Has anyone done/have experience of using a membrane system to tank a cellar?

It seems not to be a complicated process, but I haven't seen any details
from someone who has done it themselves and appearances can be deceptive

As cellar converstion costs seem to run around the £40K mark, and I have
a £20K budget, I'm thinking I could save a heavy amount by having the
underpinning and floor lowering done by a contractor but doing the
tanking and finishing myself.

Is this a viable route?

Danny Monaghan wrote:
Has anyone done/have experience of using a membrane system to tank a cellar?

It seems not to be a complicated process, but I haven't seen any details
from someone who has done it themselves and appearances can be deceptive

As cellar converstion costs seem to run around the £40K mark, and I have
a £20K budget, I'm thinking I could save a heavy amount by having the
underpinning and floor lowering done by a contractor but doing the
tanking and finishing myself.

Is this a viable route?

Could you define what you mean by a 'membrane system'?

The probs with a bonded membrane is that a high water drive can disbond
the membrane from a weak substrate as is normally found in previously
damp brickwork. Once it is disbonded water builds up behind and
disaster results.

Look at cementitious waterproof coatings which will allow the substrate
to breathe. There are several on the market. I sell one but am not
going to advertise. Most can withstand about 20 metre head of water and
can be, and in fact must be, applied to a damp substrate. They are
applied by brush,roller or airless spray. They do not look very pretty
but can be overclad, (do not pierce the coating for batten fixings).

There are Epoxy/Bitumen coatings available but a) They do not breathe
and are OK for rearside applications (positive water pressure) and b)
Bitumen smell seems to last forever. Same rule applies regarding
fixings.

On 5 Jul 2006 08:59:32 -0700, a particular chimpanzee named "Bookworm"
randomly hit the keyboard and produced:

Danny Monaghan wrote:
Has anyone done/have experience of using a membrane system to tank a cellar?

Look at cementitious waterproof coatings which will allow the substrate
to breathe. There are several on the market. I sell one but am not
going to advertise.

Go on, say it. Vandex by any chance?
--
Hugo Nebula
"If no-one on the internet wants a piece of this,
just how far from the pack have you strayed?"

Hugo Nebula wrote:


Go on, say it. Vandex by any chance?
--
Hugo Nebula

Wrong. There are about 6-10 manufacturers out there. I sell for one
nobodys ever heard of and only sell to the trade. The poster would
never be able to buy the product I sell even if I named it.

Just trying to impart some of my experience of selling Tanking
Membranes and Tanking Coatings over the past 20 years.

Probably will be met with cyncism by some of the trolls who inhabit
this group.

Bookworm wrote:


Could you define what you mean by a 'membrane system'?

The probs with a bonded membrane is that a high water drive can disbond
the membrane from a weak substrate as is normally found in previously
damp brickwork. Once it is disbonded water builds up behind and
disaster results.

Look at cementitious waterproof coatings which will allow the substrate
to breathe. There are several on the market. I sell one but am not
going to advertise. Most can withstand about 20 metre head of water and
can be, and in fact must be, applied to a damp substrate. They are
applied by brush,roller or airless spray. They do not look very pretty
but can be overclad, (do not pierce the coating for batten fixings).

There are Epoxy/Bitumen coatings available but a) They do not breathe
and are OK for rearside applications (positive water pressure) and b)
Bitumen smell seems to last forever. Same rule applies regarding
fixings.


I was thinking about something like this from Newton Membranes:

http://www.newton-membranes.co.uk/System500.htm

Basically from what I've read, these systems that control water flow
rather than holding it back are better, and seem to be simple to install.

Danny Monaghan wrote:

I was thinking about something like this from Newton Membranes:

http://www.newton-membranes.co.uk/System500.htm

Basically from what I've read, these systems that control water flow
rather than holding it back are better, and seem to be simple to install.

I have looked at the Newton Website and they quote:

'Newton Titan Sump and Pump to remove excess water that may enter from
behind the sealed membrane system.'

I rest my case.

A 100% perfect way of tanking in such circumstances is what is called
'curtain injection' whereby holes are drilled at predetermined spacing
through the wall and over the whole walls surface, to the outside
substrate. An Acrylic Resin Gel is then injected at high pressure which
form a waterproof curtain between the subsoil and the outside of the
wall. Thus you are preventing the water from entering the walls in the
first place.

It is very expensive and needs special pumps and experinced operatives.
Being used worldwide to seal leaks in tunnels, CTRL, London
Underground, Tunnel between Denmark & Sweden, Dublin Port Tunnel etc
etc.

Owain wrote:

So no-one could object to your naming it, then.

Owain

And then be flamed for advertising! Do me a favour? Address the guys
problem or shut up. If you aint got nothing to say on the subject dont
bother posting.

