Create a slope on floor

[nish75]

Hi

I am about to put engineering floor in my landing. My landing has been extended a few years ago and as a result the floor is partly timber and a small part concrete (see picture). There is a small slope on the timber flooring but the concrete flooring is level. Since I’m planning to lay the engineering wood vertically, it would bend and may break. My plan was to create the same slope on the concreted floor as it is on the timber floor. I got someone to do this – he took the concrete floor out and put a new semi dry screed floor on, but the stupid guy made it level again despite my instructions. My question is

“How can I create a slope on the concrete floor without breaking it up all again. I need to raise it by about 2 cm by the door starting from the end of the timber floor.”

Would be grateful for any thoughts/ideas.

Cheers

Nish

 

[Doggit]

I can't remember what they are called, but your local woodyard should be able to make you a couple of "wedges" to give you the required fall. Place these either side of the hallway, and glue them lightly in place, and then get a piece of wood slightly less than the width of the hallway to use as a tamp, and then make up a mix of sharp sand and cement 3:1. Pva the existing concrete floor with a mix of 3:1 water and pva to slow the suction, and as it start to go tacky, put down the cement mix, and use the piece of wood to give you your slope. You'll also need a trowel to help you then smooth and level the floor. After it's gone dry, knock out the wedges, and then fill in the side pieces.

 

[nish75]

Many thanks Doggit. I like your idea of using a wedge. I have three following-up quesions if you don't mind. 1.
1. Do I need to add water to the mix of cement and sand?
2. Can I use any cement or are there some special cement that will work best?
3. Do I use PVA or SBR?

Thanks

 

[Doggit]

You want a dryish mixture (hardly and water) so that it holds it's shape. Too wet, and it'll try and settle, so it will be worth experimenting to try and get a mixture that holds up at the top of the slope. Any cement is fine, as is PVA. On reflection, you could go with a third wedge in the middle of the floor, and that'd stop you putting a dip in the slope as you run the trowel over it to flatten it; something like this, or longer if you can find it.

 

[nish75]

Thanks for the tips and I like the trowel. Just wondering if the semi dry screed will hold when it becomes thin towards the timber floor.

 

[Doggit]

It should glue itself to the existing concrete, but yes, it's a potential risk.

 

[nish75]

Probably make it wet at the end?

 

[JohnD]

Called Firrings, or Firring pieces.

Also used to put a slight slope on a flat roof.

The ones I have seen are the width of the joists or roof timbers, and taper to nothing at one end.

 

[nish75]

Cheers, it seems that they do sell it too, like here. Hopefully I can find the right slope.

 

[nish75]

Revamping this thread. The maximum thickness of the screed will be 20mm and the minimum 2mm.
An suggestion as to what is the best way to mix the concrete?
Semi dry may not hold well with 2mm.

Thanks

 

[Tigercubrider]

Wouldn't you do better to do the bulk in concrete but then top it off in floor leveller ?
You'd get a fine finish on the thick concrete and leveller will deal with very thin gaps?

 

[nish75]

Very good idea. Do you mean semi dry screed for the concrete bit?
Also can you make self levelling compound less runny such that you mould it a bit?

 

[Tigercubrider]

I don't know

My extension is a bit higher than my kitchen, discovered when removing the old back door.
I made it good with concrete , then several years later a fitter covered the entire floor with latex/leveller when fitting flooring

Presumably a strong mix goes off quicker than a self levelling compound