Basement Tanking - anyone had one done?

[Maggiethecat]

My basement has been damp for years but really bad now.

Has anyone had theirs tanked, how was it and was it expensive?

@Maggiethecat ‘My basement has been damp for years but really bad now.’
hopefully not a euphemism.

What are you using the basement for? Is it brickwork or has been previously tanked? What is the floor?
Tanking is just the application of a waterproof render to the walls, and some sort of waterproof flooring. Most of the tanking I’ve seen fails after some period of time. However the methods of tanking now with mesh integrated into the fender seem much more sturdy.

It’s beneath our flat, used for storage only. Exposed brick and concrete floor and don’t think it was tanked previously when the conversion was done (Victorian house).

The damp smell permeates the flat, likely through the floorboards.

Not sure if we would ever use down there for anything other than storage although good to keep the option open. But at the moment you risk damaging things stored there.

I had my basement tanked about 15 years ago.

It meant fitting a plastic membrane to the floor and walls, then fixing wooden batons to the membrane to allow a cavity for air to circulate, then foil backed plasterboard and skim over that.

Similar to this: https://www.tracebasementsystems.co.uk/post/what-does-basement-waterproofing-cost

No rendering involved.

@Mildura - is your basement for living in?

I think the tanking I've seen involves applying several coats of cement based waterproofing slurry.

@Maggiethecat what ventilation have got going on?

I think there may be ventilation bricks.

It should be drafty down there. Ventilation is key. Check you have enough bricks and the holes are all clear.

We had the rear rooms of a commercial property tanked several years ago. It was partially built into a hillside so all the wet seeped in from the "uphill" side. We had the mesh as explained above, then plasterboard not quite to the floor, so there was a very tiny channel for drainage. We had to instal moisture-sensing fans which were on constantly, but it really worked.

My Auntie has stairs running from her ground floor flat into open (there's no door or curtain) tanked basement (I think which has been done in last 5-7 years). It doesn't smell at all, but paint in flaking which makes me wonder what's going on beneath the walls - there are six large airbreaks together at a higher level. Doesn't really help your concerns, but that's her situation.