Is tanking a basement a good idea?

[HouseNumpty]

Looking at a couple of houses both ~1880, 2 storey terraces with basements.
In one the basement looks untouched and has one obviously damp wall (the 'party wall' not the external one). The rest seems dry and there's no visual evidence of damp in the ground floor walls. There's quite a large window but no other ventilation.
The other has been tanked (10 years ago) and has painted walls, laminate floor, a wall-mounted radiator and a fire escape window. Again, no visual evidence of damp in the walls.
I've viewed/seen listed several of this type of house in the area and only 2 of them have had tanked basements.
Is that sort of tanking (effectively making a room) a good idea, or does it just hide damp behind it?
The house is currently unoccupied so no furniture to mask problems, and you'd think issues would have manifested after 10 years, but it makes me feel uneasy not knowing what the walls are doing!

 

[Deluks]

Yes, tanking does hide damp behind it. It seals the room and keeps the water away. The nature of basements, being below ground level means they are always going to be damp, think of what happens to rainwater.

Ultimately, if you want any basement room to be usable, you'll probably have to tank it.
Even just storing things down there could be problematic if you don't use airtight containers.

 

[HouseNumpty]

Where does the water go if it's tanked though? Tanking might keep the basement dry but not the walls above so you'd still get rising damp?

I'm interested in keeping the rest of the house safe rather than having a useable room in the basement.

 

[freddiemercurystwin]

Tanking is very effective if done properly albeit not cheap, water travels downwards so not really an issue, a few threads on here about tanking, generally there are physical barrier types of tanking which requires a masonry wall to be built in front of them or there are drained systems where any water is drained off, then there are the render systems which are very risky and and the least expensive but no way of knowing if they'll be effective or not, maybe have a search of the forum. If you don't know how the basement was tanked then probably give it a wide birth.

 

[freddiemercurystwin]

Basement tanking/ cellar damp proofing

Hi, I want to install a damp proof membrane in my cellar and was wondering if anyone can give me some advice on what type of membrane to go for. I have very limited knowledge of this topic but from what I know you get special plugs which are used to secure the membrane to the wall. Another...

www.diynot.com

 

[HouseNumpty]

'water travels downwards so not really an issue' - but damp rises? I don't see how/if tanking and damp in the ground floor of the house are connected.

The current owner did the tanking so I guess I could find out, if they still have any details/remember.

 

[Deluks]

The question you really need to be asking is does the house have a proper DPC. That's what will stop 'rising damp'

 

[HouseNumpty]

Thanks, that's clarified things!