Slab Design

[GrantMcscott]

Hi

I have my slab make up back and from reading the forums it does not match what other people are doing.  I plan to use 100mm Celotex ga4000  underneath the sub-floor for the insulation as per the drawing.  On top of the slab I plan to put more insulation on top of the sub floor about 50 mm, then lay the underfloor heating with a screed of about 60 mm

 

Does this sound correct as a lot of the reading I have done on the forum suggest the slab then the insulation.

 

thanks

 

 

[ragg987]

We have (bottom to top)

 

EPS 300mm

Concrete slab 150mm

Insulation 50mm

Membrane

Screed 50mm

Finish floor (engineered timber)

 

This is to achieve PH levels and eliminate cold-bridging. Looks like you have much less insulation and will also get cold bridging at the wall junction?

[Triassic]

I have a simpler design

 

300mm EPS (designed by Hilliard Tanner and a DIY install by me).

100mm of concrete (up to 250mm thick in the ring beams) with underfloor heating pipes zip tied to the top layer of reinforcing mesh.

Power floated finish to the concrete. Our pump guy is local and this was included in the pump hire.

 

 

Edited May 2, 2019 by Triassic

[GrantMcscott]

What would be the best way to get rid of the thermal bridge?

[Triassic]

36 minutes ago, GrantMcscott said:

What would be the best way to get rid of the thermal bridge?

In one of the original designs Proton blocks were suggested.

 

This web site shows a number of different designs of passive slabs and how to eliminate the cold bridge, http://www.viking-house.ie/passive-house-foundations.html

 

edit to add “use the above web link with caution, just look at the pictures” - see Jeremy’s post below.

 

Edited May 2, 2019 by Triassic
Use with caution

[Conor]

18 minutes ago, Triassic said:

I have a simpler design

 

300mm EPS (designed by Hilliard Tanner and a DIY install by me).

100mm of concrete (up to 250mm thick in the ring beams) with underfloor heating pipes zip tied to the top layer of reinforcing mesh.

Power floated finish to the concrete. Our pump guy is local and this was included in the pump hire.

 

 

Exactly what I intend to do. Seems simple and effective. Did you have your DPM under the insulation or above? And did you use EPS100 for everything or denser for the ring beam and load bearing walls?

[Jeremy Harris]

16 minutes ago, Triassic said:

In one of the original designs Proton blocks were suggested.

 

This web site shows a number of different designs of passive slab, http://www.viking-house.ie/passive-house-foundations.html

 

 

Be aware that the linked website is STILL using copyright material of mine, despite numerous requests I've made to get the rogue that runs it to take it down.  Thankfully some of the images he's been using without my consent have been taken down, but there is a section drawing of our house which I drew up for our building control submission that is still there (no idea where he got it from, it's an edited version of a drawing that's in my blog, though).  The website linked to had nothing to do with the construction of our house,despite claims made in the past that they actually built it!

 

Edited to add:

 

I was wrong, the rogue is still using all the photos of our build on his website!  If anyone is tempted, then ask yourself whether you'd trust someone that uses someone else's build to advertise their own services, when they had nothing to do with it.

[Triassic]

20 minutes ago, Conor said:

Exactly what I intend to do. Seems simple and effective. Did you have your DPM under the insulation or above? And did you use EPS100 for everything or denser for the ring beam and load bearing walls?

I’m on limestone so I have a radon barrier located above the first layer of insulation, this is a dual radon and DPM barrier.  

 

The load bearing areas are a mix of EPS 300, 200 and 150, depending on the load and were designed by a structural engineer.

 

 

 

Edited May 2, 2019 by Triassic
Typo

[jack]

13 minutes ago, JSHarris said:

I was wrong, the rogue is still using all the photos of our build on his website!  If anyone is tempted, then ask yourself whether you'd trust someone that uses someone else's build to advertise their own services, when they had nothing to do with it.

 

Must be worth a DMCA complaint to the host company by now?

[Jeremy Harris]

6 minutes ago, jack said:

 

Must be worth a DMCA complaint to the host company by now?

 

I tried this, but they demanded a $50,000 deposit from me before they would even look at whether there was any breach of copyright.  The owner of the company that's abusing my copyright (and, in my view, fraudulently presenting our build as if it was his work, when it wasn't) refuses to remove the images, and has been refusing to acknowledge my take-down requests.

 

As the domain is registered in Ireland, the only way to proceed seemed to be to go through the European courts last time I checked.  As I've now got dual nationality, I might try and see if I can get the Irish authorities to take action.  Last time I got wound up about this I was still just a UK national.

[Simplysimon]

3 hours ago, GrantMcscott said:

What would be the best way to get rid of the thermal bridge?

marmox , 65mm thick which is a brick thickness. use instead of one course http://www.marmox.co.uk/products/thermoblock brickie thought they were easy to use. as others have said, you need more insulation under slab.