Solid oak floor over BITUMEN residue concrete floor

[Ballie]

I know this has been discussed before but new products are always coming onto the market and I am sure someone will have found a solution to my project.

I am going to be fitting a solid oak tongue and grove floor; the planks are 160mm wide, 20mm thick and vary in length from 400mm – 2600mm.

The property is a 1960 built bungalow that had thin floor tiles glued down with what looks like Bitumen glue. The tiles were removed in 1999 at which point the floors had a coat of PVA (3 – 1 with water) what’s left on the floor is a very, very thin (as thin as a sheet of paper or thinner) coat of black stuff which I assume is Bitumen glue residue.

I have done a standard damp test by duck taping down a bit of 12” square polythene DPM and leaving it for 24 hours with the carpet back over it, when I removed it there was NO water droplets at all, so I assume there is no damp.

The Bitumen residue is very solid with no flaking and is very thin you can see it was put on with a very fine notched trowel (I would say about a 3mm spacing between notches) the glue left on the floor therefore looks like this, it has a 2mm wide (max) strip of glue and then a 3mm wide strip of the concrete floor showing, this is in wavy patterns all over the floor.

I have tried to remove the Bitumen in a 12” square area I have tried with a belt sander and a wire brush on an angle grinder and a paint scraper but it too solid and thin to get off with the scraper and all that happens with the power tools is as soon as it get hot it just smears over the floor. Therefore removal doesn’t seem an option.

I have been told by the Lecol rep that if the Bitumen is very thin and solid with some concrete showing through (as I have described) that I could apply 2 or 3 coats of “Lecol PU 280” which will act as a sealer/membrane and then use “Lecol MS 250 plus” to glue the floor down.

Please can anyone tell me has anyone used this method? is this likely to work?

Or has anyone found any other sealer/glues that will/have worked over this Bitumen residue

Or what other options do I have?

My thoughts are in this inventive world we now live there must be some products that will enable me to overcome my problems.

Thank you to anyone that can help. [GALLERY=media, 7775][/GALLERY]

 

[i_am_fubar]

I know this post is dead. But it really sums up my problem better than I have...

The Lecol stuff looks promising. Anyone ever used it?

Cheers,
Fubar.

 

[SUFCDAN]

I don’t know about the lecol? Any good

 

[dazlight]

It would of needed diamond grinding off back to the concrete then a epoxy liquid dpm

 

[SUFCDAN]

It would of needed diamond grinding off back to the concrete then a epoxy liquid dpm

Hi I see one of your old posts(2016) and you said UZIN PE 404. Over bitumen residue.

I have a similar, a residue of bitumen, and it needs a little self levelling. What’s your product and method choice please for solid wood over concrete, with the above. Thank you.

 

[dazlight]

Not for solid wood mate I wouldn’t do 404

I’d get this question on the theflooringforum.com as more floorlayers there but I’d be going

grind off old adhesive
Ardex DPM1c
Prime
3mm smoothing compound ardex K39

 

[dazlight]

Sheffield or Southend ?

 

[SUFCDAN]

Southend I’m afraid, The blades have done so well, in comparison to big premiership clubs.

 

[dazlight]

Nice one I’m a Tranmere fan and was in a box at your place earlier in the year. My in-laws areSouthend fans. Great weekend but rubbish match 0-0

 

[SUFCDAN]

Nice one I’m a Tranmere fan and was in a box at your place earlier in the year. My in-laws areSouthend fans. Great weekend but rubbish match 0-0

I miss football, I just want to see something on live TV, will be strange without a crowd though. (John Aldridge....what a player)


Thank you, I know this an old thread, the picture the guy posted above, (have a look please) my floor is exactly ( it cold be it!!) the same. I need to grind it back, so will have to hire a floor grinder (tried by hand with grinder , it’s not great). They do 10” floor grinders for hire near me https://www.mark1hire.co.uk/category/tool-hire/floor-preparation/floor-grinders/. I was looking at dfg200 or the 280 on the page, says it needs 32 amp 110, does that normally mean I supply my own transformer? Do they normally come with grinding heads? As I see there are different colour diamond heads for stuff, what colour for the above residue picture?

Thank you

 

[dazlight]

Get this on the flooring forum.com mate.
But you need a ripper disc. You can get them for hand grinders as well

 

[SUFCDAN]

Get this on the flooring forum.com mate.
But you need a ripper disc. You can get them for hand grinders as well

I had a look on the floor forum, could not find anything under sub floor prep for “ripper” do you have links for something for a hand held? Thanks

 

[Deleted member 174758]

..... says it needs 32 amp 110, does that normally mean I supply my own transformer?

It's maybe worth understanding that on trade sites (the main target market for hire firms) 110 volt is mandatory and in many cases the main contractor is responsible for its' supply and upkeep, so there is often a hard wired transformer available. As a user you still need to know the size of plug/cable (110 volt tools in the main comes on 16A or 32A plugs). On jobs where there is no 110 volt power supplied you often have to hire a transformer and extension cables, too, unless you own your own. A 32A tool will normally require a transformer of 5kVa to 6.5kVa rating with at least one 32A outlet (some units come with multiple 16A outlets, but no 32A outlet). So basically you need to hire a transformer as well

Watch out where you plug in. These transformers can trip breakers on circuits which are already heavlly loaded!

 

[Deleted member 174758]

Now this bitumen stuff i hear is nasty and can't be laid on. So i am working out how to remove it/and get back to concrete/ a work around. from my internet searches, asking mates and asking my dad i have the following options
1. some solvent e.g. kerosene which does dissolve it ( tried a small area with meths) which allows it to be scraped. not keen as a total waste of solvent and a lot of hardwork.. messy but maybe neccesary?

I'd be wary about lifting bitumen. Sometimes it really is the floor's DPM, so lifting it can affect any floor you subsequently lay on top of it; sometimes that "bitumen" is actually Marley flooring adhesive, which generally contains small amounts of chrysotile (asbestos) fibres, so caution (e.g masks, damping down with water, etc) is advisable. The thought of using solvents such as kerosene in an enclosed space is worrying to say the least - kerosene vapour mixed with air is potentially explosive (after all, it is used in jet engines as the propellant) and might be set off by a spark from something seemingly as innocuous as a light switch, but it's your choice

As to the Lecol, as a joiner I have repaired parquet block flooring where I had to install over an existing thick bitumen bed and it worked well on that (I recently revisited one site where I did such a repair in 2017 and it's still OK), but that stuff isn't a sealant - it's an adhesive with a filler and is designed for parquet repair. It's also not cheap

3. My dad suggests getting a scrabbler to bash it up.. This is the really serious way and currently the favourite proposition which could work great but can't find anybody online thats suggested/ done it? maybe its too damaging?

The most common type of "scabbler" you'll come across from hire places is the pneumatic needle scaler - and in "scabblers" one of the best known names has to be Trelawny. You say the bitumen is soft, so it will probably just clog the needles of a needle scaler and you'll need to stop regularly to clean them up with a solvent. You'll also need a fairly chunky compressor - around the 10 to 15 cfm mark. You can get heavier "scabblers" which are designed to remove heavy rust and for ship defouling which use much larger "needles", but they might well damage concrete. I've used the needle scalers on sandstone and they work well, albeit relatively slowly.

If you must lift it, will a flooring bully (flooring scraper) with a thin blade and a lot of sweat equity not do it?