Wall tie size/type

[trevorbayliss]

I need a bit of help on which wall tie to use for my new extension which will be brick and block.

I want to fit 100mm solid insulation as well for better insulation purposes, so by wall is going to be 350mm wide. The cavity will be a50mm gap not including the 100mm insulation.

I was thinking about a 275mm tie such as this:

http://www.ebay.co.uk/itm/Ancon-Sta...442921?hash=item2345d501e9:g:64wAAOxyNThTddCF

Have i got the correct size and are these ties ok?

 

[tomfe]

If you are building this yourself I would use a full fill insulation:
100mm Kooltherm 0.18u with brick outer low density concrete inner.
150mm DriTherm 32 0.18u, 34 0.19, 37 0.21

 

[trevorbayliss]

Is the full fill the soft insulation ? Why would that be a better bet ?

I want to use a strong block for the inner as resting big oak purlins on there to support the flat roof construction. Is the low density block the higher newton one then ?

 

[tomfe]

Yes, the cavity batts are easy to install also cheaper, unless you need a clear cavity due to location it's the way I would go.
You can get pretty much any block in 3 or 7 n, I would not use an acc block but a light wight block like a fibolite.