? I have heard it said that the house won't get as hot in summer. Is there any truth to this?

I am considering two options. One is to just build a pitched roof on top of the existing structure. My surveyor says the structure is strong enough to support it. The other, more fancy but much more costly option is to completely remove the existing flat roof, beams and all, and then put the pitched roof on top of the bare walls, creating more spacious higher rooms and making visibility of beams and the pitch an interior feature, at least in some if not in all rooms.

Would this negate the effect of the house being cooler in summer, as I am effectively removing the air space between the rooms and the roof? Has anybody done this? What were the results?

I dont understand why you are worring about a roof that you dont intend replacing

for many years infact I am completly baffeld.

Because other stuff I'm doing before that would have to be done differently - depending on the outcome - if I don't want to rip it up and do it again later. Generally it pays to know what the step after the next is going top be while forging ahead with the more immediate.

Changing or remodeling your roof is not that easy if you do not know where to begin. You should be sure that you really wanted it so that you can choose the best type of roof for your home. You should try asking help from a professional so that they will be able to help you in fixing your roof.

Flat roofs normally have a much shorter life than a pitched roof.   Of course depending on the materials used.  

Amogles, in your situation I would probably do the same. But of course you want to have some additional benefit from the space created, perhaps create additional room(s) using dormers, or additional light with Velux windows, or a exit door to a balcony.  Well I would certainly want to do something that would be a major benefit as the work involved is substantial.

Of course it depends on your needs, your budget restraints and planning permission, but it's something you will only do once.  So I would suggest you think beyond the pitch roof to what else can be done to justify the project.

I've done it once, well in part.  The planning people did not allow me to do as much change as I wanted, part had to remain flat.  But on this portion I increased the insulation massively using Celotex and installed rooflights which was really worthwhile.  This was in UK where the intention was to create more space and improve insulation with excellent results.

I imagine in Spain it's a job you do in the late Autumn for weather reasons, but for sure a bit of planning is needed.  But for sure in Spain good insulation in the roof is vital.  One thing I did not anticipate was the effect of the insulation in terms of way that the walls and roof zoom in.  I forget the size of Celotex used, something like 6" but you have to add the roofing material, the void, the plasterboard and water barrier and it all reduces the space you are creating.   Of course technical knowledge or advice is vital, but it's an enjoyable job to do.

acer, thanks for your insights. The insulation is a good point I hadn't given enough thought to. I think my house presently has some polystyrene foam in the cavity between the roof and ceiling and the present flat roof is also painted with reflecting paint. This works quite well in the summer and so far we've managed to make do without installing air conditioning. I'm a bit worried replacing the reflecting coat by tiles would sacrifice some of the reflective nature and so lead to the house heating up more in the sun.

The present house can sometimes get unpleasantly cold in the winter though, and this despite all the windows being of modern type with double glazing. The front door is made of metal which is maybe not the wisest of choices heat-wise, and I want to replace it by a wooden one at some point. The walls are of older construction. They are 40 cm thick and made of natural stone, not brick, so not much can be done in the way of insulation short of a layer of cladding, but if the cladding was on the outside Id have moisture problems as the stone needs to breathe. If I had it on the inside I would probably lose too much space. Maybe better roof insulation might help there. It seems like a bit of a give and take game to me. 

I did also consider making the loft space usable as you suggest. This would require a steep roof pitch which would be out of keeping with the other houses in the area which all have a very shallow pitch (I'm guessing their pitch is 1:2 at the most, more like 1:3 maybe). I don't know if there are any ordinances requiring that or whether they just didn't give it any thought.  Usable attics don't seem to be much of a thing in Spain. But I guess somebody has to be the first.

Amogles, thanks for yours.  It sounds quite complex, to the point I might consider moving house.  Personally I wouldn't spend too much money without seeing at least a corresponding increase in value of the property, or at the very least an additional utility value, even if a bit self indulgent.

I had a sun terrace on my property in Spain which I never used, so I built a glass structure with an extremely well insulated flat roof, with glass around the sides completely fly screened.  It cost €5,000 or so and is questionable in terms of adding value to the property, but it's great in the winter months when it's too cold/windy to sit "outside" to read, or just enjoy the view.  The old thing about sun and glass - free heat (!) and with the structure fully fly screened I can let some, or lots out if necessary.

Obviously I don't know your property, but if it were me I'd try and decide what you want that is beneficial as otherwise from the brief outline proved I'm unsure that the project is worthwhile.  For a start wood costs an arm and a leg in Spain!

Acer, indeed, it's going to take some tough decisons. I did actually consider making a roof terrace with screens. I can catch a glimpse of the sea from my roof but it's really just a tiny fragmentary glimpse and getting smaller all the time as the trees on the properties in between keep on growing. One idea I was considering was putting a terrace in the middle of the roof while building a pitched roof on the edges. This would mean the terrace wouldn't immediately be visible from the outside and so be in keeping with the style, but overall there would still be added value.

Having said that, raising the value of the property is not my primary concern as I want to keep it long term so resale value is not really on my mind. I have already had quite a bit of work done that I believe has raised the value, so I can justify for once doing an investment that doesn't.

A glimpse of the sea!  No doubt the estage agents will expect you to pay double...that would probably be a good enough incentive for me.  But sure you have your own priorities which I understand.