Touloumes v. E.S.C., Inc. - Pennsylvania Supreme Court - June 19, 2006
http://www.courts.state.pa.us/OpPosting/Supreme/out/J-183-2004mo.pdf
The court held (5-1) that Pa. R.C.P. 238 does not apply to a contract action seeking to recover damages for injury to property.
The dissent (Newman, J.) http://www.courts.state.pa.us/OpPosting/Supreme/out/J-183-2004do.pdf said that all of the elements of the rule are present, that the rule is "clear and free from all ambiguity" and should apply. The "Majority's exploration of the intent of the Rule was not required because the Rule itself explicity provides that Appellants are entitled to delay damages.
The text of the rule is at http://www.pacode.com/secure/data/231/chapter200/s238.html