Solum bitumen Liquid Tar

[riboid]

I am pretty confident on what my solution is for my basement problem, but it would be prudent to push it out there for some clarification:

 

Basement roof has been sprayed with Icynene open cell insulation (increased air tightness and likely exaggerated my issue) and since we had the roof and downstairs floorboards exposed, it got obviously wet.

 

Now, the liquid tar which was originally poured in the solum has, in large areas, gone and we have soil exposed, which is damp. My humidity readings are 90+, so reaching saturation levels and we have had severe mould growth (like a white fungicidal alien).

I have installed forced ventilation, but, I know that the volume of the basement is way too big to cope for the fans to do anything and mould growth continues in the perfect environment for its growth. 

 

To make matters worse, we had a chest freezer in the hall, just beside basement hatch, which was pissing water for heaven knows how long. That water has ran down (always finds a way) and run into the basement and also under my flooring (brand new £55 per m2) which has caused mushrooms to grow in our hallway (cleaned off and pointed my dehumidifier at it). Post basement works, ill lift up the flooring and rectify and moisture that is lying on top of the insulation and vapour barrier that is below the wooden floor (I think the vapour barrier has enabled the freezer water to sit there and struggle to dry out as the engineered wood is sitting on top of it. 

 

Below is my plan:

 

1. Suited and booted with my hepa 3 staged filtered vacuum, I will hoover up all signs of mould and fungus (yes, ill double bag the waste bag of the vacuum, wash down (bleach and appropriate chemicals) vacuum, wash filters etc - I worked in the asbestos removal industry, so well versed on protective measures).

 

2. The basement floor is immaculately clean, but I'll dust it out again and level of the ground as much as I can in readiness for the pour.

 

3. I'm gonna install 1000 swg heavy duty polythene on the floor, running it up the dwarf walls and basement columns about 100mm to 150mm, which will act as my vapour barrier.

 

4. I'm going to then install expanding foam tape around that polythene perimeter prior to concrete pour.

 

5. I'm going  to then pump in concrete and level it all over my basement, ensuring that when it meets with the foundation wall/solum junctions, it touches the expanding foam.

 

6. Ill leave concrete to set for a few months, then I'll get a dehumidifier down there (every good home should have one) and dry that sucker out to see of my humidity levels have been resolved.

 

7. Pending humidity levels, I will then staple and tape a vapour barrier over the sprayed icynene filled joists to prevent moisture ingress into the insulation itself. Ill dust walls down, prime and then spray tack and then tescon vana tape vapour barrier to the wall.

 

8. Ill then look at my ground floor mushroom in the hall issue,  by lifting the engineered wood up, do a clean up, dry off, clean down removing any fungal spires with bleach and solution and then dry out with dehumidifier. 

 

9. Cross my fingers.

 

[Suffolk peasant]

Was there sufficient ventilation in the basement once you removed the de-humidifier to stop recurrence?