Per the Talstar P product label
for pre construction you would use 1 oz per gallon of water per 10 square feet, but Talstar is not the best product to use for this. Termidor SC is the #1 termite product on the market. When used as an in-ground barrier treatment, Termidor SC will protect your home or business for over 10 years. Termidor SC
is completely undetectable by termites and once termites touch it they contact, ingest and spread the termiticide until it eliminates the entire colony. Termidor SC controls all types of termites including subterranean, formosan, and drywood termites. Talstar P lasts for about 5 years in the ground and works as a repellent, killing only those insects that come into contact with the treated area.