Whenever a judgment or decree is rendered on an instrument waiving the homestead or upon a demand against which the homestead cannot be claimed the court shall include in its judgment or decree words to the following effect, as the case may be: “Upon an instrument waiving the homestead,” or “upon a claim against which the homestead cannot be demanded.” This statement shall be endorsed upon the executions issued upon such judgments or decrees. In any action or suit when it is not apparent from the face of the pleadings that the demand is not subject to the homestead exemption the plaintiff shall not have the benefit of the foregoing provision of this section unless in his declaration he alleges that his demand is not subject to such homestead exemption. But no presumption of nonwaiver or that the judgment or decree was rendered upon a demand against which homestead could be claimed is to be drawn from the silence of any judgment, execution or decree on the matters provided for by this section.