Material Selection..

Spent some more time contemplating what I'm going to be doing downstairs, the two options I had were these (Yes, I've been having fun drawing on the pc!)

Plasterboard with insulation and damp proof membrane, the wood alone was going to be €1300,-

AAC (Aerated Autoenclaved Concrete) bricks, which is what I'm hoping to settle for.

It will offer a more solid build long term, and does away with the insulation which might end up having damp problems, as well as potential vermin, plus its extremely easy to work with.

I've been doing some calculations to compare both materials, using values obtained via the interweb, which might not be accurate at all, but still give a rough impression.

Situation one, Plasterboard.

Thermal Conductivity (K) mm Thermal Resistance (R) Plasterboard 0.16 W/mK 12.5 0.078125 M² K/W Mineral Wool 0.03 W/mK 50 1.666667 M² K/W Air 0.024 W/mK 20 0.833333 M² K/W Mortar/Concrete Wall 1.3 W/mK 400 0.307692 M² K/W Polystyrene 0.03 W/mK 50 1.666667 M² K/W Total: 4.552484 M² K/W Thermal Transmittance (U) 0.21966 W/M²K

Situation Two, AAC:

	Thermal Conductivity (K)		mm	Thermal Resistance (R)
AAC	0.15	W/mK	50	0.333333	M² K/W
Air	0.024	W/mK	50	2.083333	M² K/W
Mortar/Concrete Wall	1.3	W/mK	400	0.307692	M² K/W
Polystyrene	0.03	W/mK	50	1.666667	M² K/W
				4.391026	M² K/W
	Thermal Transmittance (U)			0.227737	W/M²K

I think those values are very acceptable for an old building's walls, especially if you compare it against total price.

Oh yes, the polystyrene is for the outside wall, sometime during the summer.