Open vaulted roofs for house extensions - are there any drawbacks?

Forming an open vaulted roof or ceiling line within a house extension is relative easy and straight forward for mono-pitched roofs. Flat roofs and fully hipped apex roofs are more difficult. Many single storey extensions have ‘lean to’ pitched roofs attached to the existing walls as the new rafters for the house extension are simply supported at the top and bottom and do not require ceiling joists for lateral supports to the walls.

Therefore removing the horizontal flat ceiling joists for a traditional or matching ceiling line within the house extension will create a open vaulted ceiling line. Many refer to these ceilings as ‘scaling ceilings’ to reflect the varying ceiling heights over different areas of the extension.

The effect of open vaulted ceilings within a house extension is to increase the sense of space so even a small lean to rear extension of only 2M could fee double the size with an open vaulted ceiling line.

The only down side to this roof design for a house extension is that all heat rises so the open vaulted room will be more expensive to heat compared to a tradition 2.4M floor to ceiling height. Roof fans could be used to push and circulate the warm air for greater heating efficiency.