Lead pipes

propertyhunter

Thanks everyone for your responses.
It is London, so a hard water area, but there is a water softener under the sink. 
I'll conduct lead tests on the water inside the house after we've bought it and take it from there. Fitting a filtration system seems like a decent compromise until the house is renovated. The interior needs to be taken back to the brick, as the electrics, plumbing/central heating need a substantial upgrade. The pipes actually run on the surface of the walls and through the ceilings - it's not been touched since the 1970s and has been in one family since then.

FreeBear

propertyhunter said:The interior needs to be taken back to the brick, as the electrics, plumbing/central heating need a substantial upgrade.

It is well worth putting insulation on the walls before plastering - Removing more than 25% of the plaster from the exterior walls in a room triggers Building Regulation compliance, which would require the addition of insulation. 60-75mm of Celotex/Kingspan will get you up to the minimum required level.

Once you have a decent level of insulation, combined with good quality double glazing, there is no real need to have radiators under the windows - This means you can site them on internal walls and minimise the amount of plumbing. Also worth oversizing the radiators and leave the option to install air/ground source heat pumps at some point in the future. Even if you don't go for A/GSHP now, you can run a gas boiler at a lower temperature and get a slightly better efficiency out of it.

propertyhunter

@FreeBear - thanks for the advice. I will make a note of your comment for future reference. What I do know about the walls is that they do have a cavity, so we can fill the cavity too. I think we will try to get a heat pump of some sort, seeing as that's the way things are moving - but will get expert advice.