‘Diary of a Waterproofing Designer’, is a an advert that we produced after attending three very similar problems of tanking failure in a short space of time.
Taken from the advert:
Diary of a Waterproofing Designer
My name is James Hockey, and I specialise in structural waterproofing design. Below are several examples of inspections I have undertaken within the last six weeks, all typical of the problems we advise on again and again and again and again… The thing is, such expensive problems need not ever happen in the first place.
Recently constructed house into a hillside, not yet completed and waterproofed with externally applied bitumen sheet membranes. Why has it failed? Poor waterproofing design. The land drains couldn’t be installed at the correct level, so encourage ground water to pressure on the tanking, and because membranes often have defects once installed, groundwater pressuring on such defects is a bad thing. The result? Approx. £10k spent on the original system, plus a further £10k for the remedial system.
Recently constructed house not yet completed (£1m build) with sizeable basement. Waterproofing design included land drains at the incorrect level, and so allow water to pressure on another bitumen membrane system. What looks good on a drawing is not necessarily practical to construct. Poor waterproofing design.
Twelve new houses constructed into a sloping site (all but two recently finished and occupied) with bitumen membranes applied externally, this time with insufficient land drainage included, again allowing water to pressure on the tanking systems, penetrating to varying degrees in the properties inspected. Poor waterproofing design.
The common theme here is that membrane tanking systems rely either on perfect workmanship, or sufficient land drainage, and often fail when water pressures because (a) drains can’t be installed as designed, (b) they are designed incorrectly, (c) they are not accessible for maintainance and clog in time. This commonly results in someone holding their head in their hands, wishing that Trace had been employed to totally take over the responsibility for the waterproofing design and installation. Contact us for information on how you can protect you and your clients.
For expert waterproofing design advice backed by professional indemnity cover, please contact us.