Solid wood floor on Concrete

[mattysupra]

dont worry. This stuff is childs play with the correct advice. First things first is moister test. Must be below 75% rh! Get the result and come back to me/us for the next instructions

 

[BigTim]

Right. Carpet lifted and old parquet blocks levered up. They were on tar paper sheets and stuck to the concrete with bitumen. floor is mostly still covered in bitumen.

Concrete looks and feels dry as a bone which is good, but seriously undulating which is not. I think a skirting board will have to be reoved or cut and then, moisture test permitting, a screed applied... Q is whether to go whole hog of priming, sealing, screeding, priming again as it's the hall we cannot live in the house without walking through.

With the depth of fill, I think it'll have to be water based screed, hope to give it a day or 2 to dry out before flooring (say screed tomorrow, floor on weds). Still hoping to stick down with an appropriate adhesive..

RE: moisture test, don;t think my mate has a moisture meter, where can I get one?

 

[BigTim]

Looks like a big variation in height across the floor

Got a flooring guy coming to tomorrow to properly screed it. Then will have to leave it a few days before we self level and I guess we've just guaranteed it'll be too damp to stick the wood down so it'll have to be combi underlay and float it. Sigh.

 

[WoodYouLike]

Even so Big Tim, before installing the floor floating you have to make sure the new screed is as dry as possible otherwise the moist will be kept underneath the combi-underlayment and cause rotting and/or problems later.

Moist has to go first, sorry. Better to be a bit more patience than having to start all over again.

 

[BigTim]

Even so Big Tim, before installing the floor floating you have to make sure the new screed is as dry as possible otherwise the moist will be kept underneath the combi-underlayment and cause rotting and/or problems later.

Moist has to go first, sorry. Better to be a bit more patience than having to start all over again.

Was thinking of screed tomorrow, self level Friday and then flooring on Monday.. Area is 6m2 and will prob stick the heating on to help it along. Sound along the right lines?

Glad you're online W-U-L because the nxt Q is about finishes. Research on here and your site leads me to hardwax oil (osmo) as the best solution for me as I want a oiled appearance to match other rooms but some dirt and moiture resistance.

The oak is untreated and needs to colour match as best possible the oak in the other rooms. So, can I get coloured osmo polyx oil or can/should I stain first?

The Easyoil product at floors2go interested me at first but if it's just a conventional oil then I suppose it will look tired and dirty very quick in the hall?

Thanks for your advice.

 

[WoodYouLike]

Was thinking of screed tomorrow, self level Friday and then flooring on Monday.. Area is 6m2 and will prob stick the heating on to help it along. Sound along the right lines?

Open some windows when the heating is on full: that way the excess moist goes out of your house sooner. Please remember - and I will say this again and again Bit Tim, sorry - every inch of new concrete screed needs 30 days to dry sufficiently - no two ways about it.

New Oak treated with natural HardWaxOil will turn darker (you can always try this out with any wood type to see what colour it will become once finished with a natural finish, by wetting a little piece of the wood with water) and over time will turn that typical honey oak colour.
If your floors in the other rooms have a stain you can use a colour HardWaxOil, but be adviced that there always be a colour difference in the beginning.

Hope this helps

 

[mattysupra]

also dont try putting levelling compound down until screed is dry. Like woody said 1" a month in ideal conditions. And with the weather like it is now, you can add extra time on. Also dont try and force dry the floor. It will make it weak, Shrink more and crack.

 

[BigTim]

also dont try putting levelling compound down until screed is dry. Like woody said 1" a month in ideal conditions. And with the weather like it is now, you can add extra time on. Also dont try and force dry the floor. It will make it weak, Shrink more and crack.

Gah. So now I'm going from doing the job in 2 days (orig estimate ) to 1 week (yesterday's estimate) to over a month ?

This is the entrance hall that contains the stairs, we can't live in the house without walking through it. Screeding guy said dry enough to walk on in 12 hours and compound in 3 days. What's the alternative? Using some other levelling compound/screed instead of concrete to the required depth?

Previous monkeys obviously concreted and then bitumen within days and stuck the old floor on top with tar paper DPM- no obvious sign of moisture damage and it had been down circa 20 years (was very uneven mind).

