Hi Inmedia

You could use something like that for selecting home node:

  <xsl:variable name="frontPage" select="$currentPage/ancestor-or-self::*[parent::root]" />

or 

<xsl:variable name="frontPage" select="$currentPage/ancestor-or-self::*[@isDoc and @nodeType = '1049']" />

where 1049 - is nodeType of homeNode

Provided that your homepage has the doctype 'Frontpage', you could do this:

<xsl:template match="/">
  <xsl:apply-templates select="$currentPage" mode="banner"/>
</xsl:template>

<xsl:template match="*" mode="banner">
  <div class="container banner" style="background-image: url({bannerImage})">
    <!--If no banner image is selected on the current page, pull the value from the homepage node-->
    <xsl:if test="not(normalize-space(bannerImage))">
      <xsl:attribute name="style">background-image: url(<xsl:value-of select="ancestor-or-self::Frontpage/bannerImage"/>)</xsl:attribute>
    </xsl:if>
    <div class="pagename">
       <h1><xsl:value-of select="overskrift" disable-output-escaping="yes"/></h1>
     </div>
  </div>
</xsl:template>

is working on a reply...