wall ties

[^woody^]

You dont tooth below DPC

DPC level is the datum you work to and you gauge your new work down from this so that when you build the wall up your last course ends up level with the DPC/course on the existing house

You obviously also work to a vertical line. It may be that the new wall needs to be in a specific place and so you make do with whether it lines up to existing perp joints or not. Sometimes you can move it slightly so that it lines up better

You also work out what course will be the toothed course and set the wall out so that you start with a full brick or a half down in the footings

 

[diy001]

bearing in mind that the foundation is filled, what if it transpires on setting out that the brick work above dpc wont line up with existing wall, what should one do.

 

[stuart45]

When you tooth off an existing wall you have to follow that gauge and bring up all the walls to match that gauge.

 

[diy001]

thanks for the reply stuart, you right but
bearing in mind that the foundation is filled, what if it transpires on setting out the brickwork that once you reach above dpc the brickwork wont line up with existing wall therfore toothing wont be possible, what should one do then? keeping in mind that foundation is filled in.

 

[^woody^]

You always gauge down from a point and never gauge up. That way you are assured that by the time you have built the wall up, it is up to the correct datum/course

Typically this may involve the fist course off the foundation to be a split brick a brick on edge or a tile or some sort

 

[stuart45]

If you can't tooth it, then you will have to tie it with a wall starter kit or other ties. It will be a straight joint, but so are movement joints.

 

[diy001]

woody you're a star, you managed to understand what i was on about.
off the foundation would it be safe to minus the cut brick ect and just use extra motar bedding to bring the brickwork up to guage

 

[stuart45]

Sorry diy001, I get what you mean now. You can make the joints a bit thicker, but make sure that they are about 10mm before they come out of the ground and show. However it's usually better to split a brick or use a BOE than try and have really thick beds which tend to sink when you lay brickwork over them.

 

[diy001]

thanks stuart you with me now. may be im wrong but wouldnt a brick on edge be thinner then a stretcher how would i overcome that?

 

[stuart45]

Cut the brick in half and use the half bats so the 4 inch is across the wall. Do the same on the other skin.

 

[diy001]

do u mean soldier courses using half bats?

 

[RedHerring2]

Sorry for the interruption, just a side question on starter kits, stainless or galvanised?
I assume one chooses based on the same reasoning as render beads?
i.e. stainless used externally and galvanised used internally.
And why are galvanised painted? e.g. black?

 

[jeds]

Make yourself a gauge rod - take a length of batten or something and mark the gauge of the existing brickwork onto it. Use the gauge rod to plan out your new courses and also check your work as you go.

Personally I favour toothing in where the brickwork matches - i.e. metric to metric. But I agree it looks crap if done badly. So don't do it badly.

 

[noseall]

The one thing i will say when marrying to any wall is be prepared for said wall to be out of plumb.

This is not necessarily a problem as it may mean the wall being built "in twist" with an otherwise plumb wall at the new end. It will only likely show up on the soffit if the roofer knows his stuff.

Agree with all points regards toothing in. Either stitch drill the joints out with a 10mm sds bit or use an angle grinder.

 

[stuart45]

The old craftmen used no mortar in the toothing when blending old to new and made the new work a touch high to allow for settlement. The joints were then filled in later.