Sbr mixing to tank basement

[Uncie]

Hi all,

bit new to this site but to jump in head first I'm trying to find a bit of information on sbr as a tanking agent

basically I've purchased a house with a basement and on first inspection it looked sound and dry, the house was built over 100 years ago.

I proceeded to put a scratch coat of 4 sand 1 cement with water proofer left for a time to get on with other jobs I have notice that the wall has damp spots randomly in the wall these being a foot square or smaller the are ranging from two foot of the ground to eight foot.

i gathered some information about the sbr from another site giving instructions on how to mix and apply but the main thing I'm worried about is, the wall being stone and having big gaps between, basically from what I have gathered the sbr won't stick if its more than 6-8mm thick.

If I could get some information on mixing and applying the sbr it would be great help

 

[Arti]

You would be better putting a tank slurry on top of ya render thats already on. better still get someone out to give you a damp survey before you go any further......................welcome to the forum.....................:RpS_thumbup:

 

[johniosaif]

I would take off all you put on, apply a splatter coat of one sand one cement with sbr in the water at 3/1 ,use sika I water proofer in second coat, mix ratio 2 sand one cement with the sika at 10/1 water to sika, use a splatter coat 3/1 sand cement with no additives, next day mix sand cement ratio 3,5 sand to 1 cement with sika in water 10/1 , all these coats need to be overlapped and scooped into the floor overlapping each other, keep dampened for a week, sbr at 3/1 and skim if its straight and flat enough otherwise use limelite on top to straighten, then skim

 

[Uncie]

Has anyone heard of anything like this :









One such tanking system would be to brush on a 1:1:1 (Sand: Cement :SBR) slurry, covering the whole wall. LEave 24 hrs.


Then coat with 1:1 (Cement :SBR) slurry, then onto this a 3:1 (sand: cement) render scratch coat (or better still the second coat keyed with a scud coat rather than scratched) mixed using 3 :1 (water:SBR).


Leave at least 24 hrs, then apply a floating coat of render, 4:1 with the same water:sbr ratio. You can either rub this up with a float and sponge it or skim it. I'd rather not skim it myself, if I could help it. The SBR can be Ronafix , Cementone, Isocrete whatever. Dont' use any beads . The wall can be lapped onto a floor and screeded over too if belwo ground level.


You could also use Sika products which are excellent. They have similar systems


For damp proofing, (ie rising damp, above ground level no water ingress from outside) as long as the wall is brushed down and dust free, a propriety dampproof additive in a 4:1 or 3:1 sand and cement render (see spec on additive) will be fine, and keep salts and damp at bay. You can skim it up, no worries and again dont'use beads in the float coat, but you can stick them on for skimming.


Cheers

 

[lucius]

Have a look at Mapeilastic

 

[windy]

So in the situation of rising damp the sbr goes in the scratch coat ? And if so you you still use a watered sbr or a scud coat before you apply the scratch coat???

 

[Olican]

Welcome uncie, I must have tanked 4 or 5 different ways over the years following builders specs. The prefered method is usually the cheapest by most builders. I always recommend to clients that they get a damp report (usually done free) and take it from there, a lot of spreads have different ideas on tanking