12 Was it foreseeable that the plaintiff might ascend to the new first floor and hence be exposed to the danger of stepping into the unprotected cavity over the stairwell? I am not persuaded that it was foreseeable by Laver, or if foreseeable, that Laver was in breach of any duty to the plaintiff to guard against the risk that the plaintiff might suffer injury. It is not clear whether the tarpaulins supplied by Laver were sufficient, no matter how erected, to cover the area that needed to be covered or whether the way in which Maveric erected them, one substantially overlapping the other, resulted in most of the garage being exposed to the elements. Maveric was the sub-contractor in daily occupation of the premises, whereas Laver's supervisor, Mr Hoffman, only visited periodically and then only to co-ordinate the building works. Even before the evening of 10 March when it rained so heavily, it was, in my view, foreseeable by Maveric that one of the plaintiff's household might have occasion to go on to the new upper floor and inspect the work done to date. In these circumstances, there was already a risk that such a visitor might be injured by stepping into the cavity if he were not warned of its existence, or if the simple and inexpensive precaution of nailing boards over, or erecting a barricade around, the cavity were not taken. Whether that be so or not, however, when Mr Eric Verdouw, the second named defendant's foreman, so concerned at the heaviness of the rain that he drove around to the site to ensure that the canvas was still on the roof as he had left it, came to the premises, it must have been abundantly obvious to him that the figure in the garden wearing a yellow raincoat was the plaintiff or a member of his household and that he was also concerned about the risk of water damage and hence might venture on to the roof to check the adequacy of the cover and possibly to improve upon it. In those circumstances, there was, in my view, a clear duty upon him to alight from the car and either to reassure the plaintiff that no action on his part was warranted or to warn the plaintiff that if he insisted upon going on to the first floor at night with only a torch to illuminate the scene, there was a danger in the form of the unprotected stairwell. In my opinion, Maveric's foreman was negligent in failing to adopt either course and as a result of that negligence, the plaintiff sustained his injuries. The first named defendant is vicariously liable for the negligence of the second named defendant and in consequence the plaintiff is entitled to judgment against both; but notices of contribution having been exchanged by both defendants, I find that having regard to the extent of Maveric's responsibility for the damage, it is just and equitable that it bear the whole responsibility therefor.