Rebuilding single leaf of cavity wall - wall ties

[Jimmy_shy]

I'm installing a new window in a gable end (BC approved) and have done the inner leaf; have taken down the outer leaf and now want to build back up. I know there are a variety of replacement wall ties on the market, allowing you to insert (some with resin) the tie into the existing inner leaf, and then build up the outer on the tie using standard construction. Can anyone tell me if, however, you can drill/rake out the mortar, say for 50mm in the existing wall and bed in a standard tie using a stiff mix? Sounds too easy, but then again perhaps not?

 

[noseall]

Can anyone tell me if, however, you can drill/rake out the mortar, say for 50mm in the existing wall and bed in a standard tie using a stiff mix? Sounds too easy, but then again perhaps not?

....er,.....no. it will not have the same effect as a built-in tie .

if you were to pull hard on a tie wire retro-fitted this way, you would pull it out along with the plug of mortar. a built-in tie wire has the benefit of the inherent strength of a larger body of surrounding mortar locking it in.

 

[Jimmy_shy]

Thanks. Any tips about the best sort of ties to use in this context please?

 

[noseall]

these.http://products.ihs.com/cis/Doc.aspx?AuthCode=&DocNum=99205

 

[noseall]

here's another link.http://www.bluebird-fixings.ltd.uk/cavity.htm

 

[^woody^]

If the blocks are the aerated type, you can use helical ties knocked in like nails.

Otherwise you will have to use something like 'L' shaped fish-tails screwed and pluged to the internal leaf.

I am curious why you took down all the wall to form a window. Could you not have just cut the opening, or at least left part of the blockwork up and this would not cause a problem with ties and rebuilding?

 

[Jimmy_shy]

I took down the inner leaf to sill level as I was fitting a steel in that wall as well, and the block/brick was ribby. I had intended to cut the outer leaf, but carried on down from lintel level from inside when the brick courses came away. Thanks for the advice!

 

[Jimmy_shy]

thanks for the links Noseall!