Our appellant, James A. Thomas, was an apprentice plumber engaged by a subcontractor in connection with the construction of a dwelling for appellee Schwab. The carpentry work was under subcontract to another subcontractor, and this work included the installation of the windows. In going from the inside of the partially completed building to the roof to install a vent pipe, Thomas went through a window, holding on to the casement of the window to steady himself. This casement had been temporarily secured in place by the carpenters, and its installation was not complete. The carpentry subcontractors were actively engaged that day in the performance of the carpentry work on the building. The casement gave way in Thomas’s hand, and he lost his balance, fell first to the roof and then to the ground, and was injured. The foregoing facts were shown by the pleadings and attached affidavits.

Upon an oral hearing the District Court ascertained that there was no genuine issue as to any material fact. Upon the basis of the undisputed facts it entered summary judgment for the defendant Schwab. We think its judgment was correct. On the undisputed facts the carpenters were not negligent. Accordingly we do not reach the question whether appellee would have been liable to appellant if negligence of the carpenters had caused a dangerous condition.

Affirmed.