This Blog focuses on the traditional indirect water storage system, where only the kitchen sink has a mains connection and the rest of the cold-water draw-offs are supplied from a large tank.
The only time we tend to consider these tanks is when:
- They leak, causing damage to the interior.
- An overflow pipe is gushing the contents of the tank to the exterior and possibly soaking the external walls, leading to damp penetration to the interior.
- We fall ill through brushing our teeth or washing our faces with contaminated water.
In older water storage systems these tanks may be of galvanised steel or asbestos: the former is likely to be badly corroded and will eventually leak; the asbestos tank poses no danger in water, but the outside face should be checked to ensure that it is not breaking up or 'dusting.'
Modern storage systems have plastic tanks but all types of tank must meet the following requirements:
- Be properly supported on a plywood base, with timber bearers beneath.
- All sides and the top of the tank should be fully insulated to prevent freezing.
- All pipes to and from the tank should be insulated.
- The tank should have a tight-fitting lid to stop any debris getting into the water-this also prevents access for vermin and birds which may gain temporary ingress into the loft.
- Fitted with an overflow pipe (separate from the one utilised by central heating header-tank).
Unlike a mortgage valuation, a House or Flat Purchase Survey and Building Surveys by Woodward Chartered Surveyors includes advice on water tanks (if present) as standard.