Danny Monaghan wrote:
Bookworm wrote:


Could you define what you mean by a 'membrane system'?

The probs with a bonded membrane is that a high water drive can disbond
the membrane from a weak substrate as is normally found in previously
damp brickwork. Once it is disbonded water builds up behind and
disaster results.

Look at cementitious waterproof coatings which will allow the substrate
to breathe. There are several on the market. I sell one but am not
going to advertise. Most can withstand about 20 metre head of water and
can be, and in fact must be, applied to a damp substrate. They are
applied by brush,roller or airless spray. They do not look very pretty
but can be overclad, (do not pierce the coating for batten fixings).

There are Epoxy/Bitumen coatings available but a) They do not breathe
and are OK for rearside applications (positive water pressure) and b)
Bitumen smell seems to last forever. Same rule applies regarding
fixings.


I was thinking about something like this from Newton Membranes:

http://www.newton-membranes.co.uk/System500.htm

Basically from what I've read, these systems that control water flow
rather than holding it back are better, and seem to be simple to install.

I am in the process of installing something very similar to the Newton
system in my basement. I've used Wykamol since the sales guy was happy
to sell to me as a non-qualified installer. They also sent an
installation instructions CD which was pretty clear. By far the biggest
problem is managing awkward shapes/corners etc. When it came to doing
the floor I built a small cardboard model of the floor and cut strips
of card to represent lengths of membrane and used this to work out all
the overlaps, cut and fold lines etc. When laying it with my general
constractor (no previous experience of the stuff) we used the model as
a template. Only cut 1 bit wrong out of 60sqm.

I used it in a refurb where I was putting in a new floor and rather
than use their perimeter drainage I installed perforated land-drains
(with geotextile wrapped round to prevent clogging) running to a sump.
Buy the sump pump separately as it's much cheaper and use something
like a small cold water tank as the sump chamber.

In total cost of the membrane stuff came to £750 and it's a pretty big
cellar, and an extra ~£150 for the sump pump and associated gubbins.

My cellar has rubble stone walls so the other problem was making
successful fixings. As a result I hung it like curtains as less fixings
required and will put up a stud wall inside this. If you've got brick
walls it would go up like a dream and you can either use a version
suitable for plastering directly onto, or fix battens to your 'plugs'
and dry-line.

This is definitely a DIY job and suitable for almost all types of
building (mines a listed Georgian townhouse). If you want further
specific advice email is as presented.

Fash

Forgot to say I also did floor lowering but not by underpinning.
Underpinning not a sensible option (for me) as walls are 600mm thick
and rubble stone so liable to keep falling into any trench dug out for
underpinning. If you don't need much height gain (I've gone from 6'3"
to 6'8") then you can use a reinforced 'bathtub' floor where the
reinforcing forms an upstand at the edge of the room, which when
concreted forms a ring beam which holds back the earth at the base of
the foundations. The whole floor needs to be reinforced to prevent any
problems from heave lifting the middle of the floor.

I did all the digging out myself (with a little help from friends paid
with beer), put in the under floor drainage, and had a contractor put
in the sub-base and reinforced concrete, with a joint venture on the
membrane as I wasn't confident they'd give it the same attention to
detail that I would.

The other thing you need to consider is humidity as the membrane system
works best when not fully sealed at the ceiling so you still need to
deal with water vapour. I'm planning to put in a heat recovery
ventilator which can deliver 4 air changes/hr but with the same heat
loss as 1 change/hr. If this turns out not to be sufficient I'll add a
wall-mounted dehumidifier.

Total conversion cost including drainage, contractor, a new RSJ across
the room, stud walls, flooring (including undertile heating), lighting
etc. is estimated at £12-15k and gives me a room which is 19' x 13'.

If you want to share my ignorance further just ask.

Fash

On 6 Jul 2006 04:27:07 -0700, a particular chimpanzee named "Bookworm"
randomly hit the keyboard and produced:

And then be flamed for advertising! Do me a favour? Address the guys
problem or shut up. If you aint got nothing to say on the subject dont
bother posting.

Perhaps it's good that you don't deal direct with the public.
--
Hugo Nebula
"If no-one on the internet wants a piece of this,
just how far from the pack have you strayed?"

Bookworm wrote:
Owain wrote:

So no-one could object to your naming it, then.

Owain

And then be flamed for advertising! Do me a favour? Address the
guys problem or shut up. If you aint got nothing to say on the
subject dont bother posting.

You wouldn't be flamed by anyone worth worrying about.
Your expertise would be helpful to many readers, myself included.

Bookworm wrote:

'Newton Titan Sump and Pump to remove excess water that may enter from
behind the sealed membrane system.'

I rest my case.


Sorry, I don't get what you mean here.