Sarah Beeny meets recently engaged couple Mark and Gudren whose Warwick home is crumbling to dustMark and Gudren's Victorian terrace is constructed from an early, experimental concrete mix. The walls are now crumbling and Mark's attempts at renovating it have actually speeded up the decay, meaning many of the rooms are now too unstable to live in. Sarah and her team of specialists probe the walls and find large sections that are little more than dust.Also, the original slates on the roof have been replaced with much heavier concrete tiles, adding too much weight to the increasingly fragile home below. And to top it all, the cottage timbers are being eaten by woodworm.As Mark and Gudren face mounting bills, their planned wedding is delayed indefinitely and they're stung to realise that their seemingly bargain home is worth considerably less than they paid for it. Sarah and her team of specialists need to come up with an innovative solution to this extreme situation.