Should a new extension be tied to the to the main house?

getaroom

Apologies if this is in the wrong forum. A question arose yesterday on site. One guy says that the extension should be blocked in to the house while another says that the extension should be freestanding. Can some one advise as to which is the correct procedure?

sydthebeat

getaroom wrote: »

Apologies if this is in the wrong forum. A question arose yesterday on site. One guy says that the extension should be blocked in to the house while another says that the extension should be freestanding. Can some one advise as to which is the correct procedure?

both are wrong

Assuming its a block build.. the blockwork should started using "starter rail" systems such as this:
http://www.ancon.co.uk/products/wall-ties-and-restraint-fixings/wall-starter-systems

this allows the extension to settle independently of the existing building (which it will do anyway) without 'pulling away' from the original building. I would always specify an expansion joint here too.

BryanF

+ 1 with Syd

if no one has thought/drawn/specified the junction detail from a structural perspective, then what about cold bridging/ insulation continuity..