Way I see it whatever we do we've got to get this floor level before anything else can be done re flooring.

 

[WoodYouLike]

You can walk on it Just not install wooden flooring on it (yet)

 

[mattysupra]

What is the depth your trying to cover? And not sure about the 3 days on the compound? do you mean 3 hours?

 

[BigTim]

What is the depth your trying to cover? And not sure about the 3 days on the compound? do you mean 3 hours?

I think my mate with the spirit level said the variation 15mm (I hope the sais 15 not 50 ) across the floor from one side to the other in one part. There's a dip in another part of the floor of a similar depth. Basically he figured it was too much to fill ("would take bags and bags") with just compound and needed a concrete screed before self levelling.

Screeding guy said we could put the self level compound on top of the screed in 3 days time, plan was to leave that over the weekend (so another 72 hours) before flooring.

But, we're saying, I should wait another 30 days so that the combi underlay won't get wet on both sides and wreck the flooring (currently taking up a good part of the adjacent dining room) ?

 

[mattysupra]

Something not right here. You cant put screed down at 15mm. To thin. The minimum thickness on a bonded method is 30mm. Not to sure if your mates know what there doing! If they did say 50mm, thats more like it. But this will raise the floor height alot unless digging out old floor. But then you need a concrete base installed to. unless there taken off a top screed. Guess you dont have a top screed! Also you should never apply levelling compound to a wet base thats trying to dry. ( It will come up when you lay floor on top) You can just put levelling compound down and fill it with correct aggregate to save on bags. Then you need second nice smooth skim on top of that (minimun 3mm) You also need to find out about moister in floor to find out what compound and prep work to carry out. Thing is that wood will not forgive any mistakes made in the prep work. It will fail!

 

[BigTim]

Something not right here.. Not to sure if your mates know what there doing! Thing is that wood will not forgive any mistakes made in the prep work. It will fail!

It's all good news on this thread

Will check again in the morning, looking at the floor i can believe 50mm as the floor noticeably dlpes from one side of the room to the other (not so noticebale when carpet and underlay were down). The previous bodgers thought it wise to scallop out the concrete in the doorways to meet the other floor levels instead of getting it all level

So, it's not possible to level on screed after 3 days - it will just break up? And we actually need to use a levelling compound and pack it out with aggregate to fill in the larger areas? I'm getting this right?

All above based on the moisture being low enough otherwise need to prime and surface DPM before levelling?

Be interesting relaying this info to the flooring bloke coming in the AM...

 

[mattysupra]

Yes thats about right. The screed will not bond to the correct shear strength if layed to soon, depending on what your using and if you use correct. Your floor does not need to be level. Just smooth! Also depending on what method of screed they are using, 50mm can also be to deep. Now for the tech bit
For fully bonded screed the surface of the concrete base should be scrabbled or shot blasted to remove contaminates, laitance and to expose the aggregate. The optimum thickness of the screed is between 25mm and 40mm. For thickness greater than 40mm there is an increased risk of the screed debonding from the base.
All screeds laid direct over dpm's (except for epoxy bonding dpm's ) must be considered as unbonded. The minimum thickness should be 50mm but, for certain kinds of floors, the screed may need to be thicker.
Simple stuff

 

[BigTim]

Yes thats about right. The screed will not bond to the correct shear strength if layed to soon, depending on what your using and if you use correct. Your floor does not need to be level. Just smooth! Also depending on what method of screed they are using, 50mm can also be to deep. Now for the tech bit
For fully bonded screed the surface of the concrete base should be scrabbled or shot blasted to remove contaminates, laitance and to expose the aggregate. The optimum thickness of the screed is between 25mm and 40mm. For thickness greater than 40mm there is an increased risk of the screed debonding from the base.
All screeds laid direct over dpm's (except for epoxy bonding dpm's ) must be considered as unbonded. The minimum thickness should be 50mm but, for certain kinds of floors, the screed may need to be thicker.
Simple stuff

It just gets better and better

As already mentioned, the floor is almost covered in bitumen, sounds like screed is not going to bond to that?

I'm just a simple IT consultant