Ditra mat, how good is it?

[tweakyboy]

Hi,

Just venturing over from the plumbing forums. I'm after some advice about Ditra mat, I went to a tiling shop today for some quotes on tiles and mentioned that I have 2 different floor types (wooden floor boards on old part of house and sand and cement screed on the new extension) and need to ply the floors before tiling it.

The guy on the counter mentioned about using Ditra mat. Just a few questions on it can I lay this over old floorboards without the need for any ply/hardibacker underneath? How good is Ditra mat does it beat the pants off just plying the floor? If it makes any odds I'm using 300x600 porcelain tiles.

I've added a couple of photos to show you what the floor is like currently.



Thanks in advance, Dan

 

[DHTiling]

You will need an expansion joint at the substrate break.

Cement boards on the timber floor and slc the screed to suit.

 

[tweakyboy]

Thanks for the reply Dave, I've been doing a bit of looking around ideally I would like to keep the floor height down to a minimum now that I know there is another option out there. Would it be possible for me to remove my old floor boards and fix around 25mm of ply down to match up with the new floor screed? This then removes the need for the hardibacker and SLC'ing the new screed, still plan on using the Ditra mat all the way through just saves me sometime!

I'm just thinking of other options other than raising floor level, I have to take floor boards up anyway to re-plumb.

Thanks for your advice

 

[DHTiling]

Yes that is fine, but you still need expansion joint where timber meets screed.

You can get them same colour as the grout, Dural uk do them to match Mapei grouts.

 

[tweakyboy]

Thanks for the fast responses. Just worked out that it works out cheaper to rip up the old floor boards and replace with 2 layers of ply, one 12mm and on 9mm as floor boards are bang on 21mm, rather than board the existing floor with hardibacker and then SLC the new screed. So all in all it works out best in both worlds, less of a build up of floor level and a cheaper option! Not very often you get that happen.

Do you recommend using Ditra mat on every installation as a belt and braces method, or only when its a problematic floor?

Thanks again

 

[Muse2k8]

As Dave said an expansion joint is a must otherwise you will just end up with problems when the two substrates expand and contract at differing rates. You will end up with cracks, tenting etc.

 

[DHTiling]

Use 22mm ply, not 2 layers. The single thickness has more structural strength.

The Ditra is belt and brace and worth it on certain installs.

 

[tweakyboy]

Thanks guys, where are you purchasing your 22mm ply from most places around here only stock the normal 12, 15, 18, 25mm boards. I plan to use 2 expansion joints as I have 2 openings into the new extension.

 

[DHTiling]

Just use 25mm then and feather into that from the screed side.. 3mm is easily overcome

 

[CptPugWash]

ditra mattings good,3mms not to bad to get over unless its 300x600 rectified porcelain laid brickbond :ninja: