could roof leak during snow be 'normal'

Our kitchen extension is 2 years old and has a pitched tiled roof.

During the severe weather before Christmas, a water stain appeared on the inside wall, running from the ceiling right down to the skirting, obviously a leak from outside.

I rang the builder who built it two years ago and someone is coming round for a look on Saturday, but his first reaction was that "snow and sleet is completely different to rain" and "it can work it's way into all sorts of places" and "it's probably nothing to worry about but we'll check it to be sure". I've a feeling this will be the line on Saturday and they will advise me not to worry and just paint over the stain.

Is this a fob off or has he a point? What action should I reasonably expect from them?

It's a reputable firm, with Homebond, a nice website etc.

Happened here too.

Leak as your after snow started to thaw.

Nothing since so we're taking it that it just worked its way in some way.

.... 'til next time.

So you builder may not be too far off the mark ... give him the benefit of the doubt .... then see what you'll do.

in the first snow earlier last year we got a small leak above the velux. basically what happened is that the snow formed into a small drift, or build up, and as it thawed obviously at the top first it formed a puddle above the flashing which allowed a small amount of water to come in. this year i just brushed the snow away before the thaw and there was no repeat.
you may have gotten a build up something similar at your gutter

Snow stops water running off the roof the way it should. So it may form puddles and then, go/flow the wrong way. For example it might backfill up over the top of the tile and onto the felt below. Which might find a gap that wasn't tested before, when rain water flowed normally off the roof.

Besides that all the severe cold and freezing can destroy pointing and brickwork if water gets in and freezes. Once it thaws you then have a problem.

Had similar problem. In my case it was down to the roof staying frozen for so long that as some damp warm air escaped through the recessed lights the moisture froze on the membrane. When the thaw came quickly it melted and ran down the back of teh foil backed insulation to where the insulation slabs joined and showed as a damp spot on the ceiling.