In this work, a numerical simulation model is proposed with the purpose of determining the minimum and maximum measuring time for the hot wire parallel technique. An alternative experimental arrangement is also proposed for materials with thermal conductivity higher than 15W/mk. In this case, the experimental thermal transient is detected very close to surface of the hot wire, and it will be called hot wire surface technique. When using this arrangement, the time interval considered for the calculations may be several times bigger than that one corresponding to the parallel technique. Experimental results obtained with the surface technique are also checked against those ones obtained with the parallel technique.