Going to use hammer fixings to build a sound barrier on a party wall in a semi which will be topped off with sound panels. Will be mounting a TV on it. How deep should the wood batten fixings go into the wall ? I am thinking about 2 inches should cut it but not sure. Am also thinking of using some grab adhesive in the fixing holes but perhaps abit OTT ? Last thing I want is the wall to fall off. Substrate is block.