Ask a Tradesman
How much approx should I be looking at to get my wall ties done, its a 1930's semi detached? THANKS
Over time mortar joints, which host the wall ties, undergo a chemical change through carbonation. The mortar becomes aggressive to the base steel and its protective coatings, reducing the life expectancy of cavity tie systems to as little as 26 years. The design life of the building is typically much longer than this period and it therefore follows that at some point the installation of a wall tie replacement system may be necessary if the stability and load sharing capacity of the wall is to be maintained.
As wall tie corrosion sets in the steel wall ties generate a build up of iron oxide layers which occupy a greater volume than that of non-corroded steel. In most cases, particularly when wire wall ties have been used, the increase in volume is accommodated within the mortar bed as the cavity ties erode. In such cases there may be little sign that the outer facade is free-standing and the walls not supported, save that the wall may appear bulged.
In other cases, particularly where sheet steel or vertical twist wall ties have been used in less forgiving mortars, replacement of sound steel with iron oxide build up may have the effect of lifting the masonry above a line of insitu masonry ties. If expansion is widespread along several rows of the corroding wall ties, a tell-tale pattern of horizontal cracks may be produced along each wall tie course.
The avg cost should be around £50 a sqm to carry this out.
Answered 19th May 2011
it depends on so many aspects.
I would advise to get 3 quotes from reputable specialists from somewhere like the yellow pages. They will be happy to attend and give you the quotes as long as you don't let them know you just require a price rather than them having a prospect of securing the work.
This ask a tradesman isn't the best forum to receive an exact price but if you require the work done your three quotes will stand you in good stead to return here and find a better or equal costing for the work.
Answered 14th May 2011
No one can give you a price without looking at the job, and the information you have supplied.
There are several different methods that can be used.
Normally a structural engineer would be involved to specify the system and order of works, he should then give you an approximate cost.
The firms specialising in this may have there own advisors, so best to contact them where you will get better advice.
Answered 15th May 2011
you should check you actually have a cavity before you worry about wall ties, in my experience most 1930's semi's would be solid 9" Brick construction. No cavity no wall ties.!
Answered 22nd May 2011