How to waterproof external wall?

[BradC1]

Hi all,  I'm wanting to build an external stud wall with external sheeting/ cladding at one end of our patio. What is the best way to waterproof between the base stud and the concrete slab? Also would I need to put a membrane between the stud wall and the external cladding? TIA

 

 

 

[JacobZ]

Hi @BradC1,

Thank you for your question and welcome to the Bunnings Workshop community, it is fantastic to have you with us.

While you've indicated that you are not planning to fully enclose the patio, and it is unlikely you will need building approval, it is still worth making a quick phone call to your local council to confirm they are happy for you to proceed. A quick phone call can save a lot of pain in the long run if it turns out you are in breach of council regulations.

To build a good, waterproof wall, a few steps need to be taken. The first is ensuring you use the correct materials for the job.

You should use H3 Framing which is treated for exposure to weathering and can be used outdoors without a sealer or paint for your frame. Even though it will be fully enclosed, if water is to get inside the wall, it will be much more resistant to rot.

You should then attach plascourse to the underside of your bottom plate to prevent water transfer between the concrete and bottom plate. This can be attached with Liquid Nails before the stud wall is put together and shifted into place.

Once the frame is in place, it should be attached to the concrete using Ramset 10 x 100mm Galvanised DynaBolts in every second stud bay. The frame should then be sealed wherever it touches the concrete, posts and ceiling with Sikaflex 11FC.

A house wrap, such as this Ametalin 1370mm x 30m VapourTech Brane VHP Vapour Permeable Wall Insulation should then be attached to the outside of the frame following the manufacturer's instructions for installation.

Once these steps have been taken, you are 90% of the way to having a good weatherproof wall. Depending on the type of cladding, there are likely a few extra steps required, however this will be laid out in the manufacturer's installation guide.

Allow me to tag @Dave-1 and @Nailbag to see if they have anything to add or can see anything I might have missed.

Let me know what you think and if you have any further questions, please don't hesitate to ask.
 

Jacob
 

[Dave-1]

Morning @BradC1 

Going through @JacobZ steps for sure sure is a good way of builing the wall. The only bit I did not know was the plascourse I knew something should be used but not what it was.

Just thinking now as I write this I would suggest a "return" somewhere along it or a fixed point up top (but then it wont be free standing) to give it ridgility to the wind or party goers leaning against it. I can see why it may be a good idea to hit up your local council.

Dave

[Nailbag]

Hi @JacobZ 

I don't think I can add to much to what @JacobZ has already outlined as he's ticked of each point in addressing the external wall. Your only area left would be the overlapping roofline over the house roof tiles. I would suggest looking into a full length custom bent colourbond flashing sealed along the top of the alfresco roof down to the guttering. Its a tricky one to work out, but it just needs to be on the covered area of the gutter so the house roof water run-off isn't hindered.

Nailbag