What strong water proof material can we support sliding window frame to?

[PatDIY_Dad]

This bit of steel is a box section for sub sills to go on for sliding windows
It has to be level and as you can see there's a bit of fall to the existing concrete which we will screed and tile over

The sub sills and box section can't be used to screw anything structural to because it'll just crumble

What can you put underneath so it's strong enough to screw the sub sills for the heavy sliding doors that would also be water proof
Then screed will be cemented in behind and in front of it

 

 

[MitchellMc]

Hi @PatDIY_Dad,

Returning to my comment on your previous discussion, I don't see many other options other than creating a raised foundation out of structural grout. Provided it is constructed correctly, and Ankascrews are used instead of Dynabolts, there shouldn't be any issue with crumbling.

Let me tag @Noyade, @TedBear,@Dave-1 and @Nailbag for their thoughts.

Please let me know if you have any questions.

Mitchell

[PatDIY_Dad]

Cant just use like galvanised steel on some of the sections and those plastic shims you can buy that come in 20mm / 10mm / 5 mm etc to make up any left over room as we pack them in

Thanks for your reply

[MitchellMc]

If the instructions don't call for the box section to be entirely supported along its length, then that sounds like it might work, @PatDIY_Dad. We have these galvanised square washers that might be useful.

Mitchell

[TedBear]

Hi @PatDIY_Dad 

I've just had some heavy sliding doors installed (Double glazed) this week. The installers used plastic wedges glued together (abt 1 metre apart) to get the frame straight, then filled the gaps with what looks like blue expanding foam ... but it set supportively firm and with limited expansion, so I don't think that is what it actually is.

Unfortunately they were very tidy and took all their discards away, so I can't say what the product was. Maybe a Bunnings employee (MitchellMc?) will know. I would think that the structural grout suggested by @MitchellMc could be good choice.

[PatDIY_Dad]

I spoke to the installer and he will fix them to the existing concrete (would need longer screws or Dyno bolts)

And use those plastic packers for the height

I asked if they are strong enough and he said yes but all they'll be fixed to the concrete 

[EricL]

Hi @PatDIY_Dad 

Please keep us updated with your progress, we look forward to seeing the track frame properly supported.

If you need further assistance, please let us know.

Eric

[Dave-1]

Good Evening @PatDIY_Dad 

Sorry I didnt see this yesterday, Does the supplier have any recomendations? I just went to Dr google and had a look and suppliers of the sills seem to have sets of requirements.

While I was trolling through the different specs I was thinking if you just used screed would it be strong enough (then realised what you meant by "it would just crumble" lol ) So back to yours and @MitchellMcs suggestion of the Galvanised washes mixed with the plastic spacers to support the channel Seems to be a good way to go. 

I was also wondering what are you going to do with the drain? and the water that will want to flow/seep up against the outside of the channel and screed?

Dave

[PatDIY_Dad]

Yeh water already flows to the drain on its own but because it's going to be screeded and tiles I'll get the tiler to make it fall to the drain with the screed and tiles they'll take out the drain and lift it