Extension: Thermalite block vs timber frame

[Wingmeister]

Hi everyone,

I've been a long term reader of DIYnot but have today registered and I'm really after some help / advice on my Project for 2010. I live in a detached 4 bedroom house in the fens. Brick and block on a piled foundation, built in 2001. Trouble is that the upstairs rooms are really quite small. We have a single story study and 1.5 garage attached to the main house and I'd like to build above (large bedroom with ensuite). I have checked with the structural engineer who has done preliminary calculations to determine if the piles and beams are capable of holding another storey and he has advised they are provided it is constructed of a timber frame. My problem is cost really. I'm planning on doing much of the work myself and I'm wondering what the weight difference would be between Thermalite blocks or timber frame and anybodies opinions on which would be cheapest /easiest to build and then heat / maintain for the future. The majority on the extension would be above an unheated garage. I'm also unsure of external dressing of a timber frame building, I was thinking of a light coloured render. The bricks are Kimbolton Red Multis currently.
Any thoughts / help would be greatly appreciated.

Thanks.

 

[The-brickie]

Surely if you S/E has spec'd timber frame then thats what it should be? You can (should, I've not seen it so just second guessing) run brickwork up the outside to match existing.

Timber frame can be one of the best methods of building for a highly insulated build. There is a vast amount of technical stuff on the web sites of the insulation makers.. Celotex, Kingspan etc..

 

[Wingmeister]

Thanks for the reply. The engineer has advised that we'll not be able to brick up the external walls because this would overload the foundations, it would have to be rendered or similar (as this is lighter he said). I started looking into SIPs panels and these look pretty straightforward to get a basic weathertight frame up. The rest I could do myself over a long period. People seem to have mixed opinions on timber frame, but the more googling I do, the more it seems accepted nowadays.

Thanks.