No, no, no – this could be as far from the truth as pigs may fly. There is nothing energy efficient about cathedral ceilings quite the contrary.
What are the advantages of cathedral ceilings, apart from looking good to the beholder or cheaper to build for the builder there are no other advantages with a cathedral ceiling.
WHEREAS THE DISADVANTAGES ARE MANY AND COSTLY
Number one is the higher the ceilings the higher the energy costs – for a start you are heating and/or cooling a larger volume of area which is usually taken up by roofspace. A roofspace is usually there to keep the outside contact from the elements at a distance, much the same as a cavity brick wall of 50mil between the outside brickwork from the plaster board. With a cathedral ceiling you don’t have this protection so needless to say no matter what type of insulation they come up with its really not going to make that much difference. Without a roofspace there is no cavity to ventilate and any type of natural ventilation is of no use. So you see you are totally bound to use mechanical energy for the cooling and heating of a home with cathedral ceilings.
You can open all your windows when a hot summers day has cooled down in the evening, however the heat still sits in the area where the roofspace would have been much similar to the inversion layer does and the only thing that will seem to cool you down is energy using mechanical power.
Then there is the further problem of condensation, if you have a condensation problem with cathedral ceilings these are almost impossible to alleviate.
Pros – may look good to the beholder will save the builder a lot of money.
Cons – Will be impossible to cool down by natural means. Will cost much more in energy costs both summer and winter. Could have condensation problems that would be very hard to harness.
I would highly recommend against cathedral ceilings due to the inherent problems.
In summer we get so many people who want to use our ventilation systems who have cathedral ceilings, when we tell them that our systems won’t work for them and there is nothing natural that will work for them, they get quite upset.
However, as a roofer with 50 years’ experience I have seen all the problems that happen with roofs and it has been enough for me to not personally build or recommend using cathedral ceilings and/or flat or low pitched roofs.
However if you have a ceiling space and need effective ceiling space ventilation
Universal Tile Ventialtors have the best roof ventilation systems in the world.