home_off = new Image();
home_off.src = "img/nav-home.gif";
home_on = new Image();
home_on.src = "img/nav-home-on.gif";

about_off = new Image();
about_off.src = "img/nav-about.gif";
about_on = new Image();
about_on.src = "img/nav-about-on.gif";

preservation_off = new Image();
preservation_off.src = "img/nav-pile-preservation.gif";
preservation_on = new Image();
preservation_on.src = "img/nav-pile-preservation-on.gif";

rehab_off = new Image();
rehab_off.src = "img/nav-pile-rehabilitation.gif";
rehab_on = new Image();
rehab_on.src = "img/nav-pile-rehabilitation-on.gif";

pilespecifications_off = new Image();
pilespecifications_off.src = "img/nav-pile-specifications.gif";
pilespecifications_on = new Image();
pilespecifications_on.src = "img/nav-pile-specifications-on.gif";

corrosion_off = new Image();
corrosion_off.src = "img/nav-corrosion-prevention.gif";
corrosion_on = new Image();
corrosion_on.src = "img/nav-corrosion-prevention-on.gif";

quote_off = new Image();
quote_off.src = "img/nav-quote.gif";
quote_on = new Image();
quote_on.src = "img/nav-quote-on.gif";

casestudies_off = new Image();
casestudies_off.src = "img/nav-case-studies.gif";
casestudies_on = new Image();
casestudies_on.src = "img/nav-case-studies-on.gif";

function navChange(button,mode) {
	document[button].src = eval(button + "_" + mode + ".src");
}