Ruairi

No problem, also keep an eye out for thermal bridges (elements that bridge the insulation layer and conduct heat faster). These can have quite a big effect on the performance of your building. They should ideally be designed out so the construction is thermal bridge free, but this is quite difficult to achieve in practise.

No problem, always happy to give some advice if I can. Depending how far along you are with the production of tender/construction drawings I would consider changing your Architect if your not happy with them. It will be difficult to achieve what you want otherwise, as the devil really is in the detail with these things. Regarding insulation, a U-value is the measure of how fast heat flows through a component and the lower the number the better insulated that component is, (measured in watts/meter squared Kelvin). I am not sure what u-values you are achieving with your project, but as a rough guide for PH you would be looking at Walls and floors 0.15 W/m2K Roofs 0.10 WW/m2K Triple glazed windows and doors 0.8 W/m2K I would be aiming for this on most projects to start with. Regarding the other items it is hard to give you much advise as things like the selection of a heating systems and renewable is very project specific and there is no one size fits all. Hope this is some help Ruairi

Hi Try googling Passivhaus. Its a German low energy standard that is gaining popularity in the UK and Ireland eco movement. The basic principle in a nut shell is to invest in insulation (more than what you suggest for your project) and airtight construction in conjunction with a heat recovery ventilation system. Then you?re left with a tiny space heating demand which does not require a conventional heating system, though you can have one if you want. Solar thermal is probably a good idea too, my parents in Ireland get most of their hot water from March-October from theirs. You can still have your bolt on renewables if you like, but not necessary, better off investing insulation. If your interested in Passivhaus ask your Architect (not to be confused with passive solar) he should have heard of it atleast. There is a whole certification process for QA, but it?s unlikely you will achieve this if the building has not been designed to meet the standard from the outset. You can still apply the principles though. Ruairi (Architect specialising in Low energy Design)